Dilute solutions (132 ppm) of formic acid in water were oxidized with air in a trickle-bed reactor at 212° to 240°C and 40 atm. Particles 0.291 and 0.0541 cm in diameter, prepared from a commercial CuO · ZnO catalyst, were used to provide a model system for studying water purification by catalytic oxidation.

Differential reactor runs were made to measure the global rate of reaction. These data were compared with predicted rates from the known intrinsic kinetics and intraparticle diffusivities, and the mass transfer coefficients measured in Part I.

High conversion (of formic acid) data were also obtained in order to test models for trickle-bed reactors. Experimental conversions agreed reasonably well (within 10%) with predicted values based upon intrinsic kinetics and the several transport rates. Axial dispersion was found to be less important than gas-to-liquid mass transfer and intraparticle diffusion. In our laboratory studies (reactor I.D. = 1 in.) careful arrangements were made to obtain nearly uniform distribution of liquid over the reactor cross section. Hence effects of maldistribution, which may be important in large-scale reactors, were minimized.