The loading methods of hydrogenated metal include impregnation, co-sedimentation (beating) and mixed kneading.
Impregnation method is to match hydrogenated metal into a certain concentration of solution, the carrier is added to the solution, the general impregnation solution is twice the weight of the carrier, impregnation at a certain temperature for a certain time, separation of impregnation solution, drying, roasting.
The co-sedimentation method is to co-sink the aqueous solution of hydrogenated metal salt with the carrier of aluminum silicate, then washing, shaping, drying, calcination.
The beating method is to add the hydrogenated metal salt solution to the aluminum silicate slurry. Then washing, molding, drying, roasting.
Mixed kneading method is to knead the fine powder of acid carrier together with metal oxide or metal salt, and add adhesive, kneading, extrusion molding, drying, roasting.
Different catalyst preparation methods have their own advantages and disadvantages. The metal load of co-sedimentation (beating) method is not limited, and the dispersion is good, but the metal loss is large, the impurity removal is difficult, the mechanical strength fluctuates greatly. The mixed kneading method has the advantages of simple operation, low technical requirements, unrestricted metal load, good mechanical strength and high yield, but its activity is generally lower than that of impregnation method.The catalyst prepared by impregnation method has good hydrogenation activity, high mechanical strength and excellent catalytic performance, but the metal loading capacity is limited, the preparation technology and process are more complicated than that by mixed kneading method, the problems of recycling and storage of impregnation solution exist.