The bulk and internal gas-phase mixing characteristics of a new, smallest commercial Berty-type reactor (Autoclave Engineers), for use with gas-solid catalytic reactions, have been evaluated over a range of impeller speeds, pressures, flow rates, and catalyst particle sizes. Mixing in the bulk gas phase has been investigated using step change tracer experiments. These results show no measurable dead volume and good mixing for impeller speeds above 1000 rpm, at pressures above 100 psi and for all catalyst forms. The operating regime free from internal concentration gradients has been determined over pelleted, chunked, and powdered Ni/Al2O3 catalysts utilizing methanation of carbon monoxide as a probe reaction with a reactant flow rate of 8500 cm3(STP)/(g of catalyst.h). Performance in each case is summarized as a function of pressure, catalyst particle size, and impeller speed. The results show good internal mixing at or above a pressure of 80 psi and impeller speeds greater than or equal to 1000 rpm. Poor bulk and internal mixing occurs at atmospheric pressure.
