加氢裂化尾油窄馏分的催化裂化转化规律研究

CATALYTIC CRACKING PERFORMANCE OF NARROW FRACTIONS OF HYDROCRACKING TAIL OIL

将中东减压蜡油的加氢裂化尾油分为4个沸程范围不同的窄馏分,在固定流化床装置上考察了其催化裂化反应性能,采用GC/MS等方法对原料和裂化产物的烃类组成进行了分析。结果表明,4个窄馏分中饱和烃质量分数均高于98.0%,随着馏分变重,窄馏分中的链烷烃含量增大,环烷烃含量减小,并且链烷烃和各族环烷烃均向高碳数方向移动。4个窄馏分均易于裂化,干气和焦炭产率低,液化气和汽油收率高。在相同的催化裂化条件下,随着馏分变重,其可裂化性能增强,干气和焦炭产率降低,液化气收率增加,汽油收率增加但辛烷值略有降低,柴油和重油收率均降低。

The hydrocracking tail oil of vacuum gas oil from Middle Eastern crude was cut into four narrow fractions. The catalytic cracking performance of fractions was tested in an advanced catalyst evaluation device （ACE）. The hydrocarbon compositions of fractions and cracked products were analyzed by GC-MS. The results show that the content of saturates in the four fractions are all above 98.0%, and the content of paraffins increases while the content of naphthenes decreases with the cuts getting heavier, simultaneously, the paraffin and naphthene compounds shift toward the direction of high carbon numbers. The four fractions are prone to be cracked with high yields of LPG and gasoline and low yields of dry gas and coke. Under the same reaction conditions, as the fractions moving in the direction of higher boiling point, the cracking ability increases, the yield of dry gas and coke decreases, the yield of LPG increases, the yield of gasoline increases with a slight loss in octane number, and the yield of diesel and heavy oil decreases.