| 摘要 |
PROBLEM TO BE SOLVED: To simply obtain high grade silicon in good productivity by hydrolyzing a pure tetraalkoxysilane having the contents of B, P and impurities controlled to specific values or less, respectively, and subsequently reducing the obtained highly pure silica. SOLUTION: This method for producing silicon for solar batteries comprises hydrolyzing a pure tetraalkoxysilane having a B content of <=0.1 ppm, a P content of <=0.1 ppm and a total metal impurity content of <=20 ppm preferably in the presence of a solvent (for example, methanol) and a catalyst (for example, carbonic acid) with water in an amount of 3-12 moles per mole of the tetraalkoxysilane, reducing the obtained highly pure silica preferably having a purity of >=99.99% preferably by an arc thermal reduction method and subsequently purifying the reduction product, for example, by a coagulation purification method. The pure tetraalkoxysilane is obtained, for example, by the superfractionation of a crude tetraalkoxysilane obtained from powdery metal silicon and methanol as raw materials in the presence of sodium methylate catalyst. |
