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Book Water Quality  Determination of 16 Polycyclic Aromatic Hydrocarbons  PAH  in Water  Method Using Gas Chromatography with Mass Spectrometric Detection  GC MS

Download or read book Water Quality Determination of 16 Polycyclic Aromatic Hydrocarbons PAH in Water Method Using Gas Chromatography with Mass Spectrometric Detection GC MS written by British Standards Institute Staff and published by . This book was released on 1911-08-31 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water, Quality, Water testing, Chemical analysis and testing, Determination of content, Aromatic hydrocarbons, Polynuclear aromatic hydrocarbons, Gas chromatography, Mass spectrometry, Extraction methods of analysis, Potable water, Ground water, Wastes

Book Water Quality  Determination of Selected Polycyclic Aromatic Hydrocarbons  PAH  in Whole Water Samples  Method Using Solid Phase Extraction  SPE  with SPE Disks Combined with Gas Chromatography Mass Spectrometry  GC MS

Download or read book Water Quality Determination of Selected Polycyclic Aromatic Hydrocarbons PAH in Whole Water Samples Method Using Solid Phase Extraction SPE with SPE Disks Combined with Gas Chromatography Mass Spectrometry GC MS written by British Standards Institute Staff and published by . This book was released on 1915-09-30 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water, Quality, Water testing, Chemical analysis and testing, Determination of content, Polynuclear aromatic hydrocarbons, Aromatic hydrocarbons, Potable water, Chromatography, Thin-layer chromatography, Fluorimetry, Extraction methods of analysis

Book Investigations Into the Extraction and the Determination of Polycyclic Aromatic Hydrocarbons  PAHs  from Water by Solid phase Extraction and Capillary Gas Chromatography  Mass Spectrometry

Download or read book Investigations Into the Extraction and the Determination of Polycyclic Aromatic Hydrocarbons PAHs from Water by Solid phase Extraction and Capillary Gas Chromatography Mass Spectrometry written by Mohamed Elrutb and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Factors affecting the detennination of PAHs by capillary GC/MS were studied. The effect of the initial column temperature and the injection solvent on the peak areas and heights of sixteen PAHs, considered as priority pollutants, USillg crosslinked methyl silicone (DB!) and 5% diphenyl, 94% dimethyl, 1% vinyl polysiloxane (DBS) columns was examined. The possibility of using high boiling point alcohols especially butanol, pentanol, cyclopentanol, and hexanol as injection solvents was investigated. Studies were carried out to optimize the initial column temperature for each of the alcohols. It was found that the optimum initial column temperature is dependent on the solvent employed. The peak areas and heights of the PAHs are enhanced when the initial column temperature is 10-20 c above the boiling point of the solvent using DB5 column, and the same or 10 C above the boiling point of the solvent using DB1 column. Comparing the peak signals of the PAHs using the alcohols, p-xylene, n-octane, and nonane as injection solvents, hexanol gave the greatest peak areas and heights of the PAHs particularly the late-eluted peaks. The detection limits were at low pg levels, ranging from 6.0 pg for fluorene t9 83.6 pg for benzo(a)pyrene. The effect of the initial column temperature on the peak shape and the separation efficiency of the PARs was also studied using DB1 and DB5 columns. Fronting or splitting of the peaks was obseIVed at very low initial column temperature. When high initial column temperature was used, tailing of the peaks appeared. Great difference between DB! and.DB5 columns in the range of the initial column temperature in which symmetrical.peaks of PAHs can be obtained is observed. Wider ranges were shown using DB5 column. Resolution of the closely-eluted PAHs was also affected by the initial column temperature depending on the stationary phase employed. In the case of DB5, only the earlyeluted PAHs were affected; whereas, with DB1, all PAHs were affected. An analytical procedure utilizing solid phase extraction with bonded phase silica (C8) cartridges combined with GC/MS was developed to analyze PAHs in water as an alternative method to those based on the extraction with organic solvent. This simple procedure involved passing a 50 ml of spiked water sample through C8 bonded phase silica cartridges at 10 ml/min, dried by passing a gentle flow of nitrogen at 20 ml/min for 30 sec, and eluting the trapped PAHs with 500 Jll of p-xylene at 0.3 ml/min. The recoveries of PAHs were greater than 80%, with less than 10% relative standard deviations of nine determinations. No major contaminants were present that could interfere with the recognition of PAHs. It was also found that these bonded phase silica cartridges can be re-used for the extraction of PAHs from water.

