Carbon monoxide methanol synthesis from

Thermal chlorination of methane was first put on an industrial scale by Hoechst in Germany in 1923. At that time, high pressure methanol synthesis from hydrogen and carbon monoxide provided a new source of methanol for production of methyl chloride by reaction with hydrogen chloride. Prior to 1914 attempts were made to estabHsh an industrial process for methanol by hydrolysis of methyl chloride obtained by chlorinating methane. 

Methanol can also be produced through a two-step process comprising of steam reforming of methane and methanol synthesis from carbon monoxide and hydrogen. The first step of steam reforming of methane consists of the following two reactions ... 

The second step of methanol synthesis from carbon monoxide consists of the following two reactions ... 

Values of Activation Energies of Methanol Synthesis from Carbon Monoxide, Efk), and from Carbon Dioxide, E,(k ), and Adsorption Enthalpies AH and Entropies AS Derived from the Kinetic Model Utilizing Constants in Table IX ... 

At the present moment, almost of methanol has been produced from natural gas through steam reforming followed by synthesis from hydrogen and carbon monoxide. Methanol is a promising fuel in future, because it is easily handled as liquid fuel, compatible with the existing infrastructure of motor vehicles, and wide application for direct burning and fuels for fuel cells. Furthermore, it is widely used for bulk chemicals. 

The influence of Co gamma radiation upon methanol synthesis from carbon monoxide and hydrogen under atmospheric pressure, with ZnO as catalyst, has been studied by Barry and Roberts SO). Various types of zinc oxide are used which are characterized by different stoichiometries. As a consequence considerable differences appear with respect to both catalytic activity and sensitivity to radiation. 

In the water-gas process, hydrogen and carbon monoxide are generated from the reaction between steam and high-temperature coke in a two-step process. In the first step, the coal bed is heated to about 1300 °C with upward blown air. The reactant gas is then switched to steam, creating the syngas and cooling the coal bed. To make optimum use of the heat in the system, steam is blown first upward then downward. When the bed temperature drops to about 900 °C, the steam is stopped and the next cycle is started. The product from the water-gas process can be used for ammonia or methanol synthesis. 

The activity of supported Pt catalysts for methanol synthesis from C0-H2 is considerably enhanced when the metal is supported on oxides which exhibit themselves appreciable activity for MeOH synthesis. Furthermore it is found that the rate of methanol formation on Pt-supported catalyst is increased when Th02, Ce02 were mechanically mixed with the Pt catalyst. Such behaviour is typical for bifunctional catalysts. It has already been reported that Th02, Ce02 adsorb carbon monoxide without dissociation. Such activated CO can be hydrogenated to form a formyl species, the formyl species interacting with lattice oxygen will produce a formate intermediate. 

In this section we describe INS studies of molybdenum trioxide, a precmsor of molybdenum disulfide catalysts ( 7.5), and transition metal oxides which catalyse complete or partial oxidation of hydrocarbons, and copper zinc oxide catalysts, which catalyse methanol synthesis from carbon monoxide and dihydrogen ( 7.3.3). 

The methanol synthesis from carbon monoxide and hydrogen represents an example where diatomic reactants produce a polyatomic product that contains only one bond that was present originally in the reactants. One molecule of C=0 chemisorbs on the catalytic surface via the carbon atom and two molecules of H2 must dissociate before forming three C-H bonds and one 0-H bond. 

The production of mixtures of carbon monoxide and hydrogen from coal or coke was the basis for town gas manufacture from well before the turn of the century, and the processes were adapted to provide appropriate feeds for ammonia and methanol synthesis in Germany and elsewhere. 

Chinchen, G.C., Denny, P.J., Parker, D.G., Spencer, M.S., and Whan, D.A. (1987a) Mechanism of methanol synthesis from carbon dioxide/carbon monoxide/hydrogen mixtures over copper/zinc oxide/alumina catalysts use of carbon-14-labeled reactants. Appl. Catal, 30, 333-338. 

McNeil, M.A., Schack, C.J., and Rinker, R.G. (1989) Methanol synthesis from hydrogen, carbon monoxide and carbon dioxide over a copper oxide/zinc oxide/aliunina catalyst. 11. Development of a phenomenological rate expression. Appl. Catal., 50, 265-285. 

Rozovskii, A.Y., Kagan, Y.B., Lin, G.I., Slivin-skii, E.V., Loktev, S Liberov, L.G., and Bashkirov, A.N. (1975) Mechanism of methanol synthesis from carbon monoxide and hydrogen. Kinet. Katal., 16,810. 

Although these humble origins make interesting historical notes m most cases the large scale preparation of carboxylic acids relies on chemical synthesis Virtually none of the 3 X 10 lb of acetic acid produced m the United States each year is obtained from vinegar Instead most industrial acetic acid comes from the reaction of methanol with carbon monoxide... 

Even though form amide was synthesized as early as 1863 by W. A. Hoffmann from ethyl formate [109-94-4] and ammonia, it only became accessible on a large scale, and thus iadustrially important, after development of high pressure production technology. In the 1990s, form amide is mainly manufactured either by direct synthesis from carbon monoxide and ammonia, or more importandy ia a two-stage process by reaction of methyl formate (from carbon monoxide and methanol) with ammonia. 

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. 

Hydrocarbons from Synthesis Gas and Methanol. Two very important catalytic processes in which hydrocarbons are formed from synthesis gas are the Sasol Eischer-Tropsch process, in which carbon monoxide and hydrogen obtained from coal gasification are converted to gasoline and other products over an iron catalyst, and the Mobil MTG process, which converts methanol to gasoline range hydrocarbons using ZSM-5-type 2eohte catalysts. 

A Belgian patent (178) claims improved ethanol selectivity of over 62%, starting with methanol and synthesis gas and using a cobalt catalyst with a hahde promoter and a tertiary phosphine. At 195°C, and initial carbon monoxide pressure of 7.1 MPa (70 atm) and hydrogen pressure of 7.1 MPa, methanol conversions of 30% were indicated, but the selectivity for acetic acid and methyl acetate, usehil by-products from this reaction, was only 7%. Ruthenium and osmium catalysts (179,180) have also been employed for this reaction. The addition of a bicycHc trialkyl phosphine is claimed to increase methanol conversion from 24% to 89% (181). 

Synthesis gas is an important intermediate. The mixture of carbon monoxide and hydrogen is used for producing methanol. It is also used to synthesize a wide variety of hydrocarbons ranging from gases to naphtha to gas oil using Fischer Tropsch technology. This process may offer an alternative future route for obtaining olefins and chemicals. The hydroformylation reaction (Oxo synthesis) is based on the reaction of synthesis gas with olefins for the production of Oxo aldehydes and alcohols (Chapters 5, 7, and 8). 

Acetic acid is also produced hy the oxidation of acetaldehyde and the oxidation of n-hutane. However, acetic acid from the carhonylation route has an advantage over the other commercial processes because both methanol and carbon monoxide come from synthesis gas, and the process conditions are quite mild. 

About 3 X 109 kg of methanol are produced annually in the United States from synthesis gas, a mixture of carbon monoxide and hydrogen ... 

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