含钙镁渣液离子膜碳化电解制备CaCO_(3)  

Preparation of calcium carbonate by ion-exchange membrane carbonization electrolysis of calcium-containing magnesium slag solution

作　　者：李广涛 刘燕 张廷安 林胜男 LI Guangtao;LIU Yan;ZHANG Tingan;LIN Shengnan(School of Metallurgy,Northeastern University,Shenyang 110000,China;Chinalco Southeast Materials Institute(Fujian)Technology Co.,Ltd.,Fuzhou 350015,China)

机构地区：[1]东北大学冶金学院,沈阳110000 [2]中铝东南材料院(福建)科技有限公司,福州350015

出　　处：《有色金属科学与工程》2025年第1期25-34,共10页Nonferrous Metals Science and Engineering

基　　金：中国博士后科学基金第16批特别资助(站中)项目(2023T160088);国家自然科学基金青年基金资助项目(52304324)。

摘　　要：镁渣是皮江法炼镁产生的固体废弃物,检测发现镁渣中存在大量CaO和Ca_(2)SiO_(4)物相,是良好的钙源。加入盐酸浸出镁渣得到的净化液为比较纯净的CaCl_(2)溶液,CaCl_(2)含量约为250 g/L,再经过电解转化为Ca(OH)_(2)溶液,在电解槽阴极通入CO_(2)可以制备出轻质CaCO_(3)产品。因此,本文以配置CaCl_(2)浓度为250 g/L的溶液为阳极液,通过阳离子交换膜电解技术并在阴极通入CO_(2),得到CaCO_(3)产物。通过改变阴极NaCl浓度、CO_(2)流量、电流密度和电解时间,考查各因素对电解过程的影响。结果表明:当实验条件为阴极NaCl浓度为50 g/L、CO_(2)流量为50 mL/min、电流密度为0.05 A/cm^(2)和电解时间2 h时,电解效果最好。此时得到CaCO_(3)产物质量为4.41 g,电解过程能耗为2.79 kW·h/kg。对比直接电解得到的Ca(OH)2,发现直接电解有明显质量损失,且能耗增大,所以电解过程中在阴极通入CO_(2)是很有必要的。Magnesium slag is a solid waste produced by Pidgeon process.It is found that there are a large number of CaO and Ca_(2)SiO_(4)phases in magnesium slag,which is a good calcium source.The concentration of CaCl_(2)solution obtained by adding hydrochloric acid to leach magnesium slag is about 250 g/L,and then converted into Ca(OH)_(2) solution by electrolysis.Light CaCO_(3)products can be prepared by introducing CO_(2)into the cathode of the electrolytic cell.Therefore,in this paper,using 250 g/L CaCl_(2)solution as the anode liquid,CaCO_(3)product was obtained by cation exchange membrane electrolysis technology and CO_(2)was introduced at the cathode.The effects of various factors on the electrolysis process were investigated by changing the cathode NaCl concentration,CO_(2)flow rate,current density and electrolysis time.The results show that the electrolysis effect is the best when the experimental conditions are cathode NaCl concentration of 50 g/L,CO_(2)flow rate of 50 mL/min,current density of 0.05 A/cm^(2)and electrolysis time of 2 h.At this time,the mass of CaCO_(3)product was 4.41 g,and the energy consumption per unit mass of electrolysis process was 2.79 kW·h/kg.Compared with direct electrolysis to obtain Ca(OH)_(2),it was found that direct electrolysis had obvious mass loss and increased energy consumption,so it was necessary to introduce CO_(2)into the cathode during the electrolysis process.

关 键 词：镁渣 阳离子交换膜 电解 Ca(OH)_(2) CaCO_(3) 

分 类 号：TF111.52[冶金工程—冶金物理化学] TQ151.8[化学工程—电化学工业]