Development of a new method for hydrogen isotope analysis of trace hydrocarbons in natural gas samples

Abstract. Chloromethane (CH3Cl) is an important provider of chlorine to the stratosphere but yet lacks detailed knowledge of its budget. Stable isotope analysis is potentially a powerful tool to constrain CH3Cl flux estimates. The largest degree of isotope fractionation is expected to occur for deuterium in CH3Cl in the hydrogen abstraction reactions with its main sink reactant tropospheric OH and its minor sink reactant Cl atoms. We determined the isotope fractionation by stable hydrogen isotope analysis of the fraction of CH3Cl remaining after reaction with hydroxyl and chlorine radicals in a 3.5 m3 Teflon smog-chamber at 293 ± 1 K. We measured the increasing stable hydrogen isotope values of the unreacted CH3Cl using compound specific thermal conversion isotope ratio mass spectrometry. The isotope fractionations of CH3Cl for the reactions with hydroxyl and chlorine radicals were found to be −242 ± 7 mUr (or ‰) and −280 ± 11 mUr, respectively. For comparison, we performed similar experiments using methane (CH4) as the target compound with OH and obtained a fractionation constant of −205 ± 6 mUr which is in good agreement with values previously reported. The observed large kinetic isotope effects are helpful when employing isotopic analyses of CH3Cl in the atmosphere to improve our knowledge of its atmospheric budget.

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Hydrogen-isotope analysis of potentially toxic organic materials employing manganese reduction and disposable nickel-pyrolysis tubes

Chemical Geology ◽

10.1016/s0009-2541(01)00265-0 ◽

2001 ◽

Vol 181 (1-4) ◽

pp. 67-71

Author(s):

J.E. Motz ◽

O. Shouakar-Stash ◽

R.J. Drimmie ◽

T.W.D. Edwards ◽

S.K. Frape ◽

...

Keyword(s):

Hydrogen Isotope ◽

Organic Materials ◽

Isotope Analysis ◽

Manganese Reduction

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To shred roughly or to grind? On the methods of sample preparation of the keratinous material for stable hydrogen isotope analysis

Ecosystem Transformation ◽

10.23859/estr-200407 ◽

2020 ◽

Vol 3 (2) ◽

Author(s):

Maria A. Belova ◽

Alyona A. Zudilova ◽

Dmitry S. Kopylov

Keyword(s):

Sample Preparation ◽

Hydrogen Isotope ◽

Isotope Analysis ◽

Stable Hydrogen Isotope

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A Novel Method to Identify Illegal Diesel Fuel, II: the Use of [1-D]n-Alkane with Stable Hydrogen Isotope Analysis

Chemistry Letters ◽

10.1246/cl.2006.532 ◽

2006 ◽

Vol 35 (5) ◽

pp. 532-533 ◽

Cited By ~ 12

Author(s):

Yaeko Suzuki ◽

Takashi Korenaga ◽

Yoshito Chikaraishi

Keyword(s):

Diesel Fuel ◽

Hydrogen Isotope ◽

Isotope Analysis ◽

Novel Method ◽

Stable Hydrogen Isotope

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Optimization of Long Distance Natural Gas Pipeline Design Proposals Based on Multi-Objective AHM Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.756-759.4309 ◽

2013 ◽

Vol 756-759 ◽

pp. 4309-4313

Author(s):

Feng Juan Dong ◽

Xue Fei Lu

Keyword(s):

Natural Gas ◽

Pressure Ratio ◽

Gas Pipeline ◽

New Method ◽

Long Distance ◽

Natural Gas Pipeline ◽

Delivery Pressure ◽

Design Case ◽

Pipeline Design ◽

Assessment Result

the new method-AHM, and nine parameters which included diameter, delivery pressure, pressure ratio of the first station, pressure ratios of intermediate stations, number of stations, investment costs of pipeline ,investment costs of stations, investment costs of operation ,equivalent cost, have been selected to evaluate design projects of the long distance natural gas pipeline. The results indicate that attribute AHM matches other methods well. The calculation result of the example indicates that AHM method can get a good assessment result for the multifactor and multi-hierarchy complicated problems. The study provides a new method and technique for designers to select the technical feasible and economic reasonable design case, which has some theoretical and practical value.

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