Impregnation process for preparing a catalyst precursor and the catalyst

摘要

A process for preparing a catalyst precursor is disclosed, which comprises subjecting, in an initial treatment stage, a slurry of a catalyst support, an active catalyst component precursor, and water, to treatment at elevated temperature of from 60 to 95°C and at sub-atmospheric pressure, to impregnate the support with the precursor and to dry the impregnated support partially. The initial treatment stage does not continue beyond a point where the impregnated carrier has a loss on ignition (LOI) which is less than 1.2 times its loss on ignition at incipient wetness LOIiw. In a subsequent treatment stage, the partially dried impregnated support is subjected to more vigorous drying at elevated temperature of from 60 to 95°C and at sub-atmospheric pressure such that the temperature in the subsequent treatment stage exceeds that in the initial treatment stage and/or the sub-atmospheric pressure in the subsequent treatment stage is lower than in the initial stage, thereby to obtain a vigorous drying of the impregnated carrier in the subsequent treatment stage than in the initial treatment stage, with a dried impregnated carrier or support thereby being produced, and which is calcined to obtain the catalyst precursor. The catalyst precursor is reduced, to obtain a catalyst.