Book PAHs

    Book Details:
  • Author : Peter E. T. Douben
  • Publisher : John Wiley & Sons
  • Release : 2003-07-25
  • ISBN : 047086429X
  • Pages : 404 pages

Download or read book PAHs written by Peter E. T. Douben and published by John Wiley & Sons. This book was released on 2003-07-25 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbons (PAHs), or polyarenes, are one of the largest and most structurally diverse class of organic molecules known. High percentages of polyarenes, representing a wide range of molecular sizes and structural types, are present in coal tars and petroleum residues. The major sources of PAHs are crude oil, coal and oil shale. The fuels produced from these fossil sources constitute the primary source of energy for the industrial nations of the world, and the petrochemicals from these raw materials are the basis of the synthetic fibre and plastics industries. PAHs are however, widespread pollutants and their impact on the environment and human health must be monitored and controlled. This book will review and assess our scientific understanding of the ecological exposure and effects PAHs have in different environments and habitats. It will accomplish this by taking the recipients of the pollution in the environment as starting points and working its way back through pathways to access what is required for our understanding of effects and rationale for control. Although this book will concentrate on ecological exposure of PAHs, the general impacts of PAHs on human populations will be touched upon. It is thought to be the first book to focus on the ecological aspects of PAHs.

Book Characterization of Waste  Determination of Polycyclic Aromatic Hydrocarbons  PAH  in Waste Using Gas Chromatography Mass Spectrometry  GC MS

Download or read book Characterization of Waste Determination of Polycyclic Aromatic Hydrocarbons PAH in Waste Using Gas Chromatography Mass Spectrometry GC MS written by British Standards Institute Staff and published by . This book was released on 2009-03-31 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wastes, Sludge, Soils, Soil pollution, Bitumens, Chemical analysis and testing, Determination of content, Aromatic hydrocarbons, Polynuclear aromatic hydrocarbons, Gas chromatography, Mass spectrometry, Extraction methods of analysis

Book Water Quality  Determination of 15 Polycyclic Aromatic Hydrocarbons  PAH  in Water by HPLC with Fluorescence Detection After Liquid Liquid Extraction

Download or read book Water Quality Determination of 15 Polycyclic Aromatic Hydrocarbons PAH in Water by HPLC with Fluorescence Detection After Liquid Liquid Extraction written by British Standards Institute Staff and published by . This book was released on 2002-09-17 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water, Quality, Water testing, Chemical analysis and testing, Determination of content, Aromatic hydrocarbons, Polynuclear aromatic hydrocarbons, Liquid chromatography, Extraction methods of analysis, Fluorescence, Potable water, Ground water

Book Characterization of waste   Determination of polycyclic aromatic hydrocarbons  PAH  in waste using gas chromatography mass spectrometry  GC MS

Download or read book Characterization of waste Determination of polycyclic aromatic hydrocarbons PAH in waste using gas chromatography mass spectrometry GC MS written by and published by . This book was released on 2008 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Identification and Quantitation of Complex Polycyclic Aromatic Hydrocarbon Mixtures in Environmental Samples Using Comprehensive Two dimensional Gas Chromatography with Time of flight Mass Spectrometry

