“The Benefits and Limitations of Static Headspace and Purge & Trap for the Analysis of VOC's”
Glynda A. Smith - Tekmar-Dohrmann

Static Headspace and Purge & Trap are two techniques that are used to introduce volatile organic compounds (VOC's) into a gas chromatograph. Both systems extract the VOC's from a sample matrix and then introduce the volatile analytes to the GC in a gas phase. While the two systems perform similar functions, the modes of extraction are drastically different. Selection of the appropriate method of sample introduction to the GC is critical to the success of a particular application. Static Headspace involves the equilibrium sampling of an aliquot of the VOC's from the sample matrix while Purge & Trap is a dynamic extraction of the VOC's from the matrix. Sensitivity in Static Headspace is proportional to an equilibrium constant at a particular temperature and, as a result, Static Headspace is typically a less sensitive introduction technique than Purge & Trap. The research performed will demonstrate the benefits of both techniques, thus drawing a clear distinction on where the two VOC introduction techniques diverge. All data will be evaluated for linearity, precision, and accuracy.

“Evaluation of a New Dual-System Purge and Trap Interface"
Glynda A. Smith - Tekmar-Dohrmann

Sample throughput is an increasing concern in analytical laboratories. Newer columns and gas chromatographs are available that offer great reductions in analysis times without sacrificing chromatographic resolution. Such capability puts pressure on GC sampling devices such as static headspace analyzers and purge & trap concentrators to also reduce cycle times. In this paper, a new approach is presented which involves the synchronization of sample preparation between two Tekmar purge and trap sample concentrators that are coupled with two Tekmar autosamplers. The system set up will be described along with the calibration and minimum detection limit data that was obtained.

“Evaluation of the High Dilution Capabilities of the SOLATek 72 Multi-Matrix Vial Autosampler”
Glynda A. Smith - Tekmar-Dohrmann

Today's analytical laboratories are faced with increasing demands for greater efficiency and productivity. Automated sampling systems yield the greatest flexibility for labs that require a high turnover in sample analyses. The SOLATek 72 vial autosampler fully automates the purge & trap analysis of water, wastewater, and soil samples in accordance with current USEPA methods for volatiles analysis. One of the unique features of the SOLATek 72 is the ability to program automatic dilutions as low as 1:250. As a result, high concentration samples can be diluted and analyzed with no manual intervention. In this paper, the full range of dilution capabilities of the SOLATek 72 will be explored. Data will be evaluated for linearity and precision.

“Total Nitrogen Analysis: A New Perspective on TOC”
Robert H. Clifford, Karnel R. Walker - Shimadzu Scientific Instruments

In the environmental field, carbon and nitrogen content are of great importance in various applications. Researchers can assess the effects on the overall carbon cycle by understanding on a micro level the effects of carbon and nitrogen concentrations on biological life forms in various matrices, including soils and seawater. More importantly, scientists are recently gaining insight into the ability of nitrogen to influence carbon concentrations, or "fertilize", in either fresh or saltwater, a process known as eutrophication. In years past, although many strides were made in measuring carbon levels with high sensitivity, total nitrogen measurement was not as sensitive as well as proved to be time consuming. However, using the combustion oxidation method in conjunction with chemiluminescence detection, an analyst can simultaneously measure carbon and total nitrogen levels with high accuracy and sensitivity in less than four minutes.

“Web-enabled Outsource Laboratory Productivity Tools”
Steve Gregory - Neolytica, Inc

Neolytica, Inc. enables companies to better leverage their capital, equipment and personnel by providing comprehensive, cost-effective, and on-demand analytical resources and services. Neolytica offers, via its powerful web-enabled tools and capabilities, a network of pre-qualified testing laboratories, state-of-the-art LIMS solutions, database management tools, and consulting services to assist companies with their analytical services needs. Their initial emphasis is on serving the needs of the petroleum, chemical, plastics and industrial gases markets. This paper will describe the considerations and issues that companies face when implementing an Analytical Services outsourcing strategy and the tools that are available through Neolytica to help realize the benefits of outsourcing.

“Burdick & Jackson Introduces NEW Inert II Solid Phase Extraction Columns for an Inert, Contamination Free Pathway for Sample Preparation”
Anthony Kemperman, Cynthia L Seaver, James T. Przybytek - Burdick and Jackson

A replacement for our current glass Inert SPE product line is being introduced in 2002. These new columns are manufactured of a specially treated polypropylene housing and our specially cleaned and manufactured stationary phases for the demanding applications in the environmental market. These columns will be a great way to save costs for your sample preparation needs, as they will cost approximately 30-50% less than their equivalent products in glass columns. They have also been tested and found to provide the same inert, contamination free pathway that the glass columns have provided. Our customers have tried them and love them.

“On-Line Determination of Total Sulfur in Gasoline and Diesel”
Rodney W. Spitler, Patrick J. Moore, Rodney L. Friudenberg - Thermo ONIX

Analytical methods that involve sample combustion followed by detection of SO2 are increasing in popularity. One of the more popular methods using this approach is ASTM D5453. Taking a method similar to ASTM D5453 from the laboratory to the on-line environment presents the following concerns: The method must be equipped with a series of predictive maintenance tools to minimize system downtime. To ensure a safe installation the method should utilize air instead of 100% oxygen as the combustion system oxidant. The on-line sample introduction system must fully account for all sulfur bearing compounds. An on-line method that fully addresses these concerns will be discussed.

“Automatic Reference Fuels Blending Apparatus for Octane and Cetane Number Determination According to ASTM D2699 , D2700 and D613 Standard Methods”
Denis Pons - GT instruments

The fully automatic NABLEND unit allows the preparation of reference fuels for the Octane and cetane number determination in accordance with the ASTM D 2699 , D2700 and D613 methods.This state of the art equipment with built-in touchscreen computer and printer allows the complete and automatic preparation of reference fluids from up to 6 different tanks with traceability print out reports and database .This simple to use tool increase the accuracy and speed preparation of reference blending fluid which are an essential factor to get accurate results in performing Octane or Cetane test in the Petroleum laboratories .In addition this unit allows full remote management and service over the internet or GSM/GPRS connection.

“Gas Chromatography Using Microwave Heated Columns”
John S. Crnko - Antek Instruments, L.P.

Conventional and Fast Gas Chromatography column temperature programming can now be readily accomplished by utilizing microwave energy. A Retrofit Kit, which installs in an existing GC, is described. This revolutionary technology uses specially treated low thermal mass columns to enable unprecedented column heating and cool-down capabilities. Common analysis, such as those used for mixed hydrocarbons, can use traditional temperature programming, and immediately yield a significant timesaving from reduced column cool-down rates alone. Aggressive Fast techniques can also be executed for applications such as simulated distillation. Economic advantages can be further enhanced when two microwave ovens are installed and operated simultaneously.

“A Novel Approach to Large Volume Liquid Injections in Gas Chromatography”
Dan DiFeo, Stuart Allan, Peter Dawes - SGE, Incorporated

For many years capillary gas chromatography has been the standard technique for the analysis of volatile and semi-volatile liquid samples. Its greatest limitation has always been the very small sample volumes that must be injected to avoid overloading the injection port or capillary column. There have been many accessories developed to combat this deficiency, such as Programmed Temperature Vaporizing (PTV) injectors, that can dispose of more than one hundred microliters of solvent prior to the sample being introduced to the capillary column. Such systems require a completely new injection port to be fitted to the instrument and rely on a large boiling point difference between the solvent and the analytes of interest. SGE has developed a novel way of injecting large volumes of liquid into a gas chromatograph without having to install a new injector or without overloading the existing one. Over one hundred microliters of solvent can be injected into a standard injection port, transferred to a capillary column, separated from the analytes of interest and disposed of. The result is a concentrated form of the sample that is deposited directly onto the capillary column. This new technology resulted from a breakthrough in multidimensional chromatography that allows a high-pressure high-flow pre-separation column to be used in conjunction with a low-pressure low-flow standard capillary column. The system is much easier to install than a standard multidimensional system and uses the standard injector hardware of the gas chromatograph.

