皂化法制备硬脂酸钇及其动力学研究  

Preparation and Kinetic Study of Yttrium Stearate by Saponifying Reaction Method

作　　者：蒋柏泉[1] 陈常青[2] 叶志强[1] 刘贤湘 

机构地区：[1]南昌大学环境与化学工程学院,江西南昌330029 [2]江西华能瑞金电厂,江西赣州341000

出　　处：《稀有金属》2007年第3期341-345,共5页Chinese Journal of Rare Metals

基　　金：江西省科技攻关项目(2005)

摘　　要：采用皂化法制备了PVC热稳定剂-硬脂酸钇,并进行了动力学研究。采用单因素实验方法对反应时间、反应温度、盐碱比、氢氧化钠浓度等因素分别对硝酸钇/氢氧化钠盐碱反应和氢氧化钇/硬脂酸皂化反应的稀土转化率的影响进行了考察,并确定了最优工艺条件,建立了动力学模型。实验结果表明,采用改进的新工艺,稀土转化率高达99.50%以上,硬脂酸钇的熔点为118℃。经实验验证,第一阶段硝酸钇/氢氧化钠盐碱反应为二级反应,动力学方程为-dcA/dt=8.56cA2。第二阶段近似看作氢氧化钇/硬脂酸的皂化反应,符合二级反应特征,动力学方程为-dcA/dt=1666cA2。采用称重法测定稀土转化率比化学法简单、快速。The study on technical process and kinetics of PVC heat steadilizer yttrium stearate by saponifying method was carried out. The effects of reaction time.reaction temperature, salt//alkali ratio and NaOH concentration on yttrium nitrate/sodium hydroxide reaction and yttrium hydroxide/stearic acid reaction were investigated with single factor method respectively. The optimal technical conditions for the two reactions were determined and the kinetic models were established. The experimental results showed that the conversion of rare earths reached more than 99.50% and the melting point of the yttrium stearate was 118 ℃ when the partly improved technique was used. The experiments proved that the first stage reaction-yttrium nitrate /sodium hydroxide reaction was a second order reaction and its kinetic equation was - dcA/dt = 8.56 cA^2. The second stage reaction was approximately seen as single yttrium hydroxide/stearic acid reaction to carry out kinetics research, which was in accordance with the characteristics of second order reaction and the kinetic equation was expressed as - dcA/dt = 1666 cA^2. The weight method was simpler and faster than chemical method for measuring the conversion of rare earths.

关 键 词：PVC热稳定剂 钇 硬脂酸钇 皂化反应 稀土 

分 类 号：TQ320[化学工程—合成树脂塑料工业]