| 摘要 |
A method for the preparation of magnetic particulate matter coated with a protective layer of chromium(III) hydroxide, oxyhydroxide or oxide, optionally crosslinked with polyacrylic acid, which process comprises a first step of depositing a hydrogel of chromium(III) hydroxide onto magnetic material in a desired particulate form, a second step of heating to form chromium(III) hydroxide, oxyhydroxide or oxide, and a third optional step, which may precede or follow the said second step, of crosslinking with polyacrylic acid. The coated protected magnetic particles are useful for the preparation of composite magnetic polymeric particles for use in processes involving ion exchange, filtration and adsorption. |
