Carbon monoxide-hydrogen catalytic conversion

Transition metal carbides (mainly of W and Mo) have been shown to be effective catalysts in some chemical reactions that are usually catalyzed by noble metals such as Pt and Pd (ref.1). Their remarkable physical properties added to lower cost and better availability could make them good candidates for substitute materials to noble metals in automobile exhaust catalysis. Hence, for this purpose, we have prepared several catalysts of tungsten carbide and W,Mo mixed carbides supported on y alumina with different Mo/W atom ratios. The surface composition has been studied by XPS while the quantitative determination of catalytic sites has been obtained by selective chemisorption of hydrogen and of carbon monoxide. The catalytic performances of these catalysts have been evaluated in the simultaneous conversion of carbon monoxide, nitric oxide and propane from a synthetic exhaust gas. 

Typical catalytic reactions that have been investigated, in some detail, using this approach include hydrocarbon conversion on platinum and modified platinum surfaces (isomerization, hydrogenolysis, hydrogenation, dehydrogenation and cyclization), dehydrosulfurization on molybdenum, ammonia synthesis on iron, and carbon monoxide hydrogenation on iron. 

In the early 1920s Badische Arulin- und Soda-Fabrik aimounced the specific catalytic conversion of carbon monoxide and hydrogen at 20—30 MPa (200—300 atm) and 300—400°C to methanol (12,13), a process subsequendy widely industrialized. At the same time Fischer and Tropsch aimounced the Synth in e process (14,15), in which an iron catalyst effects the reaction of carbon monoxide and hydrogen to produce a mixture of alcohols, aldehydes (qv), ketones (qv), and fatty acids at atmospheric pressure. 

Synthesis Gas Chemicals. Hydrocarbons are used to generate synthesis gas, a mixture of carbon monoxide and hydrogen, for conversion to other chemicals. The primary chemical made from synthesis gas is methanol, though acetic acid and acetic anhydride are also made by this route. Carbon monoxide (qv) is produced by partial oxidation of hydrocarbons or by the catalytic steam reforming of natural gas. About 96% of synthesis gas is made by steam reforming, followed by the water gas shift reaction to give the desired H2 /CO ratio. 

Twenty-Five Years of Synthesis of Gasoline by Catalytic Conversion of Carbon Monoxide and Hydrogen Helmut Pichler... 

Pichler, H. 1952. Twenty-five years of synthesis of gasoline by catalytic conversion of carbon monoxide and hydrogen. Adv. Catal. 4 271-341. 

After the reforming reaction, the gas is quickly cooled down to about 350 450 °C before it enters the (high-temperature) water-gas shift reaction (CO shift). Here, the exothermic catalytic conversion takes place of the carbon monoxide formed with steam to hydrogen (H2) and carbon dioxide (C02) in the following reaction ... 

Catalytic conversion of l-Octanol-2-d to ketone A quantity (29.7 ml.) of l-octanol-2-d was charged (space velocity 0.2) to a 5-mm. reactor tube containing 18 ml. of 8- to 10-mesh chromium oxide catalyst maintained at 400°. The 27.7 ml. of liquid product was fractionated in a concentric-tube etjlumn. A 60.6% yield of di-n-heptyl ketone was obtained. Approximately 17% of the alcohol was recovered "unconverted. Mass spectrometric analysis of the gaseous product showed the atomic ratio of deuterium to hydrogen to be 0.106. The molal yields of deuterium, hydrogen, and carbon monoxide produced per mole of ketone were 0.216, 2.040, and 0.815 respectively. 

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