“Benefits of a High Temperature Wax Phase”
Dan DiFeo, Angus Hibberd, Gerard Sharp - SGE, Incorporated

This paper describes the benefits of high temperature wax columns over conventional wax columns. The added thermal stability along with a high degree of inertness is the result of a unique bonding process. The polyethylene glycol phase is essentially embedded into a sol gel matrix. The sol gel is a synthetic glass, which is bonded to the fused silica. This gives the wax phase added thermal stability, inertness and robustness. Data will be presented that shows comparisons of bleed levels and applications of the high temperature wax columns compared with a standard wax column. The columns will be subjected to high temperature analyses of mixtures not normally analyzed on conventional wax columns due to their low maximum temperature. The increased thermal stability of the SolGel/Wax column gives greater flexibility to perform a wide range of analyses normally not able to be achieved on conventional wax phases. Along with an increased thermal stability, the unique bonding of the phase gives an increased inertness to a wide range of compounds such as alcohols, acids and amines. This inertness will be demonstrated with a series of chromatograms comparing high temperature and conventional wax columns.

“The Benefits and Disadvantages of Using Small Inner Diameter Capillary Columns”
Dan DiFeo, Angus Hibberd, Gerard Sharp - SGE, Incorporated

This paper describes the advantages and disadvantages of small bore capillary columns. It is well known that capillary columns of 0.10 and 0.15mm inner diameter can produce faster chromatography than conventional capillary column diameters of 0.25 and 0.32mm ID. These smaller diameter columns have been available for several years but have not been adopted by the general chromatography community. The columns are more difficult to use but with greater understanding, the benefits can be realized. Application data will be presented which shows the benefits and disadvantages of each of the diameters of 0.10, 0.15 and 0.25mm inner diameter. On the one hand, very small-bore capillary columns will yield faster chromatography but at a cost. The sources of the limitations are the sample introduction and detection parts of the chromatographic system. Lower flow rates of small bore columns will more easily show deficiencies in GC injector design, and smaller peak widths will test sampling rates in mass spectrometers. Nonetheless, the benefits of small-bore columns are waiting to be gained.

“A Comparison between Micro and Capillary HPLC Column Designs”
Dan DiFeo, James Mazaraki, Peter Dawes, Gerard Sharp - SGE, Incorporated

Micro and capillary HPLC have become more popular since several major instrument manufacturers introduced systems that easily accommodate the low flow and low dead volume requirements of these techniques. When coupled with MS and MS/MS detection micro and capillary HPLC becomes an extremely powerful analytical tool for the characterization of small samples. For this reason micro/capillary HPLC is especially useful for the analysis of proteins and peptides. Micro and capillary HPLC columns are readily available from several niche and mainstream manufacturers. The durability and robustness of these columns is inherently dependent on the column design. Researchers tend to prefer capillary tubing to use as column tubing, though many column manufacturers prefer the use of glass lined tubing for packing micro/capillary columns. This paper will compare the features of these two common micro/capillary column tubing materials with PEEKsil, a PEEK sheathed fused silica tubing. Data will be presented to illustrate the influence of the column materials on micro/capillary column design and performance. The fragility of fused silica makes it easy to remove voids by cutting the column down. Glass lined columns are extremely robust making them far more user friendly. PEEKsil is far more robust than fused silica and is available in bores of 50 microns or less.

"Improved Separation of Semi-Volatiles"
Dan DiFeo, Angus Hibberd, Gerard Sharp, Mark Ferry - SGE, Incorporated

Semi-volatile contaminants in water are some of the most targeted compounds for analysis in environmental laboratories today. This class of contaminants constitutes a wide range of compounds with differing physical properties and as such, is extremely difficult to analyze in a cost effective turnaround time. Low-bleed or mass-spectrum grade columns are required with the US environmental protection agency recommending that the analysis be carried out on a 5% phenyl column. This paper will show the use of a 5% phenyl column and a 100% polydimethylsiloxane column to give improved separation of 71 components of the US EPA 8270 mix in a reduced analysis time. The 100% methyl column used for this analysis is a sol gel derived column with high temperature properties. This is especially beneficial for the late eluting semi-volatiles, because the lower bleed levels leads to better signal-to-noise ratios and the higher temperature gives better peak shape and faster retention times. Both phases also show excellent inertness. Chromatograms will highlight some difficult-to-analyze compounds to demonstrate this. The high temperature limits of both of these columns is also handy for 'burning' any contaminants from the column after analysis of dirty samples. Thus, although the upper maximum recommended temperature of the method is 320°C, these columns can be used to temperatures in the 370-380°C range to remove column contamination. This ultimately can be incorporated in the GC method and results in less instrument downtime.

“Analysis of Pharmaceutical Solvents Using a New Low-bleed Capillary Column”
Dan DiFeo, Angus Hibberd, Gerard Sharp - SGE, Incorporated

Analysis of pharmaceutical solvents has become an important issue in the development of new drug design. Most of these solvents are low molecular weight, volatile compounds that can be difficult to remove from the final target drug. As such, analyses to determine the levels of these solvents are usually performed on specifically designed volatile columns. These columns are usually thick-filmed and have low thermal stability. The low thermal stability of these custom-designed volatile columns usually results in higher bleed levels in the later part of the chromatogram. Conversely, the high thermal stability and increased level of inertness of a high-temperature volatile column results in lower bleed levels at elevated temperatures while still retaining excellent partitioning properties for pharmaceutical solvents as well as drinking water, wastewater and groundwater volatile mixes. This paper will present data showing the analysis of pharmaceutical solvents using USP methods along with standard US EPA 502.2 and 624 mixes and difficult-to-separate alcohols. Bleed chromatogram comparisons of the high temperature volatile column with standard volatile columns will also be presented. The increased thermal stability of this new phase gives the flexibility of a wider variety of analyses to be performed at higher temperatures unable to be achieved on a standard volatile column. In addition, a more thermally stable phase will allow baking out of the column at higher temperatures, otherwise not possible with conventional phases. This allows for rapid analysis of volatile components in a semi-volatile matrix.

“Sample Focusing Techniques in Gas Chromatography”
Dan DiFeo, Stuart Allan, Peter Dawes - SGE, Incorporated

Peak focusing is the term used to describe the narrowing of the width of a peak. As a technique, it is extremely useful for improving the signal-to-noise ratio and increasing the detection limit of an analysis. There are many advantages of focusing a peak rather than injecting more sample when attempting to improve the method detection limit. In most cases, there is already enough sample on the column to achieve up to 1000 times better sensitivity, and injecting any more sample would almost certainly cause problems. Sample focusing uses the existing amount of sample that is on the column and decreases its bandwidth to make it more concentrated. This increases the peak height significantly, therefore improving the detection limit. There are many different ways to focus peaks in gas chromatography. This presentation will outline the pros and cons of each and how to execute them efficiently.

“AC 8612 Application Reports D 86 Physical Distillation Data for Naphtha and Gasoline Samples in 10 minutes”
Walter Spieksma, Han Spaans - AC Analytical Controls Inc.

