Electrical conductivity and viscosity of cryolite electrolytes for solar grade silicon(Si-SoG) electrowinning  

太阳能级硅电沉积用冰晶石熔盐的电导率和黏度(英文)

作　　者：Michal KORENKO Zuzana VASKOV Frantiek IMKO Michal IMURDA Marta AMBROV 石忠宁[3] 

机构地区：[1]Institute of Inorganic Chemistry, Slovak Academy of Sciences,Dúbravská cesta 9,SK–84536 Bratislava, Slovakia [2]Institute of Inorganic Chemistry, Technology and Materials, Slovak University of Technology,Radlinskeho 9,SK–81237, Bratislava, Slovakia [3]东北大学材料与冶金学院

出　　处：《Transactions of Nonferrous Metals Society of China》2014年第12期3944-3948,共5页中国有色金属学报（英文版）

基　　金：supported by the Science and Technology Assistance Agency (APVV-0460-10 and SK-CN-0029-12);Slovak Grant Agency (VEGA 2/0116/14 and VEGA 2/0095/12);the National Natural Science Foundation of China (51322406);the Program for New Century Excellent Talents (NCET-13-0107);Ministry of Education of China

摘　　要：Electrical conductivity of molten binary and ternary mixtures based on the system NaF-AlF3-SiO2 was investigated by means of a tube–cell （made of pyrolytic boron nitride） with stationary electrodes. Viscosity of the binary system Na3AlF6-SiO2 was measured by computerized torsion pendulum method. It was found that conductivity and viscosity varied linearly with temperature in all investigated mixtures. Obtained content dependence of electrical conductivity （isotherms） was divided into two parts. First, one represented the content region up to 10%（mole fraction） of SiO2;second, the region was with a higher content of SiO2 （from 10%up to 40%）. While the conductivity considerably decreased with content of SiO2 in the second part; it surprisingly rose in the low content range. A small addition of SiO2 to the molten cryolite （up to 10%） could slightly increase viscosity, but had no influence on the slope of this dependence since it is responsible for a glassy-networks formation in the melt. Further addition of SiO2 to the molten cryolite had a huge effect on the viscosity.以热解碳化硼管作电导池,用固定电导池常数法研究由Na F-Al F3-Si O2构成的二元系和三元系熔盐的电导率;用扭摆法测定Na3Al F6-Si O2二元系的黏度。研究发现,所研究熔盐体系的电导率和黏度均与温度呈直线关系。Na3Al F6-Si O2二元系的电导率与Si O2含量关系曲线可分为0-10%和10%-40%（摩尔分数）两段,当SiO 2含量超过10%之后,电导率随着Si O2含量的增加而快速下降,而当Si O2含量小于10%时,电导率随着Si O2含量的增加而缓慢增加。在Si O2含量大于10%的冰晶石熔盐中添加少量的SiO 2,熔盐的黏度增加,但增加的趋势基本相同,这与熔盐中形成玻璃网状结构的离子团有关。当在冰晶石熔盐中继续增大Si O2含量到50%时,黏度发生急剧变化。

关 键 词：electrical conductivity VISCOSITY solar grade silicon molten salts molten cryolite-silica melts 

分 类 号：TQ127.2[化学工程—无机化工] TM914.4[电气工程—电力电子与电力传动]