含2-乙基己酸的多元醇酯对皂化值测定的影响  

Influence of Polyol Esters Containing 2-Ethylhexanoic Acid on Determination of Saponification Number

作　　者：李进[1] 彭立[1] 魏斌斌[1] LI Jin;PENG Li;WEI Bin-bin(PetroChina Lanzhou Lubricating Oil R&D Center,Lanzhou,Gansu 730060,China)

机构地区：[1]中国石油兰州润滑油研究开发中心,甘肃兰州730060

出　　处：《润滑油》2022年第5期48-50,共3页Lubricating Oil

摘　　要：采用GB/T 8021-2003《石油产品皂化值测定法》测定合成酯皂化值,是反映合成酯纯度以及分子量的重要指标。对大部分合成酯,方法规定30 min的皂化时间可满足测量要求,皂化值接近理论值。对含2-乙基己酸的多元醇酯,30 min的皂化时间,皂化值测量结果偏低,不能正确反映该类合成酯的皂化值。通过解析皂化值偏低的季戊四醇酯组成结构,并合成相应合成酯,将皂化反应时间由30 min延长至120 min,验证含2-乙基己酸多元醇酯皂化测量值偏低,是由于含2-乙基己酸的酯基团降低了皂化反应速度,从而导致该类酯在30 min皂化不完全。The saponification number of polyol esters,an important indicator reflecting the purity and molecular weight of synthetic esters,is determined in accordance with the Petroleum Products-Determination of Saponification Number(GB/T 8021-2003).For most synthetic esters,the saponification time specified in the determination method,i.e.30 min,can meet the measurement requirements,and the measured results are close to the theoretical saponification number.For a polyol ester containing 2-ethylhexanoic acid,the measured result is low for a saponification time of 30 min,which cannot properly reflect the saponification number of the synthetic ester.By analyzing the composition structure of the pentaerythritol ester with low saponification number and synthesizing the corresponding synthetic ester,the saponification time was extended from 30 min to 120 min.It was verified that the saponification rate was slowed down due to the existence of ester group containing 2-ethylhexanoic acid,which led to incomplete saponification of the ester within 30 min.As a result,the saponification number of polyol ester containing 2-ethylhexanoic acid was low.

关 键 词：合成酯 皂化值 2-乙基己酸 分子量 

分 类 号：TE626.4[石油与天然气工程—油气加工工程]