Equations of state for helium, hydrogen, deuterium, nitrogen, oxygen, carbon monoxide, carbon dioxide, and methane at high temperatures and pressures

2000 ◽  
Vol 38 (3) ◽  
pp. 374-378 ◽  
Author(s):  
V. I. Nedostup ◽  
E. P. Gal’kevich
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
High Temperatures ◽  
Equations Of State ◽  
Hydrogen Deuterium

The combustion of methane at high temperatures

1954 ◽  
Vol 227 (1168) ◽  
pp. 73-93 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Activation Energy ◽  
Carbon Monoxide ◽  
Apparent Activation Energy ◽  
High Temperatures ◽  
Final Stage ◽  
Flow System ◽  
Oxidation Products ◽  
Reaction Proceeds ◽  
Effect Of Surface

The combustion at about 1000°C of methane/air mixtures containing up to 5% of methane has been studied using a flow system. Under such conditions the reaction takes place in a few milliseconds. It is little influenced by surface, is retarded by methane and accelerated by oxygen. Below 500 to 600°C there appears to be a change in the kinetics, but no definite trend of apparent activation energy has been distinguished over the whole temperature range. The effect of surface on the reaction increases at lower temperatures. The reaction proceeds via formaldehyde and carbon monoxide, and the further oxidation of the latter is apparently inhibited by the former or by its oxidation products. This results in an accumulation, in the later stages of reaction, of carbon monoxide, which oxidizes rapidly or ignites when the formaldehyde and the methane have been consumed. Carbon dioxide does, however, appear to some extent before this final stage. Hydrogen also appears, and although its oxidation is retarded in the presence of methane, when the methane oxidizes the hydrogen goes ‘in step’ with it. In the presence of hydrogen the oxidation temperature of carbon monoxide is reduced to that of the hydrogen, but on addition of methane the hydrogen and methane are oxidized together, whilst carbon monoxide remains until the methane has disappeared. Ethane also inhibits the combustion of carbon monoxide, but less effectively than an equal amount of methane.

scholarly journals Controlled atmosphere GMAW welding of transportation vehicles and production machines parts made from 30MnB5 steel

2018 ◽  
Vol 216 ◽  
pp. 03001 ◽  
Author(s):  
Evgeny Ivanayskiy ◽  
Aleksei Ishkov ◽  
Aleksandr Ivanayskiy ◽  
Iakov Ochakovskii
Keyword(s):  
Mechanical Properties ◽  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Chemical Composition ◽  
Controlled Atmosphere ◽  
Shielding Gas ◽  
Reducing Atmosphere ◽  
Metal Composition ◽  
Gmaw Welding ◽  
Welding Materials

The paper studies the influence of shielding gas on the composition and the structure of weld joint metal of 30MnB5 steel applied in essential parts of automobiles and tractors. The welding was performed in inert, oxidizing and reducing atmospheres. It was established that TIG welding with argon used as shielding gas did not provide the required mechanical properties when using conventional welding materials. Carbon dioxide during MAG welding caused partial burning of alloying elements. Carbon monoxide used as shielding gas was proved to form reducing atmosphere enabling to obtain chemical composition close to the base metal composition. Metallographic examinations were carried out. The obtained results provided full-strength weld, as well as the required reliability and durability of welded components and joints.

Low-Carbon Monoxide Hydrogen by Sorption-Enhanced Reaction

2003 ◽  
Vol 1 (1) ◽  
Author(s):  
Douglas P Harrison ◽  
Zhiyong Peng
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Hydrogen Production ◽  
Proton Exchange Membrane ◽  
Primary Energy ◽  
Proton Exchange ◽  
Raw Material ◽  
Impurity Level ◽  
Low Carbon ◽  
Enhanced Production

Hydrogen is an increasingly important chemical raw material and a probable future primary energy carrier. In many current and anticipated applications the carbon monoxide impurity level must be reduced to low-ppmv levels to avoid poisoning catalysts in downstream processes. Methanation is currently used to remove carbon monoxide in petroleum refining operations while preferential oxidation (PROX) is being developed for carbon monoxide control in fuel cells. Both approaches add an additional step to the multi-step hydrogen production process, and both inevitably result in hydrogen loss. The sorption enhanced process for hydrogen production, in which steam-methane reforming, water-gas shift, and carbon dioxide removal reactions occur simultaneously in the presence of a nickel-based reforming catalyst and a calcium-based carbon dioxide sorbent, is capable of producing high purity hydrogen containing minimal carbon monoxide in a single processing step. The process also has the potential for producing pure CO2 that is suitable for subsequent use or sequestration during the sorbent regeneration step. The current research on sorption-enhanced production of low-carbon monoxide hydrogen is an extension of previous research in this laboratory that proved the feasibility of producing 95+% hydrogen (dry basis), but without concern for the carbon monoxide concentration. This paper describes sorption-enhanced reaction conditions – temperature, feed gas composition, and volumetric feed rate – required to produce 95+% hydrogen containing low carbon monoxide concentrations suitable for direct use in, for example, a proton exchange membrane fuel cell.

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