AC Analytical Controls developed the AC 8612 application to check the specifications of naphtha and gasolines samples. The 8612 system uses a fast capillary method to determine D 86 boiling range for naphtha and gasoline samples in 10 minutes. The 24/7 operation and high safety standard of the 8612 application allow lab managers to substitute the traditional ASTM D 86 technique.

“AC 8634 Application Reports D 86 Physical Distillation Data for Jet Fuel and Diesel Samples in 4 - 8 minutes”
Han Spaans, Piet Collé - AC Analytical Controls Inc.

AC Analytical Controls developed the AC 8634 application to check the specifications of jet fuel and diesel samples. The 8634 system incorporates a fast SIMDIS method to determine D 86 boiling range for jet fuel and diesel samples in 4 - 8 minutes. The 24/7 operation and high safety standard of the 8634 application allow lab managers to substitute the traditional ASTM D 86 technique.

“Optimization of ASTM D 5186 and D 6550”
Don Crider - AC Analytical Controls Inc.

Two supercritical fluid methods are gaining acceptance for replacement of FIA (ASTM 1319). ASTM 5186, aromatics in diesel, has been required testing in California for several years. ASTM 6550, olefins in gasoline, has been required testing since January 2002. There are parameters to ensure the data stays good, and preventative maintenance procedures that help eliminate unexpected downtime. Typical parameters such as column quality and valve timing are important but flow and pressure of the supercritical fluid are different for this technique. Other supercritical methods for petroleum have shown real promise. These generally are for heavier samples where there are few current methods.

“Reporting True Boiling Point Data in Liquid Volume % Using Simulated Distillation”
Jim Maynard, Don Crider - AC Analytical Controls Inc.

Crude Oil distillation is controlled by volume measurements however analysis of crude oil is more accurate when measured by mass percent such as by simulated distillation. This is a more accurate technique than physical distillation. Conversion from mass percent to volume percent is difficult because the density of the crude varies with aromatic content and carbon number distribution. Most crude tower modeling programs use volume percent consequently simulated distillation data cannot be used even though the data is better. A new correlation for converting simulated distillation data to volume will be discussed.

“AC Reformulyzer Method Replaces FIA”
Gertjan Schaatsbergen, Han Spaans - AC Analytical Controls Inc.

AC Analytical Controls pioneered the Reformulyzer application, which incorporates test methods ASTM D 6293, DIN 51448-2 and PrEN 14517. In a single analysis, the AC Reformulyzer application completely identifies the gasoline specifications: benzene, total aromatics, total olefins and total oxygen. FIA (ASTM D 1319) determines total aromatics and total olefins. An extensive European inter-laboratory study demonstrated that the Reformulyzer has an aromatics and olefins precision that is two times better than FIA!

“A New Approach to Closed Vessel Microwave Dissolutions of Small Samples”
Leslie Rhodes - CEM Corporation

Closed vessel microwave digestion techniques, now widely accepted and commonly used continue improve and expand to meet the requirements of specialized applications. One of the latest innovations allows rapid microwave preparation of small samples (,50mg) with the convenience of in-vessel temperature measurement and high throughput. In certain situations only a limited amount of sample is available for analysis. This is particularly common with biological and agricultural tissues. Because the total sample size is so small, it is difficult to transfer with minimal dilution from a traditional microwave digestion vessel without losing analyte. It is also necessary to use less acid than is typically required in a larger vessel. A novel approach to handling this application is discussed in this paper. MicroVesselsT which have a total volume of 3mL or 7mL will be used to digest various sample types that typically require this capability. Temperature and pressure sensors are used to provide feed back control of the reaction conditions. This digestion technique allows the user to digest 26 micro-samples simultaneously with minimal acid volumes and without the loss of analyte during the transfer step. In addition to outlining this new technique, data and graphs including temperature and pressure conditions will be presented.

“Microwave Digestion of Large Samples: Open and Closed Vessel”
David Barclay - CEM Corporation

Microwave dissolution techniques and pressure vessel design have undergone significant advances over the last five years. However, technology associated with the handling of excess pressure evolved during the dissolution process has, until now, fallen into one of two, broadly based mechanisms; pressure is either completely contained during the entire digestion process with a safety membrane mechanism in place to quickly vent pressure should the pressure rise above the operating limits or pressure is relieved automatically in the same circumstance by a vent and reseal cover mechanism. This paper will outline a major development in vessel technology which incorporates both mechanisms into a single vessel. Analytical data will be presented demonstrating that the use of this combination type relief mechanism can more than double the amount of sample that can be run for traditionally problematic organic samples such as, oils, paper pulp, plant materials and foods which evolve large amounts of excess gas and hence pressure during the dissolution. Elemental recovery data will be presented for both volatile and non-volatile elements along with a comparison of pressure and temperature achieved for a variety of organic samples at different sample.

“Automated Acid Reflux Cleaning Method for Teflon, Glass, and Quartz Accessories Used in Trace Analysis”
James Pearce - Milestone Inc.

Analytical chemists take numerous precautions to ensure the lowest possible analytical blank. These precautions include the use of high-purity acids and reagents for sample preparation, powder-free gloves, lint-free protective clothing, rigorous cleaning of all sample preparation and instrument components, etc. Despite all of these precautions, many chemists still have problems controlling the analytical blank. Their problems usually results from the way the sample preparation and instrument components (i.e Teflon bottles, volumetric flasks, glass and quartz ICP/ICP-MS spray chambers and torches, sample and solution containers, microwave vessels, etc) are cleaned and stored. Milestone has developed the TraceCLEAN system to address these problems.

“Advanced Clean Chemistry Techniques for Controlling the Analytical Blank in Trace Analysis”
James Pearce - Milestone Inc.

This paper will discuss: 1) Clean chemistry techniques and how microwave sample preparation reduces the blank contribution from all four sources, 2) A new method for sample preparation component cleaning and controlling carry over and cross contamination, 3) Methods for purifying and determining regent purity.

“Measurement of Fixed Gases in Commercial Helium using a Dielectric Barrier Discharge Helium Ionization Detector.”
Matthew Monagle - Advanced Industrial Chemistry Corporation (AIC)

Gas chromatography is an excellent tool for the analysis of impurities in high purity gases. The key to using GC effectively is a detector that is easy to operate and maintain and yet has the sensitivity to detect contamination at less than a part per million level. AIC Corporation has developed a dielectric barrier discharge based helium ionization detector for the analysis of fixed gases using that meets these requirements. Analysis were performed on commercial helium from various vendors using this detector. These results and the principles of operating the dielectric barrier discharge helium ionization detector will be presented.

“Recent Developments in Determination of Heavy and Crude Oil Stability and Compatibility”
Juha Vilhunen, Mark Knight - Finnish Measurement Systems Ltd/Med-Lab Limited

This paper reports on the developments, technology and applications of an automatic heavy/residual fuel oil analyzer (trade name Porla). Automatic analyzers are powerful tools compared to the still widely used manual methods. The precision of this automatic analyzer is three times better than that of the manual method and enables the running of visbreaking and hydrocracking processes of oil refineries to be set closer to the severity limits and thereby improves significantly the profitability of these processes. In addition, the third application of this automatic stability analyzer, the determination of the compatibility parameters of crude oils and their variable mixtures, enables correct mixing to prevent shut downs of oil refining processes due to incompatibility problems. Furthermore, the crude oil compatibility application may help refineries to select feed stock more economically. The performance and benefits of the automatic analyzer will be illustrated by real life

“Low Level Bromine Index Measurement”
Tore Fossum - Mettler Toledo

As petroleum products become more pure, there is more interest in low level bromine index determination. Two techniques are described here for instrumental analysis of electrometric and coulometric bromine index determination for products with bromine index of below 10. The basis for these analyses are ASTM methods D2710 and D1492.

