Coal hydrogenation recent development

Coal hydrogenation to produce motor fuels is not as yet economical, even after allowing credit for various by-product chemicals such as phencd, cresols, xylenols, toluene, xylenes, naphthalene, and liquified hydrocarbon gases. The immediate future of coal hydrogenation probably depends on the recent developments such as those of Union Carbide Chemicals Com-paiQT toward the production of hi yields of chemicals, although a large proportion of these consists of complex structures that are not well-known. 

Coprocessing (Chapters 18 and 19), a recent development for coal liquefaction technology, involves the production of liquids from a mixture of coal and heavy petroleum residue, with the residual oil providing all or most of the hydrogen needed for the conversion process. Once produced, the coal-derived liquid can be refined by sulfur mineral matter (ash) ranoval before use. 

A comprehensive analysis dealing with the various asymptotic cases of gas-liquid mass transfer in series with various particle conversion mechanisms in the bulk has been presented recently by Doraiswamy and Sharma [l] Such a model has been successfully applied to oxydesulfurization of coal [l5l]. As far as we know, no analysis has been presented as yet for the case where the particles are small with respect to the gas-liquid film for mass transfer, and consequently may enhance the gas-liquid mass transfer process. According to our experience it plays a role in a new process that we recently developed for the concentration of hydrogen from lean gas mixtures with a slurry containing finely hydridable metal part-Icles [16,139,152-154], (Fig. 23). 

Coal analysis has, by convention, involved the use of wet analysis or the use of typical laboratory bench-scale apparatus. This trend continues and may continue for another decade or two. But the introduction of microprocessors and microcomputers in recent years has led to the development of a new generation of instruments for coal analysis as well as the necessary calibration of such instruments (ASTM D-5373). In particular, automated instrumentation has been introduced that can determine moisture, ash, volatile matter, carbon, hydrogen, nitrogen, sulfur, oxygen, and ash fusion temperatures in a fraction of the time required to complete most standard laboratory bench procedures. 

Dyrkacz and his coworkers have recently described a new procedure for the separation of coals into macerals (14). The macerals can be obtained in pure form, but only in limited quantity. Inasmuch as many of the methods used for the study of coal require relatively large amounts of material, we have undertaken new work on the development of small scale reactions for the accurate determination of the differences in chemical reactivity of macerals. The hydrogen transfer reactions are discussed in this report. Preliminary work revealed that very reproducible results could be obtained when 25 mg of a representative maceral was used as a catalyst for the hydrogen exchange reaction between tetra-... 

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