Coal-derived Synthesis Gas

16 Chem.Br., 1983, 19, 896 here it is reported that Tennessee Eastman is commissioning a plant for the production of acetic anhydride from coal which uses a Texaco entrained-bed gasifier to produce syngas. 

Sudbury, B. J. Koch, and H. Yoon, Proc. 1st Int. Gas Res. Conf., 1980, p. 687 this conference proceedings also describes a number of other coal gasification processes. 

Boegner, R. Vangala, and T. K. Subramaniam, Proc. 8th. Ann. Conf. Coal. Gasif. Liquef. Convers. Electr., (1981), 1982, p. 141. 

Cornils, P. Rufrecht and R. Durrfeld (Ruhrchemie AG), Proc. 16th. Intersoc. Energy Convers. Eng. Conf., 1981, Vol. 2, p. 1050. 

Woodward, Hydrocarbon Process., Jan. 1977 I.C.I. Catalyst Tech. Paper, No. 4. 

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Sasol produces synthetic fuels and chemicals from coal-derived synthesis gas. Two significant variations of this technology have been commercialized, and new process variations are continually under development. Sasol One used both the fixed-bed (Arge) process, operated at about 240°C, as weU as a circulating fluidized-bed (Synthol) system operating at 340°C. Each ET reactor type has a characteristic product distribution that includes coproducts isolated for use in the chemical industry. Paraffin wax is one of the principal coproducts of the low temperature Arge process. Alcohols, ketones, and lower paraffins are among the valuable coproducts obtained from the Synthol process. 

A chemistry based on the conversion of synthesis gas has been developed and appHed extensively in South Africa to the production of Hquid fuels and many other products. A small-scale production is used in the manufacture of photographic film materials from coal-derived synthesis gas in the Eastman Kodak plant in Kingsport, Tennessee. However, the principal production of chemicals from coal involves the by-products of coke manufacturing. 

The compositions of reactant flow are Usted in Table 1. The composition A is for the basic reaction test under water-free reaction condition, the composition B is for the reaction test under the influence of water, and the composition C is for the reaction test with the coal-derived synthesis gas. 

Figure 6 and Figure 7 show the reaction properties for the 10% and 18% water contents over V2O5 under the environment of coal-derived synthesis gas. The reaction property of V2O5 was enhanced by the decrease of reactant reducing power, controlled by the increase of water content. 

From these results, it was believed that the decrease of the V2O5 reoxidation property, caused by the increase of the reducing power, leaded to the deterioration of the activity of V2O5 catalyst in the selective oxidation of H2S under the environment of coal-derived synthesis gas. And the decreased reoxidation property of the V2O5 was enhanced by increasing oxygen and/or water content. 

Figure 6. Reaction property of V2O5 under the environment of coal-derived synthesis gas with 10% water content at 175 °C.

The direct carbonylation of methanol yielding acetic acid, the Monsanto process, represents the best route for acetic acid. Carbonylation of methyl acetate, obtained from methanol and acetic acid, gives acetic anhydride, a technology commercialized by Tennessee Eastman (22). It is noteworthy that this process is based on coal derived synthesis gas to give as the final product cellulose acetate. A combination of Monsanto and Tennessee Eastman technology opens the door for the combined synthesis of acetic acid and acetic anhydride. 

Conven coal-derived synthesis gas to liquid or gaseous fuels. 

Sulfur poisoning is a key problem in hydrocarbon synthesis from coal-derived synthesis gas. The most important hydrocarbon synthesis reactions include methanation, Fischer-Tropsch synthesis, and methanol synthesis, which occur typically on nickel, iron, or cobalt, and ZnO-Cu catalysts, respectively. Madon and Shaw (2) reviewed much of the early work dealing with effects of sulfur in Fischer-Tropsch synthesis. Only the most important conclusions of their review will be summarized here. 

Clearly, the number of chemicals produced from coal-derived synthesis gas can expand as new technologies are developed and favorable economics exist. The most likely such chemicals are those for which processes have been demonstrated but which presently are uneconomic. Relatively small improvements in technology, shifts in feedstock availability and/or... 

Gardner et al. reported that H2S catalytic partial oxidation technology with an AC catalyst is a promising method for the removal of H2S from fuel cell hydrocarbon feedstocks.206 Three different fuel cell feedstocks were considered for analysis sour natural gas, sour effluent from a liquid middle distillate fuel processor, and a Texaco 02-blown coal-derived synthesis gas. Their experimental results indicate that H2S concentration can be removed down to the part per million level in these plants. Additionally, a power-law rate expression was developed and reaction kinetics compared with prior literature. The activation energy for this reaction was determined to be 34.4 kJ/g mol with the reaction being first order in H2S and 0.3 order in 02. 

Hydrogen from coal program research, development, and demonstration plan. , issued by DOE, 26 September, 2005, www.fe.doe.gov Syntroleum press release Syntroleum initiating testing program with coal-derived synthesis gas , 29 November, 2005. 

Eastman Chemical Co. and Air Products and Chemicals, Inc. Removal of Trace Contaminants from Coal-Derived Synthesis Gas Topical Report, Contract DE-FC22-92PC90543, March 2003. 

First era of cobalt catalyst Commercial developments in Germany and other eountries, with coal derived synthesis gas. 

J. Li, Z. Hongwei, R. Razzaq, C. Li, L. Zengxi, Effect of structural and lattice oxygen changes on the properties of CuO/Ce02 catalysts for high-temperature water-gas shift of H2-rich coal-derived synthesis gas, Z. Phys. Chem. 227 (2013) 371—387. 

Future work will include testing some of the new membranes that have shown high ideal separation factors for helium over sulfur hexafluoride with hydrogen to confirm that our results also apply to hydrogen. Also, efforts will be made to test the best membranes at temperatures approaching 600°C to empirically determine how much the permeance and separation factors increase with increasing temperature. Finally, the membranes need to be evaluated under simulated coal-derived synthesis gas conditions to determine their actual separation performance and long-term stability. 

Sasol produces Cj-Cg a-olefins from coal-derived synthesis gas processing followed by olefin extraction by fractionation. Sasol has announced that they will extend the process to also recover higher carbon number a-olefins. The extraction process has the ability to further recover Cg a-oleflns and there is the potential to also produce Cjj-Cjg a-olefins by the same process. 

Among the alternative raw materials most liely to be used on a large scale> synthesis gas, its main derivative, methanol, and methane, receive the larger attention[9,10]. Apart from methanol production, synthesis gas has various industrial application, among which the carbonylation of methanol to acetic acid, the hydroformylation process, and, introduced very recently, the production of acetic anhydride. This last process is particularly interesting, because it is based on coal derived synthesis gas. And the incidence of coal derived syngas on the overall production, presently lower than 5%, will increase in the future with the prices of crude oil. 

Tian H, Simonyi T, Poston J, Siriwardane R. Effect of hydrogen sulfide on chemical looping combustion of coal-derived synthesis gas over bentonite-supported metal-oxide oxygen carriers. Ind Eng Chem Res 2009 48 8418. 

Houdry Catalytic cracking of oil in USA Fischer-Tropsch plants in Germany produce synthetic fuels from coal-derived synthesis gas... 

Klasson, K.T., et al., 1993a. Biological conversion of coal and coal-derived synthesis gas. Fuel 72 (12), 1673-1678. 

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