“Titration Training Seminar”
Tore Fossum - Mettler Toledo

Sharpen your titration skills with a training seminar from Mettler Toledo. In this one day seminar we will present titration theory, electrode theory and maintenance, the modern titrator, developing effective methods on Mettler Toledo DL5X and DL7X titrators, optimizing titration parameters, automation, and data acquisition. Compliance with CFR 21 part 11 dealing with electronic records will be discussed.

“Adjudication of Reported Nitrogen Interference with Respect to Total Sulfur Determination by Oxidative Combustion and Electrochemical Detection”
Herb A. Hernandez, Karl-Heinz Jahr - AJ APS Technologies, Inc.

It has been reported that unspecified, but large, amounts of chemically-bound nitrogen in hydrocarbon liquids can interfere with the determination of total sulfur content by the oxidative combustion / electrochemical detection method (OCECD). This report will define the history and function of the OCECD technique, investigate possible and probable causes of the reported interference, site practical and analytical investigation of the basic analytical method, and propose viable conclusions and solutions. Also, since the reported interference was observed with liquid hydrocarbon materials, this report will confine its investigation specifically to these matrices.

“Sample Capacity Study on the Improved Restek Rt-QPLOTT Column for Petroleum Applications”
Barry L. Burger, Jarl Snider - Restek Corporation

The Restek, bonded Rt-QPLOTT column is a high-sample-capacity, porous polymer fused silica column used in the petrochemical industry for the analysis of C1-C10 light hydrocarbons, gaseous and volatile hydrocarbons, and solvents. The Rt-QPLOTT provides high sensitivity, fast analysis, and high resolution. It also features a large sample capacity to handle the wide concentration distributions present in petrochemical samples. The Rt-QPLOTT column is completely bonded and requires no particle trap. This study investigates sample capacity and its affects on peak symmetry.

“A New Low-Bleed, Thermally Stable PDMS Liquid Phase for Packed Column Simulated Distillation Analysis According to ASTM Methods D-2887-01 and D-3710”
Barry Burger - Restek Corporation

Restek's polymer synthesis chemists have perfected a new PDMS (polydimethylsiloxane) polymer-the new Rtx®-1HT column-for use with packed column simulated distillation. The thermal characteristics of this polymer are far superior to any other PDMS liquid phase currently available. With a maximum temperature of 430°C, this new polymer far exceeds the performance requirements for ASTM Method D 2887-01 for petroleum products and fractions, and for ASTM Method D 3710. We will demonstrate the stability of this column for C16-C18 resolution, retention time, and bleed.

“MXT 1HT performance study- ASTM D-6352-98”
Barry L. Burger, Dinesh Patwardan - Restek Corporation

ASTM Method D-6352-98-the analyses of petroleum distillate fractions with an initial boiling point >174°C and a final boiling point of <700°C-requires a rugged analytical column with a fully cross-linked 100% PDMS polymer that has high thermal stability. Using the new Restek MXT®-1HT simulated distillation column, a study was conducted plotting the critical method criteria: C50-C52 resolution, retention time stability, column bleed, and longevity.

“Improved Analysis For Simulated Distillation, Detailed Hydrocarbon Analysis, And PIANO Analysis Using A New Gas Chromatograph And New Petrochemical Software”
Michael Marrale, Jr., Charles R Lyle, and Ronald D Snelling - Shimadzu Scientific

Technology advances in gas chromatography have improved the analysis of many types of GC analytical methods. This poster focuses on the improvement to the analysis of simulated distillation, detailed hydrocarbon analysis, and single column PIANO. A new gas chromatograph and chromatography software has dramatically improved the quality, speed, and accuracy of these petrochemical methods.

“Instrument Interfaces for the Petroleum Industry”
Mike DeWitte, Steve Bolton - Labtronics Inc.

An instrument to LIMS interface must assemble data from a wide variety of sources and present it to the LIMS in a legible and meaningful format. Ideally it should also provide for monitoring and review of data before the data is committed to the LIMS and give users at every level access to the information that they need, when they need it. This presentation will discuss how to implement an instrument to LIMS interface that addresses the particular needs and requirements of the petroleum industry.

“Determination of Alkanolamines Using Cation Exchange Chromatography and Non-Suppressed Conductivity Detection”
Robert Steves, Brian M. De Borba - Metrohm-Peak, Inc.

Amines encompass broad industrial applications in various industries, such as the environmental, pharmaceutical, and petrochemical. Alkanolamines, in particular, are used for the removal of acidic components, as corrosion inhibitors, or in petroleum demulsifiers. Their high hydrophilic nature allows them to be easily eluted from a cation exchange column using either a simple dilute mineral acid or a weakly acidic complexing agent. However, since these amines elute under similar conditions as common inorganic cations, the addition of a modifier is sometimes necessary to allow for an optimum resolution between other analytes of close proximity. This paper discusses the use of cation exchange chromatography for the separation of alkanolamines and the influence of selectivity upon the addition of a macrocylcic ligand used as a modifier.

“An Optimized Method for the Determination of Trace Perchlorate in Environmental Samples”
Brian M. De Borba, Robert Steves - Metrohm-Peak, Inc.

Perchlorate has been found as a contaminant in ground and surface waterways in several U.S. states. However, sources appear to be confined to localized regions generally associated with military and aerospace activities. As a result of its potential impact on the thyroid gland, the U.S. EPA's Office of Ground Water and Drinking Water placed this anion on the Candidate Contaminant List for drinking water in 1998. Currently, the U.S. EPA recommends an action level between 4 to 18 ug/L, although some states have adopted their own levels. In this paper, we discuss an optimized method based on ion chromatography for the determination of trace perchlorate in environmental samples. The method allows for quantitation of perchlorate in the linear range of 0.5 to 50 ug/L using a large sample loop, a hydroxide eluent modified with p-cyanophenol, and suppressed conductivity detection. This paper will focus on the method detection limit (MDL), precision, and the recovery of perchlorate in fortified environmental samples.

“Orthogonality: The Key to Resolving Thousands of Peaks in Petroleum Samples”
Chris A. Billesbach, Joel R. Termaat, and Edward B. Ledford, Jr. - Zoex Corporation

GC x GC (Comprehensive Two Dimensional Gas Chromatography) is an emerging technology for complex mixture analysis. It routinely separates thousands of peaks from petroleum samples, and sorts them into recognizeable peak patterns that are easy to interpret. The power of GC x GC derives from a fundamental idea: the ?orthogonality? of the two capillary columns used in GC x GC analysis. This term refers to the fact that independent mechanisms of separation are available in the first and second columns of the GC x GC instrument, so that these separations can be though of as ?perpendicular? to one another, even though the columns are physically in series. The ?perpendicularity? of the separations yields a multiplicative gain in peak capacity: the peak capacity of the system is the arithmetic product of the peak capacities of the columns. This is what accounts for the enormous separation power of GC x GC. This presentation addresses a common misconception about orthogonality, namely, that it results from the differences in stationary phases between the first and second columns. This is not so. Orthogonality results from the temperature program. Understanding this non-intuitive aspect of GC x GC is essential not only for understanding GC x GC theory, but for practical issues, such as tuning GC x GC instruments to maximize separation power.

