“二次白泥”合成DOTP的研究

Study on the Synthesis of DOTP by "Secondary White Mud"

“二次白泥”是以碱减量白泥为原料生产DOTP过程中,和废水酸析产生的固体物料压滤得到的产物,通过红外光谱以及合成反应实验,确定了二次白泥的主要组成为乙二醇二对羧基苯甲酸酯。以“二次白泥”为原料,通过酯化、醇解反应合成DOTP,考察了醇酸摩尔比、催化剂加入量以及反应终点温度对反应时间和产品收率的影响,实验表明醇酸摩尔比为6.0、催化剂加入量为酸量的0.5%、反应终点温度为225~230℃,反应7.5 h即可合格,收率达93%,产品纯度达99.07%,各项指标均达到电缆料使用标准。

"Secondary white mud"was produced by acidification of wastewater from DOTP synthesis process using alkali weight-reduction white mud as material.The main composition of secondary white mud was proved to be ethylene glycol terephthalate(1∶2)by IR spectroscopy and synthetic reaction experiments.We adopted a new method of DOTP synthesize from"secondary white mud"by esterification and alcoholysis reaction.The effects of molar ratio of alcohol to acid,catalyst amount and reaction temperature on reaction time and product yield were investigated.Experimental results showed that the DOTP yield was 93%(99.07%purity)under the optimal conditions of alcohol/acid ratio 6.0,catalyst amount constituting 0.5%that of acid,final reaction temperature 225℃to 230℃and reaction time 7.5h.All of performance indexes of DOTP product reached the cable material use standard.