Download or read book The Identification and Quantitation of Complex Polycyclic Aromatic Hydrocarbon Mixtures in Environmental Samples Using Comprehensive Two dimensional Gas Chromatography with Time of flight Mass Spectrometry written by Carlos Andres Manzano and published by . This book was released on 2012 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants and are mostly products of the incomplete combustion of organic material. PAHs are often found in environmental samples as a complex mixture of isomers. In addition, the same sources that produce complex PAH mixtures also produce other poorly characterized mixtures of organic compounds, commonly referred to as an unresolved complex mixture (UCM), that act as matrix interferences in the chromatographic analysis of samples. Conventional one-dimensional chromatographic techniques, such as gas chromatography coupled to mass spectrometry (GC/MS), are not sufficient for the analysis and quantitation of complex PAH mixtures present in environmental samples due to the high degree of overlap in compound vapor pressures, boiling points, and mass spectral fragmentation patterns. Therefore, the separation and quantitation of complex mixtures of individual PAH compounds in environmental samples requires high chromatographic resolution. Comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GCxGC/ToF-MS) was used for this study. GCxGC/ToF-MS uses two different gas chromatographic columns, with different separation mechanisms, for the analysis of complex environmental samples. In theory, the peak capacity in GCxGC/ToF-MS is equivalent to the product of the individual peak capacities of each column used. However, in practice, this is rarely obtained because of the existing correlation between the two GC columns used. This dissertation is a compilation of three studies related to analytical method development for the identification and quantitation of complex PAH mixtures (including parent-PAHs, alkyl-PAHs, oxy-PAHs, nitro-PAHs, thio-PAHs, chloro-PAHs, bromo-PAHs and PAHs with molecular weight higher than 300 Da) that may be present in environmental samples using novel column combinations in GCxGC/ToF-MS. The use of a liquid crystal column (LC-50) in the first dimension, followed by a nano-stationary phase column (NSP-35) in the second dimension, was evaluated for the separation of a standard PAH mixture containing 97 different PAHs. Two standard reference materials purchased from NIST (NIST SRM1650b - Diesel Particulate Matter and NIST SRM1975 - Diesel Extract) were used, after extraction and cleanup, for method validation and comparison between the commonly used non-polar x polar column combination and the LC-50 x NSP-35 column combination with high orthogonality. As part of the method validation, an aliquot of NIST SRM1975 (Diesel extract), without sample cleanup was also analyzed for PAHs, showing that the LC-50 x NSP-35 column combination was accurate (with an average absolute percent difference of approximately 30%) for the identification and quantitation of complex PAH mixtures in environmental samples, with reduced sample preparation prior to analysis. In addition, the LC-50 x NSP-35 column combination was used for the analysis of PAHs sorbed to polystyrene pellets deployed in an urban bay area as passive water samplers because one-dimensional GC/MS was ineffective due to the presence of a strong unresolved complex mixture (UCM) and matrix interferences.

Book Investigations Into the Determination of Polycyclic Aromatic Hydrocarbons  PAHs  and Polychlorinated Biphenyls  PCBs  by Capillary Gas Chromatography

Download or read book Investigations Into the Determination of Polycyclic Aromatic Hydrocarbons PAHs and Polychlorinated Biphenyls PCBs by Capillary Gas Chromatography written by Xing-Fang Li and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Factors involved in the determination of PAHs (16 priority PAHs as an example) and PCBs (10 PCB congeners, representing 10 isomeric groups) by capillary gas chromatography coupled with mass spectrometry (GC/MS, for PAHs) and electron capture detection (GC/ECD , for PCBs) were studied, with emphasis on the effect of solvent. Having various volatilities and different polarities, solvent studied included dichloromethane, acetonitrile, hexan e, cyclohexane, isooctane, octane, nonane, dodecane, benzene, toluene, p-xylene, o-xylene, and mesitylene. Temperatures of the capillary column, the injection port, the GC/MS interface, the flow rates of carrier gas and make-up gas, and the injection volume were optimized by one factor at a time method or simplex optimization method. Under the optimized conditions, both peak height and peak area of 16 PAHs, especially the late-eluting PAHs, were significantly enhanced (1 to 500 times) by using relatively higher boiling point solvents such as p-xylene and nonane, compared with commonly used solvents like benzene and isooctane. With the improved sensitivity, detection limits of between 4.4 pg for naphthalene and 30.8 pg for benzo[g,h,i]perylene were obtained when p-xylene was used as an injection solvent. Effect of solvent on peak shape and peak intensity were found to be greatly dependent on temperature parameters, especially the initial temperature of the capillary column. The relationship between initial temperature and shape of peaks from 16 PAHs and 10 PCBs were studied and compared when toluene, p-xylene, isooctane, and nonane were used as injection solvents. If a too low initial temperature was used, fronting or split of peaks was observed. On the other hand, peak tailing occurred at a too high initial column temperature. The optimum initial temperature, at which both peak fronting and tailing were avoided and symmetrical peaks were obtained, depended on both solvents and the stationary phase of the column used. On a methyl silicone column, the alkane solvents provided wider optimum ranges of initial temperature than aromatic solvents did, for achieving well-shaped symmetrical GC peaks. On a 5% diphenyl: 1% vinyl: 94% dimethyl polysiloxane column, when the aromatic solvents were used, the optimum initial temperature ranges for solutes to form symmetrical peaks were improved to a similar degree as those when the alkanes were used as injection solvents. A mechanism, based on the properties of and possible interactions among the analyte, the injection solvent, and the stationary phase of the capillary column, was proposed to explain these observations. The effect of initial temperature on peak height and peak area of the 16 PAHs and the 10 PCBs was also studied. The optimum initial temperature was found to be dependent on the physical properties of the solvent used and the amount of the solvent injected. Generally, from the boiling point of the solvent to 10 0C above its boiling point was an optimum range of initial temperature at which cthe highest peak height and peak area were obtained.