“Using GC x GC to Separate Aliphatics from Aromatics in Sim-Dist Separations”
Joel R. Termaat, Chris A. Billesbach, and Edward B. Ledford, Jr. - Zoex Corporation

A new type of GC x GC system permits Sim-Dist with first-dimension column and run-time conditions identical to those commonly used in 1-D Sim-Dist separations. With GC x GC Sim Dist, aromatics fractions can be physically separated from non-aromatics fractions with no prior fractionation. This leads to facile determination of both compound classes in Sim Dist analysis. This presentation examines the advances in hardware and software that have led to GC x GC based Sim Dist.

“GC x GC: A New Horizon in Petroleum Analysis”
Edward B. Ledford, Jr.1* and Steven E. Reichenbach - Zoex Corporation

GC x GC (Comprehensive Two-Dimensional Gas Chromatography) is a powerful new tool for petroleum analysis. The subject of much research over the last 12 years, GC x GC hardware has now matured to the point that it is robust, reliable, and easy to use. GC x GC software, while still in prototype phase, is developing rapidly. With the advent of mature software for processing GC x GC images, GC x GC will become a routine technique in gas chromatography. This seminar covers the basic theory of GC x GC, explains in detail how GC x GC hardware is installed and operated (demonstrations will be made during the seminar), and provides participants with a detailed introduction to the software with which GC x GC images are processed. Specific applications of GC x GC to problems in petroleum analysis will provide practical understanding this extraordinary separation technique.

“Determination of Petroleum Oils using Fourier-Transform Infrared Spectroscopy”
Timothy Alt, Shannon Richard, Dr. Kimberly Abramo, Dr. John Monti - Shimadzu Scientific Instruments, Inc.

Waterborne oils resulting from leaks, spills, and buildup are a major concern to the petroleum manufacturing industry and pose an environmental risk. Identification of petroleum oils has long been a tedious process often leading to indeterminate results. The unknown sample is identified qualitatively by comparing the FTIR spectra peak to peak changes and their ratios to known samples. This method is very susceptible to sampling techniques, oil mixtures, and degradation effects over a short period of time. New advances in FTIR will be applied to waterborne petroleum oil analyses, reducing sample preparation and utilizing spectral manipulations. A comparison between these results and current methodology will be discussed.

“Low Level Sulfur in Fuel Measurements”
Dr. Michael C. Pohl, Mr. David Malone - Horiba Instruments

New regulations controlling sulfur levels in various fuels will be implemented in the coming years. These considerably lower levels have required the development of new techniques and new instruments. These new technologies have come under intense scrutiny over the last several years. Studies on low level samples have been run both in Europe and the United States. These studies will be discussed in detail and the capabilities of the various methods assessed. The effect of potential interferents such as nitrogen in the fuel will be investigated. The strengths and weaknesses of the various methodologies will be described. Challenges for analysts investigating fuel purity will be discussed.

“Graphical Software for GCxGC Image Processing and Analysis”
Stephen E. Reichenbach [1], Mingtian Ni [1], Visweswara Kottapalli [1], Arvind Visvanathan [1], and Edward B. Ledford, Jr. [2] Company: [1] University of Nebraska-Lincoln; [2] Zoex Corp.

This new software system provides a graphical user interface (GUI) for automated and interactive processing and analyis of images produced by comprehensive two-dimensional gas chromatography (GCxGC). GCxGC provides a multiplicative increase in separation capacity over traditional gas chromatography and generates data in significantly larger quantity and richer complexity. The quantity and complexity of GCxGC data makes human analyses of GCxGC images difficult and time-consuming and motivates the need for automated processing. The graphical software supports many important operations including file I/O, data visualization, automated baseline correction, automated peak detection and manual peak editing, peak pattern recognition, and report generation.

“Automated Quantitation with GCxGC Data”
Stephen E. Reichenbach [1], Mingtian Ni [1], and Edward B. Ledford, Jr. [2] [1] University of Nebraska-Lincoln; [2] Zoex Corp.

Automated quantitation of images produced by two-dimensional gas chromatography (GCxGC) is important because GCxGC reveals an order of magnitude more peaks than traditional gas chromatography. Several steps are required for automated quantitation. Baseline correction is required to account for the non-zero offset which varies slowly across GCxGC data. Segmentation or blob detection is required to separate the samples (or pixels) that are associated with each chemical peak from the background samples and other peaks. Quantitation is required to measure the responses in each blob peak. Reports for GCxGC data may contain thousands of distinct peaks.

“A New Gas Chromatograph System for Improved Sensitivity and Throughput”
Ronald D. Snelling, Michael Marrale, Jr., and Charles R. Lyle - Shimadzu Scientific Instruments, Inc.

A new gas chromatograph system has been designed for high throughput and standard applications. Advanced features of this system include the latest generation of electronic flow control for all gases, including high-pressure capability to allow the use of microbore columns. Detectors are designed for high precision and sensitivity, and to allow fast GC analysis. An advanced software package with wizards allows all features to be accessed easily. The linearity and precision of this system will be demonstrated. Examples of applications from the environmental, pharmaceutical, and petrochemical industries will be presented. High speed GC applications will also be presented.

“A Novel Gas Chromatograph - Mass Spectrometer System for Improved Sensitivity and Throughput”
Ronald D. Snelling, Michael Marrale, Jr., and Charles R. Lyle - Shimadzu Scientific Instruments, Inc.

A novel gas chromatograph - mass spectrometer system (GC-MS) has been designed to increase the sensitivity of routine analysis. The system also includes feature to improve sample throughput, including the latest generation of high-pressure electronic flow control to allow the use of microbore columns. The system also features differential pumping of the vacuum chamber to provide ideal conditions throughout the chamber, and to allow the use of higher column flow rates. Examples will be shown for the new system in a variety of applications, including typical analyses in the environmental, forensic, and drug testing fields. Applications for both volatile and semi-volatile analytes will be shown. Examples of sensitivity and precision will be shown.

“Improved Sensitivity of Environmental Analysis using a New Gas Chromatograph System”
Ronald D. Snelling, Michael Marrale, Jr., and Charles R. Lyle - Shimadzu Scientific Instruments, Inc.

A new high performance gas chromatograph has been developed to improve the speed and quality of analysis. The system features the latest generation of electronic flow control, including high-pressure capability to allow the use of microbore columns and atmospheric pressure compensation to improve retention time reproducibility. Detectors have also been designed to increase the sensitivity and precision of the analysis. Examples of various environmental analyses are shown to demonstrate the precision and linearity of the system. Results will be shown for organophosphorus and organonitrogen pesticide and herbicide determinations. In addition, result of determinations of organochlorine pesticides and polychlorinated biphenyls will be presented.

“Anti-Corrosive Properties of a Uniquely Deposited Surface for Metal Substrates in Petrochemical Service”
David A. Smith, Gary A. Barone - Restek Corporation

Within the petrochemical industry, there are a variety of metal surfaces exposed to corrosive environments. As tubing, fittings, connectors, manifolds and flanges deteriorate, costly periodic maintenance, replacement, or substitution with expensive specialty alloys is required. It would be of considerable benefit if standard materials (e.g. stainless steel) could be treated with a thin protective layer to extend or eliminate the required service/replacement period of a system. We propose a uniquely deposited surface that is chemically bonded to a substrate, is highly inert, and will coat all exposed areas during the application process. An evaluation of its anti-corrosive properties will be presented using ASTM and NACE standards.

