Gasification continued reactions

After World War II, direct liquefaction of coal became uneconomical as the use of lower-cost petroleum products became more widespread. However, the German process of indirect coal liquefaction, the Fischer-Tropsch process, continued to hold some interest. The Fischer-Tropsch process first involved production of a carbon monoxide and hydrogen-rich synthesis gas by the controlled gasification of coal followed by a catalytic reaction process to yield a valuable mixture of hydrocarbon products. Simplified Fischer-Tropsch reactions are shown by the following equations ... 

Heats of reaction (AHt) of some gasification reactions are listed in Table 4.4. Some of the reactions are endothermic (i.e., require heat in order to continuously proceed), as indicated by the positive values of AHt in Table 4.4. The heat required for these endothermic reactions is supplied by the complete or partial oxidation of a small proportion of the coal volatiles and/or char in 02 or in air. 

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