Book Green Analytical Chemistry

Download or read book Green Analytical Chemistry written by Justyna Płotka-Wasylka and published by Springer. This book was released on 2019-08-02 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book explains the principles and fundamentals of Green Analytical Chemistry (GAC) and highlights the current developments and future potential of the analytical green chemistry-oriented applications of various solutions. The book consists of sixteen chapters, including the history and milestones of GAC; issues related to teaching of green analytical chemistry and greening the university laboratories; evaluation of impact of analytical activities on the environmental and human health, direct techniques of detection, identification and determination of trace constituents; new achievements in the field of extraction of trace analytes from samples characterized by complex composition of the matrix; “green” nature of the derivatization process in analytical chemistry; passive techniques of sampling of analytes; green sorption materials used in analytical procedures; new types of solvents in the field of analytical chemistry. In addition green chromatography and related techniques, fast tests for assessment of the wide spectrum of pollutants in the different types of the medium, remote monitoring of environmental pollutants, qualitative and comparative evaluation, quantitative assessment, and future trends and perspectives are discussed. This book appeals to a wide readership of the academic and industrial researchers. In addition, it can be used in the classroom for undergraduate and graduate Ph.D. students focusing on elaboration of new analytical procedures for organic and inorganic compounds determination in different kinds of samples characterized by complex matrices composition.Jacek Namieśnik was a Professor at the Department of Analytical Chemistry, Gdańsk University of Technology, Poland. Justyna Płotka-Wasylka is a teacher and researcher at the same department.

Book Water Quality  Determination of Polycyclic Aromatic Hydrocarbons  PAH   Determination of Six Pah by High Performance Thin Layer Chromatography with Fluorescence Detection After Liquid Liquid Extraction

Download or read book Water Quality Determination of Polycyclic Aromatic Hydrocarbons PAH Determination of Six Pah by High Performance Thin Layer Chromatography with Fluorescence Detection After Liquid Liquid Extraction written by British Standards Institute Staff and published by . This book was released on 2005-08-01 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water, Quality, Water testing, Chemical analysis and testing, Determination of content, Polynuclear aromatic hydrocarbons, Aromatic hydrocarbons, Potable water, Chromatography, Thin-layer chromatography, Fluorimetry, Extraction methods of analysis

Book Polycyclic Aromatic Hydrocarbons in Water Sys

Download or read book Polycyclic Aromatic Hydrocarbons in Water Sys written by David J. Futoma and published by Springer. This book was released on 1981-11-05 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Opisane so spektroskopske in kromatografske analize PAH v vodi, njihova topnost, vzorčevanje in predhodno koncentriranje.

