Partial Purification of Metallurgical Silicon by Acid Extraction
Partial Purification of Metallurgical Silicon by Acid Extraction
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DOI：
10.1149/1.2119730
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发表时间：
1983-02
影响因子：
3.9
通讯作者：
T. Chu;S. Chu
中科院分区：
文献类型：
--
作者：
T. Chu;S. Chu
冶金级硅可以通过酸提取技术纯化，因为在制造过程中熔体凝固期间杂质在晶界处偏析。本文详细研究了用王水、盐酸和等体积的硫酸-硝酸混合液进行酸浸法部分提纯粉末冶金硅的方法。王水是最有效的，并在大气压下的金属杂质的去除程度已被确定为一个函数的持续时间的蒸馏。虽然可以去除80%以上的金属杂质，但杂质的溶解是一个缓慢的过程。通过在高温和压力下在封闭系统中进行王水提取，溶解速率可以增加许多倍。
Metallurgical grade silicon may be purified by the acid extraction technique because of the segregation of impurities at grain boundaries during the solidification of the melt in the manufacturing process. The partial purification of pulverized metallurgical silicon by refluxing with acids has been investigated in detail using aqua regia, hydrochloric acid, and an equivolume mixture of sulfuric acid and nitric acid. Aqua regia is most effective, and the extent of removal of metallic impurities under atmospheric pressure has been determined as a function of the duration of refluxing. Although more than 80% of metallic impurities can be removed, the dissolution of impurities is a slow process. The rate of dissolution may be increased many folds by carrying out the aqua regia extraction in a closed system at high temperatures under pressure.