摘要
电石渣是聚氯乙烯(PVC)生产过程中产生的一种高钙固体废弃物,是一种优良的二次钙资源,采用碳化法合成高附加值碳酸钙,既能实现电石渣资源化利用,又能减少CO_(2)排放。本文提出了一种以电石渣为原料矿化CO_(2)联产碳酸钙晶须的技术,考察了CO_(2)流速、反应温度、反应时间对碳酸化产物晶型与形貌的影响,结果表明:浸出液矿化CO_(2)的优化工艺条件为CO_(2)流速100 mL/min、反应温度80℃、反应时间90 min;通过调节工艺条件实现了对碳酸化产物晶型与形貌的调控,在优化条件下所获产物晶型为单一纤维状文石;碳化反应中CO_(2)流速、反应温度和反应时间的增加均有利于碳酸化产物向热力学性质更稳定的晶型转变;此外,碳酸化反应滤液可循环用于Ca(OH)2的浸出。
Carbide slag is a kind of solid waste with high calcium content produced in the production process of polyvinyl chloride(PVC).It is an excellent secondary calcium resource.The synthesis of high value-added calcium carbonate by carbonization method can not only realize the resource utilization of carbide slag,but also reduce the emission of CO_(2).This paper proposes a technology to mineralize CO_(2)and produce calcium carbonate whiskers with carbide slag as raw material.The effects of CO_(2)flow rate,reaction temperature and reaction time on the crystal form and morphology of carbonation products were investigated.The results show that the optimized process conditions for mineralizing CO_(2)in leachate were CO_(2)flow rate of 100 mL/min,reaction temperature of 80℃,and reaction time of 90 min;By adjusting the process conditions,the crystal form and morphology of the carbonated product are controlled.The crystal form of the product obtained under the optimized conditions is a single fibrous aragonite;The increase of CO_(2)flow rate,reaction temperature,and reaction time in carbonation reaction is beneficial for the transformation of carbonation products into more thermodynamically stable crystal forms;In addition,the filtrate from the carbonation reaction can be recycled for the leaching of Ca(OH)2.
作者
姚金
丁文金
陈秋菊
YAO Jin;DING Wenjin;CHEN Qiuju(Key Laboratory of Ministry of Education for Solid Waste Treatment and Resource Recycle,Southwest University of Science and technology,Mianyang Sichuan 621010,China;Sichuan Engineering Lab of Non-metallic Mineral Powder Modification and High-value Utilization,Mianyang Sichuan 621010,China)
出处
《化工矿物与加工》
2025年第2期9-16,共8页
Industrial Minerals & Processing
基金
四川省自然科学基金面上项目(2023NSFSC0348)
四川省科技创新创业苗子工程重点项目(2023JDRC0070)。
关键词
电石渣
碳酸钙晶须
CO_(2)矿化
碳酸化
滤液
文石
晶型
carbide slag
calcium carbonate whisker
CO_(2)mineralization
carbonation
filtrate
aragonite
crystal form