“The Preparation of Low Concentration Hydrogen Sulfide Standards”
Robert Benesch, Tracey Jacksier - Air Liquide

Experiments have been made to determine the factors affecting the stability of hydrogen sulfide calibration mixtures at concentrations below 1 ppm. Quantitative data was obtained which illustrates that material selection and surface treatment are major factors affecting the shelf life of low concentration reactive gas mixtures. With proper material selection and surface treatment, H2S standard mixtures on the order of 100ppb can be maintained for no less than 9 months. This presentation will illustrate and describe issues related to surface interactions and adsorption. Included in the discussion are: (a) The effects of various materials on stability of hydrogen sulfide, (b) Effects of passivation as a means of deactivating the material and (c) Long-term stability data.

“Triple Detector GPC for Particle Size Determination”
Brad Wurm, Kristel Gutierrez, and Bill Seekatz - The Dow Chemical Company

Applications of triple detector gel permeation chromatography (GPC) for particle size determination will be presented. Particle Size is determined using the Einstein Equivalent sphere radius formula. The formula uses the weight average molecular weight (Mw) from the light scattering detector and intrinsic viscosity of the sample from the differential viscometer to arrive at a value for the swollen particle size. The advantages of using this method will be presented.

“Total Sulfur and Speciated Halogen, including Fluorine, Determinations by utilizing a Novel Automated Combustion Prep Station with Ion Chromatography”
Mark Manahan, Ralph Brooks, Dave Thomas - Cosa Instruments, Houston, TX; Kirk

Total halide and sulfur determinations in various refinery feedstocks, intermediates and products by ion chromatography will be presented. We will describe a technique to perform on-line sample decomposition using a novel automated combustion prep station. The advantages the user gains by using IC for this analysis are: · Sub mg/L determinations are possible · Simultaneous sulfur and chlorine can be performed on one instrument rather than two, easier operation, less time spent changing cell configurations and equilibrating. · Ion Chromatographic separations eliminate halide interferences from bromide and iodide. Various real samples will be presented to demonstrate the advantages of this technique.

“Improving processes: Can High Temperature Combustion replace Kjeldahl Nitrogen?”
Mike Purcell - Tekmar-Dohrmann

Total Kjeldahl Nitrogen (TKN) is the standard for wastewater organic nitrogen analysis. This environmentally unfriendly, time-consuming test is often dreaded by the labs that are required to perform it. Technology using High Temperature Combustion (HTC) and chemiluminescence detection to measure total bound nitrogen (TNb) offers a faster, easier, and safer alternative. Already employed in Europe (per methods EN-12260 and DIN-EN-ISO 11905-2), this technique could represent a significant advance for labs in the United States.

“Ion Chromatographic Determination of Anions and Cations in Petroleum Products”
Kirk Chassaniol, Matthew Neely - Dionex Corporation

The determination of ions in organic materials ranging from solvents to sludge has been aided by improvements in column and detector technology used in Ion Chromatography. These scale and corrosion producing salts are present either as their free species in moisture or organically bound and released under increased heat and pressure conditions. This presentation will survey the sample preparation steps necessary for these measurements. From simple "dilute & inject" techniques to various extraction methods for "free" ionic contamination as well as total organic halide and sulfur content conventional combustion followed by IC will be presented. We will describe a new conventional combustion followed by IC will be presented.

“The Development Of An Application That Incorporates Mass Spectra(MS)Data Into Detailed Hydrocarbon(DHA)Analysis Data”.
Roberto I Meneghini, Joaquin Lubkowitz - Separation Systems, Inc

An application has been developed to unite Mass Spectra Data acquired an delivers all its properties into a detailed hydrocarbon analysis software. The main advantage of this system is that the DHA data software can incorporate the MS Data into one single program thus avoiding the cumbersome work of transferring MS identities and properties to a Chromatographic Data Program.

“Solving Industrial Problems Using Comprehensive Two-Dimensional GC”
Bill Winniford, Kefu Sun, James Griffith, Matthias Pursch, Jim Luong and Hernan Cortes - The Dow Chemical Company

Impurities in process streams at low ppb ~ low ppm levels can severely affect processes, particularly catalytic processes. Generally it is difficult to identify sub-ppm components with regular GC. Comprehensive two-dimensional GC (GC X GC) greatly enhances GC resolution and signal detectability for trace impurities. A picture of impurities chemical structural distribution can be visualized by boiling point and polarity. A longitudinally modulated cryogenic system (LMCS) was used as a modulator for GC X GC. It can be operated up to 350 deg C for analysis of high boiling impurities. Strategies for component identification will be discussed.

“Ion Chromatography Users Meeting”
Kirk Chassaniol - Dionex

Gulf Coast Conference attendees with an interest in Ion Chromatography are invited to attend a user’s discussion group. This session be comprised of presentations by vendors, practitioners and provide a room full of experts to assist in your IC methods. Topics for discussion prior to meeting are welcome by sending an e-mail to: gcc@gulfcoastconference.com

“Visualization of Polymer Fragments' Structural Distribution Using Pyrolysis Comprehensive Two-Dimensional GC (Py-GC X GC)”
Kefu Sun, Bill Winniford, Shayne Green, Bruce Gerhart and Brad Wurm - The Dow Chemical Company

Pyrolysis GC (Py-GC) is a routine tool for characterization of polymers. However, the pyrogram is often complicated and significant peak overlap in the entire pyrogram is frequently observed. Pyrolysis comprehensive two-dimensional GC (Py-GC X GC) well separates polar fragments from non-polar fragments in the entire pyrogram. The key benefit to interpretation of polymer structure by Py-GC X GC is visualization of the fragment structural distribution, which gives us a new insight into the polymer structure and pinpoints differences among polymers. The results for several different kinds of polymers will be presented to demonstrate this new technology.

“A Novel Technique for Polymer Additives Analysis by Pyrolysis Comprehensive Two-Dimensional Gas Chromatography (Py-GC X GC)”
Shayne Green, Kefu Sun , Bruce Gerhart, and Bill Winniford - The Dow Chemical Company

Identification of additives in polymer products is tedious and time consuming and requires many different analytical methods. In some situations, the additives may not be identified because of loss of the additive during sample preparations or analyses. Application of pyrolysis gas chromatography (GC) to identification of fragments from additives is difficult because of interferences from the complex polymer matrix and the small concentration levels of these fragments. In comprehensive two dimension GC (2D GC; GC X GC) the polar additives fragments can be separated from the non-polar matrix fragments in the second dimension. With 2D GC there is a significant improvement in selectivity and sensitivity, which allows for identification of additives in polymer samples. The enhanced selectivity and sensitivity of py-GC x GC for the determination of additives in polymer will be presented.

“A Heart-Cut Two-Dimensional GC System with Direct Injection and Pulsed Discharge Electron Capture Detector for Low ppb Trichloroanisole”
James Griffith, April Boone, Bill Winniford and Kefu Sun - The Dow Chemical Company

A new method using direct injection and heart-cut two-dimensional GC with a pulsed electron capture detector for the analysis of low ppb level of 2,4,6-trichloroanisole was developed. 2,4,6-trichloroanisole is commonly found in wine cork which mainly contributes to a mouldy and musty off-flavor. Compared to methods using GC-MS or GC-radioactive ECD with solvent extraction, or solid phase microextraction for sample pretreatment, the pulsed discharge electron capture detector is non-radioactive and has the same performance as the radioactive ECD. Heart-cut 2D GC with Direct injection reduces the analysis cycle and greatly enhances GC resolution and signal intensity.

“Evolutions of Chemical Packaging- How To Make Your Lab Safer and More Cost-Effective.”
Judith Corona-Karpowicz - ACS Chemicals, Liquid Handling and Safety Products - EM Science

The discussion will cover the differences in chemical packaging and how some packaging choices translate into safer laboratories. Also covered will be how packaging choices can reduce a laboratory's disposal costs while improving a lab's ability to recycle empty packaging. Talk will discuss various options available and will include a demonstration of new packaging innovations available through EM Science including a new recyclable poly-coated glass bottle and new all-corrugated solvent carton.

