| abstract |
A process for the removal of fluoride from a spent chromium-based fluorination catalyst by contacting the catalyst with potassium hydroxide to produce a suspension of solid hydrated chromium oxide in aqeuous 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 (III) 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. |