Book Novel Improvements on the Analytical Chemistry of Polycyclic Aromatic Hydrocarbons and Their Metabolites

Download or read book Novel Improvements on the Analytical Chemistry of Polycyclic Aromatic Hydrocarbons and Their Metabolites written by Wang Huiyong and published by . This book was released on 2010 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbons (PAH) are important environmental pollutants originating from a wide variety of natural and anthropogenic sources. Because many of them are highly suspect as etiological agents in human cancer, chemical analysis of PAH is of great environmental and toxicological importance. Current methodology for PAH follows the classical pattern of sample preparation and chromatographic analysis. Sample preparation pre-concentrates PAH, simplifies matrix composition, and facilitates analytical resolution in the chromatographic column. Among the several approaches that exist to pre-concentrate PAH from water samples, the Environmental Protection Agency (EPA) recommends the use of solid-phase extraction (SPE). High-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) are the basis for standard PAH identification and determination. Ultraviolet (UV) absorption and room temperature fluorescence detection are both widely used in HPLC, but the specificity of these detectors is modest. Since PAH identification is solely based on retention times, unambiguous PAH identification requires complete chromatographic resolution of sample components. When HPLC is applied to "unfamiliar" samples, the EPA recommends that a supporting analytical technique such as GC-MS be applied to verify compound identification and to check peak-purity HPLC fractions. Independent of the volume of extracted water, the approximate time required to separate and determine the sixteen "priority pollutants" (EPA-PAH) via HPLC is approximately 60min. If additional GC-MS analysis is required for unambiguous PAH determination, the total analysis time will reach 2-3 hours per sample. If the concentrations of target species are found to lie outside the detector's response range, the sample must be diluted and the process repeated. These are important considerations when routine analysis of numerous samples is contemplated. Parent PAH are relatively inert and need metabolic activation to express their carcinogenicity. By virtue of the rich heterogeneous distribution of metabolic products they produce, PAH provide a full spectrum of the complexity associated with understanding the initial phase of carcinogenesis. PAH metabolites include a variety of products such as expoxides, hydroxyl aromatics, quinines, dihydrodiols, dioepoxides, tetrols and water soluble conjugates. During the past decades tremendous efforts have been made to develop bio-analytical techniques that possess the selectivity and sensitivity for the problem at hand. Depending on the complexity of the sample and the relative concentrations of the targeted metabolites, a combination of sample preparation techniques is often necessary to reach the limits of detection of the instrumental method of analysis. The numerous preparation steps open ample opportunity to metabolite loss and collection of inaccurate data. Separation of metabolites has been accomplished via HPLC, capillary electrophoresis (CE) and GC-MS. Unfortunately, the existence of chemically related metabolic products with virtually identical fragmentation patterns often challenges the specificity of these techniques. This dissertation presents significant improvements in various fronts. Its first original component--which we have named solid-phase nano-extraction (SPNE)--deals with the use of gold nanoparticles (Au NPs) as extracting material for PAH. The advantages of SPNE are demonstrated for the analysis of PAH in water samples via both HPLC and Laser-Excited Time-Resolved Shpol'skii Spectroscopy (LETRSS). The same concept is then extended to the analysis of monohydroxy-PAH in urine samples via SPE- HPLC and In-Capillary SPNE-CE. The second original component of this dissertation describes the application of Shpol'skii Spectroscopy to the analysis of polar PAH metabolites. The outstanding selectivity and sensitivity for the direct analysis of PAH at trace concentration levels has made Shpol'skii spectroscopy a leading technique in environmental analysis. Unfortunately, the requirement of a specific guest-host combination--typically a non-polar PAH dissolved in an n-alkane-- has hindered its widespread application to the field of analytical chemistry. This dissertation takes the first steps in removing this limitation demonstrating its feasibility for the analysis of polar benzopyrene metabolites in alcohol matrixes.

Book The Chemical Components of Tobacco and Tobacco Smoke

Download or read book The Chemical Components of Tobacco and Tobacco Smoke written by Alan Rodgman and published by CRC Press. This book was released on 2016-04-19 with total page 2334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Authored by two longtime researchers in tobacco science, The Chemical Components of Tobacco and Tobacco Smoke, Second Edition chronicles the progress made from late 2008 through 2011 by scientists in the field of tobacco science. The book examines the isolation and characterization of each component. It explores developments in pertinent analytical