| 摘要 |
FIELD: production of silicon dioxide. ^ SUBSTANCE: powder silicon dioxide contains admixtures lesser than 500 parts per billion and contains no carbon, preferably content of admixtures is lesser than 150 part per billion: Cu is lesser than 1 part per billion; Fe is lesser than 25 parts per billion; Ni is lesser than 2 parts per billion; Cr is lesser than 2 parts per billion; Ti is lesser than 3 parts per billion; Al is lesser than 31 parts per billion; Ca is lesser than 65 parts per billion; Mg is lesser than 12 parts per billion; Na is lesser than 12 parts per billion; K is lesser than 6 parts per billion and Li is lesser than 1 part per billion. Silicon dioxide is produced by hydrolysis of SiCl4 in flame of device where all contact surfaces do not contain metals. ^ EFFECT: enhanced efficiency of production of high-purity product. ^ 15 cl, 6 dwg, 1 tbl, 7 ex |
