A parametric investigation of impregnation and drying of supported catalysts

Supported metal catalysts are used in many industrial processes. The performance of a catalytic process is intimately related to the metal profile in the support, which is determined by the conditions that are applied during impregnation and drying. In this work, theoretical models are established to predict impregnation and drying during preparation of supported catalysts. The sensitivity of the metal distribution during impregnation and drying with respect to the physical and processing parameters are examined. The connection between impregnation and drying is also taken into account. Regime maps are computed to investigate the variation of the final metal profiles as a function of the parameters, and it is found that uniform profiles can be obtained by increasing the impregnation time and the metal diffusion while egg-shell profiles can be obtained by increasing the drying temperature or decreasing the humidity of the drying air. For high-metal-concentration systems, metal crystallization has a significant effect on the generation of egg-shell profiles during drying.