| 摘要 |
PURPOSE:To reactivate a catalyst and to extend the life thereof by adding a phosphorus-containing substance to a used catalyst and replenishing an eluted phosphoric acid component. CONSTITUTION:A phosphorus-containing substance such as phosphoric acid or phosphoric ester is dissolved or suspended in a solvent such as water, methyl alcohol or ethyl alcohol and a catalyst lowered in its function during use and containing phosphoric acid or a condensate thereof is immersed in the resulting solution or suspension and drained to be dried. This reactivation can be carried out without taking out the catalyst from a reactor in a case using a fixed bed system. In the case of a batchwise system, the phosphorus-containing substance is also added other than the catalyst in reacting ammonia or ethylenediamine with monoethanolamine to reactivate the catalyst. |
