石脑油制低碳烯烃的影响因素研究

Factors of catalytic cracking of naphtha to light olefins

采用自制催化剂,通过实验对比了石脑油热裂解和催化裂解反应的特征,考察了反应温度、反应时间、重时空速和石脑油分压等反应条件对石脑油催化裂解反应产物分布和产率的影响。实验结果表明,在较高反应温度下,石脑油的热裂解反应和催化裂解反应同时存在,且催化裂解反应相对于热裂解反应具有明显的优势;温度越高,热裂解产物越多,而催化裂解产物先增加后减少;增加催化裂解时间和热裂解时间之比能明显提高低碳烯烃的产率;降低重时空速能提高石脑油的转化率;而降低石脑油分压对多产低碳烯烃非常有利。

The reaction characteristics of thermal cracking and catalytic cracking of naphtha were compared by using self-made catalysts.The influence of reaction conditions,such as temperature,time,WHSV and partial pressure of naphtha,on product distribution and yield in the catalytic cracking of naphtha was also investigated.The experimental results showed that thermal cracking and catalytic cracking of naphtha occurred simultaneously under a high reaction temperature,and catalytic cracking showed obvious advantages over thermal cracking.Specifically,there are more products of thermal cracking under a higher temperature.The products of catalytic cracking increased first and then decreased with increasing temperature.Increasing the ratio of catalytic cracking time to thermal cracking time could increase the yield of the light olefins.Decreasing WHSV could improve the conversion of naphtha.Reducing the partial pressure of naphtha facilitated increasing the yield of light olefins.