Mechanism of Coal Liquefaction - Reaction of Model Compounds

以煤为模型化合物，在稳定镍或合成黄铁矿的催化下，在高压氢气条件下进行了苯、苯醚和二苯的加氢反应，阐明了煤液化的反应机理。以萘、四氢化萘和十氢化萘为溶剂，在250 ~ 500℃的温度下，在3 ~ 10mpa的氢气条件下对0 ~ 60苯胺进行反应。以稳定镍为催化剂，加氢能力强，在250 ~ 350℃的温度下，对苯基苯醚或二苄基苯环进行加氢反应。苯基苯醚在250℃时C-0键几乎完全裂解，生成苯酚和甲苯。苯酚很容易氢化成环己醇。在高于370℃的温度下，环己烷和苯因脱羟基和脱氢作用而增加。随着氢气压力的增加，加氢和脱羟基作用加快，气体的生成和冷凝减少。在合成黄铁矿作催化剂的情况下，苯基苯醚的加氢能力弱，产生的加氢产物很少。以十氢化萘为溶剂的缩合产物较多，如二苄酚或三苄酚。这些缩合产物在反应初期产生，然后随着反应的进行分解为苯酚、苯酚和甲苯。在低于450℃的温度下，Djbenzyl与合成的黄铁矿几乎没有反应，这与稳定的镍不同。

Benzyl phenyl ether and dibenzyl as model compounds of coal were hydrogenolyzed under high pressure of hydrogen in the presence of stabilized nickel or synthetic pyrite as the catalyst to elucidate the reaction mechanism of coal liquefaction. The reactions were carried out at 250-500ﾟC, under 3-10MPa of hydrogen for 0-60inin with naphthalene, tetralin and decalin as the solvent.In the case of stabilized nickel used as catalyst, which has strong ability in hydrogenation, the benzene rings of benzyl phenyl ether or dibenzyl were hydrogenated at 250-350ﾟC. Benzyl phenyl ether was split at C-0 bond almost completely at 250ﾟC and converted to phenol and toluene. Phenol was easily hydrogenated to cyclohexanol. At the higher temperature than 370ﾟC, cyclohexane and benzene increased due to dehydroxylation and dehydrogenation. With the increase in hydrogen pressure, hydrogenation and dehydroxylation accelated and gas formation and condensation were reduced.In the case of the synthetic pyrite as catalyst, benzyl phenyl ether produced little the hydrogenated products because of the weak hydrogenation ability. The larger amount of the condensed products such as dibenzyl phenol or tribenzyl phenol were produced in the reaction with decalin as solvent. These condensed products were produced in the early stage of reaction and then decomposed to benzyl phenol, phenol and toluene as the reaction proceeded. Djbenzyl reacted little at the lower temperature than 450ﾟC with the synthetic pyrite, that is difference from the stabilized nickel.