催化裂化油浆中较多链烷烃未裂化原因分析

针对催化裂化油浆中存在较多可裂化而未裂化的饱和烃这一问题，以正十二烷、丁基环己烷、四氢萘、十氢萘等为模型化合物,采用催化裂化实验与分子模拟相结合的方法，对催化裂化过程中链烷烃未充分裂化的原因进行了分析。在链烷烃单独催化裂化反应以及与其它结构烃分子进行混合催化裂化的过程中，链烷烃表现出不同的裂化活性，当链烷烃与强供氢性分子（四氢萘或十氢萘）混合时，链烷烃的裂化受到了明显抑制。在此基础上，结合分子模拟理论计算结果，提出了分子间负氢离子转移是导致催化裂化过程中链烷烃未充分裂化的主要原因之一。

KEY REASONS FOR UNCRACKED ALKANE IN FCC SLURRY

N-dodecane, butyl-cyclohexane, tetralin, decalin, and their mixtures were used as the model compounds and the combined techniques of FCC test and molecular simulation were adopted to study the reasons for a lot of uncracked chain alkane existing in FCC slurry. It is found that alkanes have different cracking performance in their single state or in a mixed one. When the alkane is mixed with strong hydrogen-donating molecules, like tetralin or decalin, the conversion of alkane is significantly depressed. Based on the results of experiment and molecule simulation, and reaction chemistry, a conclusion can be drawn that the hydride transfer between hydrocarbon molecules is the main reason that results in a lot of saturated, uncracked chain alkane in FCC slurry.