YN-1镍系裂解C_(9)重馏分一段加氢催化剂的工业应用

Industrial Application of YN-1 Nickel First-stage Hydrogenation Catalyst for Cracking C_(9) Heavy Fraction

裂解C_(9)重馏分是以石脑油为裂解原料的乙烯装置的主要副产物之一,约占乙烯产量的10%~20%。裂解C_(9)重馏分组成极其复杂,含有许多带有双键的活性组分,溴价、碘值及胶质较高,给后续利用带来困难。裂解C_(9)重馏分通过两段加氢,可以转化为低溴价、低硫的碳九加氢产品。简要分析了裂解C_(9)重馏分加氢反应的热力学,其中苯乙烯和茚的加氢反应均为较强的放热和熵增反应,在热力学上是有利的。考察了反应温度、压力及原料性质变化对产品质量的影响。结果表明,YN-1催化剂对不同的裂解原料,不但具有良好的低温加氢活性、选择性,同时具有很好的稳定性,催化剂床层未出现飞温现象,催化剂能够适应超过90℃的反应温升,并且催化剂表现出容胶量大的优点,满足工业应用需要。一段加氢后,可以为二段加氢提供合格原料。目前一段加氢催化剂使用寿命达到8年。

Cracking C_(9) heavy fraction is one of the main by-products of ethylene plant with naphtha as the raw material,accounting for about 10% to 20% of the ethylene output.The composition of the cracking C_(9) heavy fraction is extremely complex.It contains many active components with double bonds,and has high bromine value,iodine value and colloid,which brings difficulties to the subsequent utilization.The cracking C_(9) heavy fraction can be converted to C_(9) hydrogenated products with low bromine value and low sulfur by two-stage hydrogenation.The thermodynamics of hydrogenation of C_(9) heavy fraction were briefly analyzed,and both the hydrogenation reactions of styrene and indene were strong exothermic and entropy increasing reactions,which were thermodynamically favorable.The influence of reaction temperature,pressure and feed properties on product quality was investigated.The results show that for different pyrolysis raw materials,catalyst YN-1 has good hydrogenation activity and selectivity at low temperature and good stability.There is no temperature run-away in catalyst bed,the catalysts can adapt to a reaction temperature rise of more than 90 ℃,and the catalysts show the advantage of large amount of sol,meeting the needs of industrial application.The first-stage hydrogenation can provide qualified raw materials for the second-stage hydrogenation.Currently the service life of first-stage hydrogenation catalyst is up to 8 years.