“80 Second Simulated Distillation Utilizing a Column Module Attached Externally to the Gas Chromatographic Oven”
Joaquin Lubkowitz, Roberto Meneghini, Steve Elliott, Separation Systems, Inc. Robert Mustacich, RV Scientific,Santa Barbara, California

A new module has been developed for the application of fast simulated distillation (C5-C44)in which the column is attached to the outside of the gas chromatographic oven. This allows for complete thermal control of the transfer lines which are housed in the GC oven. Good symmetrical peak shape is obtained for the C38-C44 peaks which usually are difficult to elute in fast chromatography.

“SimDis Expert V7.0- 7.3x and Hydrocarbon Expert V3.0-3.X”
Roberto I Meneghini, Joaquin Lubkowitz - Separation Systems, Inc

Training in the use of new features of all 7.x versions of simulated distillation and the new features of version 3.x software for detailed hydrocarbon analysis including the use of sulfur simulated distillation and including the use our proprietary "pattern recognition feature" for fast identifications during DHA analysis. Training will also be provided in the use and benefits of three dimensional color graphics and reporting. Attend the workshop, learn to use the new features of the upgrades and qualify to download certain new upgrades free from our website.

“Karl Fischer Titration: Quantifying Water in Lube Oils”
Terrance Grasty - EM Science

Petroleum samples, especially lube oils, can differ substantially in property and characteristic and can contain varying amounts of water. Whether samples contain 10 ppm water, 10% water, are prone to cause interference, or are next to impossible to titrate directly, the perfect solution can be found by using the right reagents and instruments. This presentation will discuss how new advancements in KF instrumentation and selecting the right reagents can minimize problems associated with analyzing lube oils for water content.

“New Ion Exchange Columns to Achieve Difficult Separations for Both Anions and Cations”
Lisa Lenehan, Andy Woodruff, Maria A. Rey, Rosanne Slingsby, Nebojsa Avdalovic, and Chris Pohl - Dionex Corporation

This paper introduces two new ion exchange columns that address the challenge of separating both hydrophilic and hydrophobic compounds in a single run. For example, the separation of amines can mean anything from short-chained monoamines, which are hydrophilic, to the long-chained or aromatic polyamines, which are very hydrophobic. When the common inorganic cations are added to the mix, the chromatography can be a challenge. A new low capacity, hydrophilic cation column will be shown that successfully achieves these separations in a single run with a single eluent blend. For anions, a novel approach to this separation challenge is demonstrated by a new cryptand-based anion exchanger which introduces the new concept of capacity gradients. The actual capacity of the column itself can be adjusted simply by changing the mobile phase between LiOH, NaOH, and KOH during the run. The result is the separation of hydrophilic and hydrophobic compounds with excellent efficiencies in a single run.

“Rapid Determination of Polymer Additives, Nutraceuticals, and Consumer Products by Accelerated Solvent Extraction (ASE)”
Lisa Lenehan, Rich Carlson, Sheldon Henderson, Bruce Richter, and John Ezzell - Dionex Corporation

Accelerated solvent extraction (ASE), first introduced in 1995 to environmental laboratories, is an innovative approach to liquid-solid extractions. Its benefit - fast extractions with minimal solvent - is now being utilized for other applications outside the traditional environmental lab setting. New applications to be presented in this paper include the quality control assessment of tobacco, cosmetics, natural products from plants, flavors, fragrances, sunscreens and antacids. ASE has also been applied to the extraction of polymer additives such as antioxidants, slip agents, and UV stabilizers. Other successful ASE applications include extracting plasticizers from polyvinyl chloride and oils from rubber. The results and recoveries will be compared to traditional methods such as sonication and Soxhlet extraction.

“Advances in Benchtop Quadrupole Mass Spectrometry for Ion and Liquid Chromatography (IC/MS and LC/MS)”
Matthew Neely, William C. Schnute, and Chris Loran - Dionex Corporation

As mass spectrometry becomes the detector of choice for chromatographers, the benefits and enhanced MS features of the instrumentation must be carefully considered. Historically, HPLC methods have been developed using involatile buffers that improve chromatographic separations. However, these mobile phases could cause degradation in the signal by contamination or blockage of the Atmospheric Pressure Ionization (API) sources. Here we will present data highlighting chromatography using involatile buffers with an enhanced self-cleaning API interface. Innovative design features allow for rapid mode changing that maintains system performance. We will show augmented detection capabilities by the use of enhanced interfacing designs that greatly improve the performance of IC/MS, which operates at lower mass ranges than traditionally used in LC/MS. General requirements for MS detection have also been addressed including reduced space, mass range extension, and rapid system configuration. Implementation of data handling concepts specifically designed for chromatography, including real time data display during acquisition, customized display panels for instrument control, and user defined reporting formats will be presented.

“On-line Electrolytic Devices for Reagent Free Ion Chromatography”
Matthew Neely, Yan Liu, Victor Barreto, Zhongqing Lu, Chris Pohl, and Nebojsa Avdalovic - Dionex Corporation

Dilute solutions of acids, bases, and salts are commonly used as chromatographic eluents in ion chromatography. Traditionally, these eluents are prepared off-line from reagent grade chemicals. The off-line preparation can be tedious and prone to operator errors, and often introduces contaminates that can cause undesirable chromatographic baseline artifacts or irreproducible retention times of target analytes. Therefore, there is a need for improved methods of preparing high purity eluents for ion chromatography. We have recently developed novel electrolytic devices that can be used to produce electrochemically high purity electrolyte solutions for use in everyday ion chromatography using deionized water as a carrier stream. In this presentation, we will describe the principles and operation of the automated on-line electrolytic devices, and demonstrate the advantages of using these devices in isocratic as well as gradient applications.

“Determination of Total Sulfur Content in Petrochemical Samples Using a Pulsed Flame Photometric Detector (PFPD)”
Laura Chambers, Michael L. Duffy - OI Analytical

There are over a dozen tests methods available for total sulfur determination, each with its own benefits and difficulties. The Pulsed Flame Photometric Detector (PFPD) has the advantage of being an equimolar response detector; the sulfur's chemiluminescence response is independent of a compound's molecular structure. This feature allows quantitation of the sulfur content in complex samples. Calibration with a single sulfur compound or mix will allow quantitation of the sulfur content in individual GC peaks or complex chromatographic patterns. Several examples illustrating different approaches to total sulfur quantitation using the PFPD are described in this poster.

“Total Sulfur Analysis in Petroleum Products Using a Pulsed Flame Photometric Detector (PFPD)”
Laura Chambers, Michael L. Duffy - OI Analytical

The Pulsed Flame Photometric Detector (PFPD) is an ideal choice for determination of total sulfur content in petrochemical matrices because of its essentially infinite selectivity for sulfur, its exceptional sensitivity, its low maintenance requirements, and its long-term stability. Careful selection and optimization of system parameters is essential. This paper will discuss some factors that must be taken into account for this type of analysis including column selection and temperature programming, optimizing detector conditions, and simple techniques for circumventing the "quenching" of the sulfur signal by coeluting hydrocarbon peaks. Examples from a range of real world samples will be presented.

