文献类型：期刊文献

中文题名：反应-萃取-结晶过程制备碳酸钙的晶型转变与结晶机理

英文题名：Polymorph transformation and formation mechanism of calcium carbonate during reactive extraction-crystallization process

作者：李云钊[1];宋兴福[1];孙玉柱[1];孙泽[1];于建国[1]

机构：[1]华东理工大学国家盐湖资源综合利用工程技术研究中心,上海200237

年份：2015

卷号：66

期号：10

起止页码：4007

中文期刊名：化工学报

外文期刊名：CIESC Journal

收录：CSTPCD;;EI(收录号：20154401454166);Scopus;北大核心:【北大核心2014】；CSCD:【CSCD2015_2016】；

基金：国家高技术研究发展计划项目(2011AA06A107)~~

语种：中文

中文关键词：废物处理;结晶;碳酸钙;晶型转变;溶剂萃取

外文关键词：waste treatment;crystallization;calcium carbonate;polymorph transformation;solvent extraction

摘要：氨碱法制碱过程中产生的大量蒸氨废液制约了纯碱工业的发展。本文对反应-萃取-结晶耦合工艺产物碳酸钙的晶型转变和结晶机理进行了研究。结果表明,在此耦合过程中,二氧化碳优先被有机相吸收,然后传递到水相进行反应,首先生成的是碳酸氢钙,之后迅速分解为无定形碳酸钙。温度对碳酸钙晶型影响显著,温度较高时,无定形碳酸钙优先转变为针状文石;温度较低时,无定形碳酸钙优先转变为球状球霰石。随后文石和球霰石均会通过溶解-重结晶作用逐渐转变为稳定的菱形方解石。常温下,反应过程中同时进行着新的球霰石的生成和球霰石转变为方解石两个过程,参与反应的二氧化碳浓度越高,晶体中球霰石的含量越高。
Distiller waste produced in ammonia-soda process restricts the development of soda industry. In this study, the polymorph transformation and crystallization mechanism of calcium carbonate in the reactive extraction-crystallization coupled process were investigated. The results show that carbon dioxide （CO2） is first absorbed by the organic phase and then transferred to the aqueous phase. Calcium bicarbonate is generated and then decomposed into amorphous calcium carbonate rapidly. Temperature has a significant effect on the polymorph of calcium carbonate. Needle-like aragonite forms preferentially at higher temperatures and spherical and flower-like vaterite forms preferentially at lower temperatures. Both of them will finally transform into rhombic calcite by dissolution and recrystallization. At 20℃, the formation of new vaterite and its transformation to calcite occur simultaneously in the coupled process. The content of vaterite in the particles increases with the increase of CO2 concentration.