| abstract |
1. A PROCESS OF PREPARING A CATALYST OR CATALYST SUPPORT WHICH COMPRISES MIXING PREFORMED ALUMINA PARTICLES WITH SILICA SOL IN AN AMOUNT SUFFICUENT TO FOEM A SURFACE COATING OF SIO2 ON SAID ALUMINA WHICH COATING AFTER DRYING AND CALCINING CONSTITUTES LESS THAN 2.5% SIO2, BASED ON THE WEIGHT OF A12O3 BUT IS SUFFICIENT TO ENHANCE THE HYDROTREATING ACTIVITY OF SAID CATALYST, AND CONTACTING SAID ALUMINA PARTICLES BEFORE, DURING OR AFTER SAID MIXING WITH AN ACTIVATING AGENT IN THE FORM OF A COMPOUND EFFECTIVE TO MAKE THE ALUMINA MORE REACTIVE WITH THE SILICA OF SAID SILICA SOL EITHER BY CONVERTING A PORTION OF THE ALUMINA TO A WATER SOLUBLE STATE OR BY COATING THE ALUMINA WITH A WATER SOLUBLE ALUMINUM COMPOUND, SAID ACTIVATING AGENT BEING SELECTED FROM THE GROUP CONSISTING OF ACETIC ACID, FORMIC ACID, ALUMINIUM ISOPROPOXIDE, CHLOROHYDROL AND TETRAMETHYLAMMONIUM HYDROXIDE. |