高酸原油自催化酯化反应的原因探讨

STUDY ON THE CAUSE OF AUTOCATALYTIC ESTERIFICATION OF HIGH ACID CRUDES

采用10种国内外高酸原油在无外加催化剂的条件下进行酯化降酸试验,分析原油性质与酯化降酸率之间的关系,探讨高酸原油自催化酯化反应的原因。结果表明,高酸原油自催化酯化降酸反应的主要原因是原油中以羧酸盐形式存在的钙充当了酯化催化剂,钙含量为140～300μg/g时催化酯化降酸效果较好。鉴于原油加工过程对钙含量的要求,高酸原油并不适于采用自催化直接酯化降酸。

The esterification experiments for reducing acid content of high acid crude oils were carried out without the presence of additional catalyst. Ten domestic and imported high acid crudes were involved in discussing the relationship between crude oil properties and the acid removal rate for further study the cause of autocatalytic esterification of high acid crudes. Test results showed that when the calcium contents of crude oils were in the range of 140--300 μg/g, good acid removal rates were observed,which indicated that calcium naphthenate in high acid crudes might act as catalyst to catalyze the esterification of high acid crudes. However, it is unsuitable to adopt the autocatalytic esterification for reducing acid content of high acid crudes due to the limitation of calcium content in crude oil processing.