Synthesis gas derivatives

Volume 1. Synthesis-Gas Derivatives and Major Hydrocarbons. Volume 2. Major Oxygenated, Chlorinated and Nitrated Derivatives. 

Of all the oxygenates, methyl-t-butyl ether (MTBE) is attractive for a variety of technical reasons. It has a low vapor pressure, can be blended with other fuels without phase separation, and has the desirable octane characteristics. If oxygenates achieve recognition as vehicle fuels, the biggest contributor will probably be methanol, the production of which is mostly from synthesis gas derived from methane. 

The rapidly growing world concern over future oil supplies has led to considerable research activity into the use of synthesis gas or synthesis gas-derived molecules, such as methanol, as future feedstock materials for... 

This work represents part of a program designed to identify Fischer-Tropsch (FT) catalysts for the processing of H2 rich synthesis gas derived from natural gas. Current advanced gas processes are generally a combination of partial oxidation and steam reforming, resulting in H2 C0 ratios of about 1.5-2.3. 

The recent interest in chemical production is based on a higher return expected for chemical [uoducts versus fuels. For example, biomass gasification can be used to produce a synthesis gas of hydrogen and carbon monoxide. This gas can be used in catalytic synthesis of a range of chemicals, from methanol and formaldehyde to higher hydrocarbons, in the same way that synthesis gas derived from natural gas can be used. However, by breaking down the biomass to the basic building blocks all product differentiation relative to fossil fuels is lost. 

Chauvel, A. Lefebvre, G. Petrochemical Pricess. Vol. 1—Synthesis-Gas Derivatives and Major Hydrocarbons, 2nd Ed. Editions Technip Paris, 1985 (in French), 1989 (in English). 

Substitute Natural Cas iSNG) Methane produced from synthesis gas derived from steam reforming naphthas, coal, or biomass. 

In chemical industries, most pure hydrogen applications require amounts that are small compared to those involved in other synthesis gas derivatives. Sometimes, the amount is too small to consider steam reforming of methane. Obviously, there are other sources for pure hydrogen especially in small amounts. Depending upon the size of the business and the supportive infrastructure around the industry, the source for pure hydrogen will be determined. 

Figure 2 shows the products obtained in a scheme in which direct upgrading of the wood pyrolysis liquids over ZSM-5 occurs in parallel with upgrading of methanol obtained from synthesis gas derived from gasification of the pyrolysis char. In Figure 3, the methanol is mixed with the pyrolysis liquids prior to co-processing over ZSM-5. Approximately 40 lbs. of methanol per 100 lbs. of dry wood feed is potentially available from the char and pyrolysis gas products. 

The following types of processes may be taken into account for purifying and conditioning methanol synthesis gas derived from coal ... 

Commercialization of the novel syngas-to-alcohol-ester fuels (7), syngas acetic acid (125), and SFA processes (96,97) described in this review will hinge primarily upon projected 1990 s economics, particularly the relative feedstock values of petroleum and natural products, versus synthesis gas derived from coal or natural gas. 

Chauvel, A. and Lefebvre, G. (1989) Petrochemical Processes 1. Synthesis-Gas Derivatives and Major Hydrocarbons, Petrochemical Processes 2. Major Oxygenated, Chlorinated and Nitrated Derivatives, Editions Technip, Paris. 

Entrained-flow gasifiers are attractive for synthesis gas derivatives, such as methanol, due to their high yield of synthesis gas with essentially no production of methane or other hydrocarbon products. In addition, the slurry feed Texaco process ensures reliable high-pressure operation and a relatively high Hj/CO ratio of synthesis gas. 

The Selexol process has found a very wide range of applications. It was originally used to remove CO2 from an ammonia plant in Nebraska, followed soon after by H2S and CO2 removal from natural gas in the U.S. and in Europe. Other applications include desulfurization and CO2 removal from synthesis gas derived from the partial oxidation of heavy petroleum stocks and from coal gasification. Natural gas treating applications include several, where in addition to production of pipeline specification gas, a relatively pure stream of carbon dioxide is produced for reinjection into oil formations, so-called enhanced oil recovery or EOR. A relatively new use for the process dating back to 1979 is the purification of landfill gas drawn from the biological degradation of municipal waste in sanitary landfills. This application is characterized by the occurrence of chlorinated and aromatic hydrocarbons as impurities in the landfill gas. 

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