| 摘要 |
<p>PCT No. PCT/GB93/01889 Sec. 371 Date Mar. 17, 1995 Sec. 102(e) Date Mar. 17, 1995 PCT Filed Sep. 7, 1993 PCT Pub. No. WO94/06558 PCT Pub. Date Mar. 31, 1994A process for the removal of fluoride from a spent chromium-based fluroination catalyst by contacting the catalyst with potassium hydroxide to produce a suspension of solid hydrated chromium oxide in aqueous potassium fluoride. The solid hydrated chromium oxide may be separated from the solution, washed with water and/or aqueous acid, and contacted with nitric acid to produce a chromium (HI) nitrate solution from which a chromium-based catalyst may be prepared by precipitation of hydrated chromium oxide therefrom with aqueous alkali, and washing, drying and calcining the hydrated chromium oxide.</p> |
