Purification of metallurgical grade silicon by electrorefining in molten salts  

熔盐电解精炼提纯金属硅(英文)

作　　者：蔡靖[1] 罗学涛[1] 卢成浩[1] Geir Martin HAARBERG Annabelle LAURENT Ole Edvard KONGSTEIN 王淑兰[4] 

机构地区：[1]厦门大学材料科学与工程系,厦门361005 [2]Department of Materials Technology, Norwegian University of Science and Technology [3]SINTEF, Trondheim NO-7465, Norway [4]东北大学化学系,沈阳110004

出　　处：《Transactions of Nonferrous Metals Society of China》2012年第12期3103-3107,共5页中国有色金属学报（英文版）

基　　金：Project (2007J0012) supported by the Natural Science Foundation of Fujian Province, China;Project (019811) supported by Foxy in the 6th Framework Program, European Commission

摘　　要：Electrochemical studies on silicon deposition were performed in molten salt electrolytes. Purification of metallurgical grade silicon by electrorefining was carried out in molten Si-chloride salts at temperatures from 973 K to 1223 K. It was found that the use of a liquid alloy anode of silicon and copper was beneficial in molten CaCl2 with NaCl, CaO and dissolved Si. ICP-AES analysis results showed efficient removal of metal impurities, such as titanium, aluminum and iron, which are present in significant quantities in the feedstock. The contents of boron and phosphorus in the silicon after electrorefining were reduced from 36×10-6 and 25×10-6 to 4.6×10-6 and 2.8 ×10-6, respectively. The energy consumption of electrorefining was estimated to be about 9.3 kW?h/kg.对熔盐电解质中硅的沉积过程进行电化学研究。在 973~223K,在硅氯化物熔盐中采用电解精炼提纯金属硅。结果表明,液态硅铜合金阳极有利于 CaCl2-NaCl-CaO-Si 熔盐体系的电解精炼。ICP-AES 分析结果显示,通过电解精炼可有效去除原料中大量的钛、铝、铁等金属杂质,硅中的硼和磷含量分别由 36×106和 25×106降低至 4.6×10 6和 2.8×10 6,电解能耗约为 9.3 kW·h/kg。

关 键 词：ELECTROREFINING molten salt Si-Cu alloy SILICON PURIFICATION energy consumption 

分 类 号：TQ127.2[化学工程—无机化工]