| 摘要 |
PROBLEM TO BE SOLVED: To provide a heavy metal-containing liquid waste treatment process for fixing heavy metal in a solution or fluid dispersion containing heavy metal to a solid material stably for a long period.SOLUTION: The heavy metal-containing liquid waste treatment process is provided that comprises: forming a sol by adding to solution or fluid dispersion containing heavy metals silica powders having particle size below 100 μm in an amount such that the content of silica in the sol is between 10 wt.% and 90 wt.%, under the condition that the pH of the sol is not higher than 4; adding to the sol at least one alkoxysilane in such an amount to obtain a silica/ alkoxysilane molar ratio higher than 6; raising the pH of the sol to a value above 4, thus forming hydrogel; drying the hydrogel, thus obtaining a dried gel; and sintering the dried gel, thus obtaining a vitreous silica product.SELECTED DRAWING: None |