“Initial Experiences From the Field With the OI Analytical Sulfur-Pro 3200”
Laura Chambers, Michael L. Duffy - OI Analytical

The OI Analytical S-PRO 3200 Series GC System is a turnkey solution for the analysis of volatile sulfur compounds in light hydrocarbon streams such as propylene, propane, and natural gas. It is an exceptionally stable and dependable system with outstanding accuracy and repeatability, and requires little or no maintenance. Initial experiences from field installations of the S-PRO 3200 demonstrate that the sulfur selectivity of the PFPD allows it to be used where hydrocarbon background or other factors may otherwise be expected to cause interference. Results from petrochemical applications will be presented, including calibration techniques, linearity, accuracy, and repeatability.

“Improved Performance and Productivity of Purge-and-Trap Analyses”
Laura Chambers, Michael L. Duffy - OI Analytical

The broad range of chemistries represented by the current USEPA volatile lists pose a challenge to the analytical chemist. Method performance criteria must be met for all target compounds simultaneously, in spite of a wide variability in boiling points, polarity, solubility in water, purge efficiencies, and affinity for trap sorbents. In addition, the increasing workloads in commercial laboratories demand that analytical cycle times be shortened to maximize throughput, while still maintaining high standards for method performance. A selection of factors that affect overall cycle time and method performance will be discussed. Data from the new PT Express are presented.

“Innovations in High Pressure Liquid Injection Technique for Gas Chromatography Pressurized Liquid Injection System (PLIS T)”
Richard Tymko, Transcendent Enterprises, Alberta, Canada Jim Luong, Ronda Gras, and Bill Winniford, Dow Chemical Canada Transcendent Enterprise and Dow Chemical Canada

Innovations in High Pressure Liquid Injection Technique for Gas Chromatography - Pressurized Liquid Injection System (PLIS) Richard Tymko1 Ronda Gras2 , Jim Luong2 and Bill Winniford3 1Transcendent Technologies, Edmonton, Alberta, Canada; e-mail address: rrtymko@transcendent.ca 2 Dow Chemical Canada, P.O. Bag 16, Highway 15, Fort Saskatchewan, Alberta, Canada, T8L 2P4; e-mail address: luong@dow.com 3 Dow Chemical, Texas Operations, 2301 Brazosport, Freeport, TX, USA; e-mail address: bwinniford@dow.com Keywords: Gas chromatography, pressurized liquid Injection, volatile liquids, liquid hydrocarbons, PLIS Abstract: In gas chromatography, highly volatile liquids are commonly injected with injection devices such as high pressure syringes, piston valves, liquid rotary sampling valves, or vapourizing regulators. While these techniques are adequate in some cases, there are known deficiencies. For instance, commercially available high pressure syringes have a maximum pressure range of less than 27.6 bar (400 psig), thus precluding them for use with very light hydrocarbons such as liquid ethane. The design of piston valves such as Bendix or Mess Und Apparatetechnik (MAT) types minimized sample fractionation, but these valves have a typical maximum pressure limit of 55.2 bar (800 psig). Yet another limitation of the piston valve is due to its size, it is rather cumbersome to install on a bench-top gas chromatograph. Liquid rotary valves and heated vapourizing regulators can handle very high pressure of up to 344.7 bar (5000 psig); however, fractionation commonly occurs especially in samples with wide boiling point ranges as in the case of diesel fuel in propane. A new sampling valve has been introduced that overcome many of the limitations cited. Pressurized Liquid Injection System (PLIST) enables a pressurized fluid to be injected directly into a gas chromatograph via a conventional split/splitless injection port. Some of the highlights of the injection valve include compact size (10 x 3 x 4 cm) as shown in This reduces void volume, cold spots, surface active sites, and sample handling. Sample loop sizes ranging from 0.2 to 20 uL with various seals materials such as TeflonT and other polymeric materials are available. While the valve has a specification of helium leak-free rating of 82.7 bar (1200 psig), on the valves tested, helium leak-free of up to 144.8 bar (2100 psig) was attained. This clearly demonstrated the valve is capable of handling the most demanding liquid hydrocarbon such as ethylene. In terms of design, the valve has the following characteristics: a) An integrated pneumatic actuator to manipulate the sampling shaft. b) A sampling shaft having a channel which is reciprocal between a sampling position and an injecting position. c) Seals and compression fittings to maintain appropriate set pressure. d) A coupling that connects the valve directly onto a septumless injection port. Despite some rectifiable limitations, the valve was found to be well designed, reliable, and easy to maintain. This illustrates the valve capability to inject solutes with wide range of boiling points. Valve performance and chromatographic applications will be featured in this poster. PLIS T is a trademark of Transcendent Technologies, Edmonton, Canada Teflon T is trademark of Dupont De Nemours, Wilmington, Delaware, USA References: 1. Bowen, B. B., et al., "High Precision Sampling for Chromatographic Separations", Analytical Chemistry, vol. 45 number 14, page 2185-2191, November 1973. 2. Spolnicki J., "A Chromatographic Unit for Automatic Sampling for Kinetic Study", Journal of Applied Chemistry, January 1963. 3. Ruiz F.A. et al., "Constant Pressure Loaded Shaft Seal", US Patent 5,277,073, January 11, 1994 4. Simeroth, et al., "Fluid Sampling for gas chromatograph with modified sampling valve", US Patent 5,150,601, September 29, 1992. 5. Transcendent Technologies, PLIS Operating Manual, revision 1.0, March, 2002, www.transcendent.ca

“New Sulfur Regulations And Catalysts And Their Impact On Low Level Nitrogen And Sulfur Analysis”
Tim Laughlin, Lindsey Pyron, Arthur Van Strien, Peter Veth - EST Analytical

Refineries worldwide are investing heavily to comply with the new fuel specifications. The stringent compliance rule for the maximum content of 15 mg/kg of sulfur in diesel and 30 mg/kg for gasoline forces the industry to re-evaluate their current refining, distribution and quality control methods. Since the future 15 mg/kg ceiling will be the maximum acceptable sulfur level at retail stations by September 2006, more stringent specifications for pipelines will be necessary to reduce variability caused by contamination. Modern desulfurization employs hydrotreating technology, in which dedicated catalysts are used. Of the many sulfur compounds present in fuels, some are easier removed by hydrogenation than others. During their lifetime, catalysts gradually lose their activity. Among many reasons for this is the increased poisoning effect of nitrous compounds, which show a distinct affinity for adhesion to the active sites on the catalyst. It is therefore necessary to determine nitrogen levels in fuels and to take corrective measures if the nitrogen levels prove to be too high. One vendors approach to improve sensitivity and reproducibility to consistently achieve low limits of detection is presented.

“The Analysis of Trace Levels of Impurities in High Purity Carbon Dioxide”
Clarence S. Wentzel - Arnel Inc.

For both health and economic reasons, accurate analyses of carbon dioxide have become critical in the beverage industry. Both producers and purchasers have struggled with the technologies available to produce reliable measurements in plant like environments. Over the last four years, Arnel has developed a dedicated family of analyzers that measure ppb levels of key impurities in carbon dioxide. A complete system is configured with six independent channels of chromatography integrated into two PerkinElmer AutoSystem gas chromatographs controlled by a TotalChrom Chromatography Workstation. Models are available with a User Interface to support complete plant sampling and automation. A key focus of the analyzer is the selection of a SCD for sulfur compound measurements and the adoption of an integral permeation chamber for calibration. Each channel is described to include sampling, chromatography, calibration and precision. Due to poorly engineered sampling and inlet systems, certain impurities, especially hydrogen sulfide are often underreported. This underreporting leads to the use of CO2 that should be rejected. Proper design and sampling techniques as well as materials of construction are reviewed. Finally, the integration of this analyzer system into both production and bottling plants is described.