Thermodesorption Method Research Articles

Hydrocarbon gases in the crystalline rocks of the Gravberg-1 well, Swedish deep gas project

Desorbed gas analyses of cuttings from the Gravberg—1 well, the culmination of the Swedish deep gas project, were undertaken every 100 m from 219 to 5907 m. A sample at 6517 m, from sidetrack 2, was also included. The desorbed gas method performed by hot acid treatment in an evacuated system was superior to both ball mill crushing and thermodesorption methods. Two types of hydrocarbon gases were found in trace quantities. One type associated with the dolerite sills was an isotopically heavy, δ 13C 1: −11 to −15‰, dry gas, with a methane content up to 98%. The other type, occurring throughout the granitic rocks, was an isotopically lighter gas, δ 13C 1: −21 to −39 ‰, containing 30–45% of C 2C 4 olefins and paraffins were present in almost equal amounts in the second type of gas. The dry gas observed in the dolerites is assumed to be abiogenic gas existing in inclusions of basic minerals which react with acid during the analytical procedure. The other type of hydrocarbon gas is thought to be formed from H 2 and CO 2 by a catalytic reaction since it is mainly associated with the magnetic fraction of the rock. A Fischer-Tropsch reaction over a magnetite catalyst is the most likely reaction since it produces both paraffins and olefins. Studies on thin sections of cores and coarse cuttings suggest that the wet gas is not isolated in inclusions and the changes with time observed for a few thin sections indicate that it diffuses quite freely. The potential risks of contamination from drilling fluids and bit metamorphism were examined by comparing the hydrocarbon results with changes in the mud system, rate of penetration and bit life. Hydrocarbon analyses of a few mud additives were included as well. The result of these examinations plus the results of hydrocarbon analyses of cores from pilot core holes in the Siljan Crater suggest that the hydrocarbons observed in the cuttings are indigeneous. Comparing the results of the present study with other hydrocarbon occurrences outside of the Siljan Crater indicates that the hydrocarbons found in the Gravberg—1 well occur widespread in crustal rocks.

Oxygen thermodesorption from Pd/MgO catalysts

O2 interaction with 0.5 mass. % Pd/MgO catalyst at T=298–873 K and\(P_{O_2 } \)=100 kPa has been studied by thermodesorption method. Four peaks attributed to oxygen evolved with Tmax=413, 893, 1113 and 1353 K, Edes=25, 144, 360 and ≥500 kJ/mol have been found.

A thermodesorption study of the hydrogenolysis of heteronuclear compounds on Al-Co-Mo catalysts and their components

1. Thermodesorption methods have been used to show that hydrogen adsorbs on MS in both molecular and atomic forms to form SH groups. It is suggested that thiophene adsorbs only in molecular form. 2. It is the hydrogen which desorbs from the catalyst surface at 50–400°C which is involved in the hydrogenolysis of thiophene.

Acid-base and catalytic properties of binary oxides in the oxidative dehydrodimerization of toluene

Acidity and basicity of binary oxide catalysts measured by the CO2 and NH3 thermodesorption method are compared with their catalytic activity in oxidative conversion of toluene. The rate of toluene dehydrodimerization is shown to increase with the catalyst basicity.

Investigation of the chemisorption of hydrogen on sulfided cobalt-molybdenum and commercial aluminum-cobalt-molybdenum catalysts by a thermodesorption method

li1. 2. Hydrogen is adsorbed on the catalysts in question in molecular and dissociated forms. The activation energies of various forms of the adsorption of hydrogen are determined. 3. Hydrogen, desorbed in high-temperature forms in a 300–550° C interval, participates in the hydrodesulfurization reaction of thiophene. The reaction of H2 with thiophene on the surface of the Al2O3- CoO-MoO3 catalyst is facilitated in the presence of an Al2O3 carrier.

Non-stoichiometric oxygen in Cr2O3 catalysts of different dispersities

The content of non-stoichiometric oxygen in Cr2O3 catalysts of different dispersity has been determined by a direct thermodesorption method. A sharp decrease in the content of non-stoichiometric oxygen after calcination of the samples above 500°C was observed.

Study of surface inhomogeneity by the method of thermodesorption

1. A method was proposed for the treatment of experimental thermodesorption data, based on a measurement of the half-width of the thermodesorption peak. 2. The surface of platinum is homogeneous with respect to the adsorption of atomic nitrogen. 3. The interval of energy inhomogeneity in the adsorption of carbon monoxide on platinum was calculated.

ChemInform Abstract: A THERMODESORPTION METHOD FOR THE INVESTIGATION OF HYDROGEN ADSORPTION ON ELECTRODES, ITS APPLICATION TO TUNGSTEN CARBIDE ALONG WITH ELECTROCHEMICAL METHODS

Chemischer InformationsdienstVolume 6, Issue 19 Physical Inorganic Chemistry ChemInform Abstract: A THERMODESORPTION METHOD FOR THE INVESTIGATION OF HYDROGEN ADSORPTION ON ELECTRODES, ITS APPLICATION TO TUNGSTEN CARBIDE ALONG WITH ELECTROCHEMICAL METHODS V. SH. PALANKER, V. SH. PALANKERSearch for more papers by this authorE. N. BAYBATYROV, E. N. BAYBATYROVSearch for more papers by this authorD. V. SOKOLSKY, D. V. SOKOLSKYSearch for more papers by this author V. SH. PALANKER, V. SH. PALANKERSearch for more papers by this authorE. N. BAYBATYROV, E. N. BAYBATYROVSearch for more papers by this authorD. V. SOKOLSKY, D. V. SOKOLSKYSearch for more papers by this author First published: May 13, 1975 https://doi.org/10.1002/chin.197519020AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume6, Issue19May 13, 1975 RelatedInformation

Investigation of the state of hydrogen in a nickel-chromium catalyst by the method of thermodesorption

1. The interaction of hydrogen with an industrial reduced nickel-chromium catalyst was investigated by the method of thermodesorption in the interval 30–300°C. 2. There are four forms of chemisorbed hydrogen on the surface of the catalyst; the nature of the surface inhomogeneity of the catalyst was established, and the activation energies of desorption were determined for all four forms of adsorption. 3. The influence of diffusion on the behavior of thermodesorbed hydrogen was detected.

A thermodesorption method for the investigation of hydrogen adsorption on electrodes; its application to tungsten carbide, along with electrochemical methods

A method for direct determination of hydrogen adsorption on large surface area electrodes or on electro-conductive powders in electrolyte solutions, at any given potential, is proposed. It consists of hydrogen desorption from the electrode by heating (thermodesorption) after complete adsorption and a quantitative chromatographic analysis of the gas collected during thermodesorption. The proposed method was used in this work to investigate hydrogen adsorption on tungsten carbide powder in a H 2SO 4 solution. The potential-dependence of adsorption was found, confirming the authors previous suggestion of an extensive coverage of tungsten carbide by chemisorbed hydrogen and of the potential region of adsorption (up to 0·35–0·4 V). The tungsten carbide surface was also investigated by the method of charging and potentiodynamic curves. Reversibility of these curves up to 0·35–0·4 V is shown. Hydrogen adsorption is correlated with the quantity of electricity calculated from the charging curve and it is shown that a considerable portion of the charge is associated with hydrogen chemisorption but some portion of the total charge is consumed even in the hydrogen region for other non-defined redox processes occurring on the tungsten carbide surface.