摘要
实验分析发现 ,RFCC稳定汽油SRSH滴定电位有两个明显的突跃 ,其中第一个突跃电位在-1 0 0～ 1 0 0mV之间 ,第二个突跃电位约为 1 0 0～ 3 0 0mV。精制汽油的滴定初始电位 >0mV ,其滴定曲线只有一个明显的突跃 ,其滴定曲线变化规律及突跃电位与稳定汽油的第二突跃相同。通过大量的实验数据分析及在与文献数据比较的基础上 ,根据RFCC汽油中硫醇的特性及滴定曲线规律 ,将其分为两种类型。用电位滴定法可分别测定二类硫醇的硫醇硫含量 ,从而预测汽油中硫醇的组成及分布。第一类硫醇主要是低级硫醇及苯硫酚化合物 ,经碱洗及固定床脱臭基本可被脱除 ;第二类硫醇主要是C5以上异构硫醇 ,碱洗及固定床脱臭难以脱除此类硫醇。稳定汽油中的第二类硫醇硫含量决定了其精制汽油的硫醇硫含量。
The experiment analysis has found that titratic potentals of sulphur-mercaptans(S-mercaptans) in RFCC's stable gasoline have two obvious sudden changes: the first sudden change of potentials is in the range of -100～100 mV,the second is about in the range of 100～300 mV. The original titratic potential of the refined gasoline is larger than 0 mV,and its titrative curve has only one sudden change. The varying law of the titrative curve and sudden change of potentials of the refined gasoline are like those of stable gasoline. By comparing a great number of experiment data with the data in literature, the mercaptans in RFCC gasoline can be divide into two types according to its characteristic and the titrative curve law, S-mercaptan content of tow type mercaptans may be respectively determined, so that the composition and distribution of mercaptans in gasoline can be forecasted. The first of these mercaptans is mainly the elementary mercaptan or thiophennol, and these may be swept by basic-washing or by the Merox method; the second type of mercaptan is mainly large molecular (≥C 5) isoconstructive mercaptans, and they are difficult to be cleared out. The second type of the S-mercaptan content in the stable gasoline decides the S-mercaptan content in the refined gasoline.
出处
《石油化工高等学校学报》
EI
CAS
2001年第1期29-32,共4页
Journal of Petrochemical Universities
关键词
电位滴定法
汽油
硫醇
预测
组成
分布
Potentiometric titrate
Gasoline
Mercaptan classify
