Coal-based synthetics, sulfur

POTENTIAL SULFUR FROM COAL-BASED SYNTHETICS... 

Gasification technologies offer the potential of clean and efficient energy. The technologies enable the production of synthetic gas from low or negative-value carbon-based feedstocks such as coal, petroleum coke, high sulfur fuel oil, materials that would otherwise be disposed as waste, and biomass. The gas can be used in place of natural gas to generate electricity, or as a basic raw material to produce chemicals and liquid fuels. 

Phenol was prepared before World War I through the distillation of coal tar. The first synthetic process involved the sulfonation of benzene followed by desulfonation with a base. In this process, benzene sulfonic acid is prepared from the reaction of benzene and sulfuric acid ... 

The investments shown are estimated for an urban midcontinent location. As mentioned above, the estimate for the boiler plant is based on coal-fired burners with attendant stack gas sulfur dioxide (SC ) removal facilities. As indicated on Table XX, no allowance is made for (a) coal resource costs, (b) coal mining or handling, (c) conversion of coal to oil by SRC-II process, (d) SRC-II oil transportation to, or (e) refined product distribution and transportation from the refinery. These additional costs are not required to evaluate refinery processing costs. However, they should be included if it is desired to determine the overall economics of a specific synthetic crude oil refining project. 

Quinoline was discovered in coal tar by Friedlieb Ferdinand Runge in 1834 it is present in concentrations of approximately 0.3%. Quinoline is recovered by extraction with sulfuric acid from the methylnaphthalene fraction of coal tar, followed by springing with ammonia and rectification of the crude base mixture. Quinoline can be synthesized by the Skraup method, by the reaction of aniline with glycerol (or acrolein produced from glycerol) and catalytic gas-phase reaction of aniline with acetaldehyde. Since the supply of the tar-derived material has been adequate for a long time, synthetic production is not warrented. 

Coal ash corrosion is a widespread problem for superheater and reheater tubes in coal fired power plants that bum high-sulfur coals. The accelerated corrosion is caused by liquid sulfates on the surface of the metal beneath an over-lying ash deposit. Coal ash corrosion is very severe between 540 and 740°C (1000°F and 1364°F) because of the formation of molten alkali iron-trisulfate. Considerable work has been done to predict corrosion rates based on the nature of the coal (its sulfur and ash content). This was accomplished by the exposure of various alloys to synthetic ash mixtures and synthetic flue gases. The corrosion rates of various alloys were repotted in the form of iso-corrosion curves for various sulfur dioxide, alkali sulfiite, and temperature combinations. An equation was developed to predict corrosion rates for selected alloys from details of the nature of ash by analyzing deposits removed from steam generator tubes and from test probes installed in a boiler [33]. Then laboratory tests were conducted using coupons of various tdloys coated with synthetic coal ash that was exposed to simulated combustion gas atmospheres. 

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