焦化蜡油中芳香分的催化裂化特性及其对饱和分裂化性能的阻滞作用

采用糠醛抽提,从焦化蜡油(CGO)中抽提分离出芳香分,考察芳香分的催化裂化反应特性及其对饱和分催化裂化反应性能的阻滞作用。结果表明:糠醛对CGO中的芳烃具有较好的抽提效果,减弱了稠环芳烃对饱和烃的竞争吸附和对其反应的阻滞作用,使CGO抽余油的催化裂化性能明显优于CGO原料油,转化率提高了15.3个百分点,而芳烃抽出油的转化率比CGO原料油降低了16.1个百分点;剂油比对提高芳烃抽出油转化率和目的产品收率的效果最为显著,质量空速的效果次之,而反应温度的效果最差;芳烃抽出油不仅本身很难催化裂化,而且还阻碍了饱和分的有效催化转化,从而使原料的转化率下降,目的产品收率降低,焦化蜡油中的多环或稠环芳烃是制约其有效催化转化的关键因素之一。

Catalytic cracking performance of aromatics in coker gas oil and retardation effect on saturates

Aromatics were separated from coker gas oil (CGO) using the furfural extraction. The catalytic cracking performance of aromatics and the retardation effect on saturates were investigated. The results show that the furfural has good extraction effect on aromatic hydrocarbons from CGO, which weakens the competitive adsorption and retardation effect of polycyclic aromatics on the saturated hydrocarbons. As a result, the raffinate oil has 15.3% higher conversion than CGO, while the extracted oil has 16.1% lower conversion than CGO. Increasing the ratio of catalyst to oil can significantly enhance the conversion of extracted oil and yields of desired products. And the effect of mass space velocity is less. The influence of reaction temperature is the least compared to the above two factors. The extracted oil is not only difficult to catalytic cracking, but also hinders the effective catalytic cracking of saturates, which results in the declined feedstock conversion and reduces desired products yield. Consequently, the polycyclic/fused aromatics are one of the key factors restricting the effective catalytic cracking of CGO.