The Kinetics of the Reduction of Lead Monoxide by Hydrogen
RV Culver, IG Matthew and ECR Spooner
Australian Journal of Chemistry
15(1) 40 - 55
Published: 1962
Abstract
The rate of reduction of fused lead monoxide particles in a differential reactor with H2-N2 and H2-H2O mixtures has been measured by absorbing the H2O of reaction or chemically analysing the product, Pb-PbO. After falling from a high initial value, the reduction rate remains virtually constant until 40-50% of the PbO has been reduced, and then slowly declines. The rate of reduction is independent of the gas flow rate from 5-151. S.T.P./min and not markedly influenced by variations in particle size from -36+52 to -7+10 mesh B.S.S. With H2-N2 mixtures the rate of reduction of PbO at 575 and 675 °C is proportional to pH2, and with H2-H2O mixtures at 575 °C it is proportional to pH2/(1+0.5pH2O), where pH2, and pH2O are the partial pressures of H2 and H2O, respectively. The activation energy for reduction with H2-N2 and H2-H2O mixtures over the temperature range 475-775 °C is 39 kcal/g-mole. Chemisorption of H2 on the PbO appears the most likely rate controlling step at the Pb-PbO interface. Rates of reduction over the steady rate period, k0, are correlated by the expression k0=f(R)[pH2/(1+0 5 pH2O)] exp(-39 000/RT), where f(R) is a parameter related to particle shape and size.https://doi.org/10.1071/CH9620040
© CSIRO 1962