Catalytic Decomposition of Hydrogen Peroxide by Manganese-Alumina

摘要

Kinetic and deactivation studies conducted in a tubular flow reactor for the decomposition of hydrogen peroxide over manganese dioxide supported on alumina are reported. Catalytic decomposition of hydrogen peroxide is applicable to many areas of food processing involving sterilization of food products. Of special interest, is the potential use of stable inorganic catalysts in conjunction with immobilized catalase in the economical conversion of hydrogen peroxide into water and oxygen. In such an operation the inorganic catalyst could be used at the top of a tubular flow reactor in the presence of high peroxide levels of an incoming food product stream; the highly active immobilized catalase then could be used as the bottom portion of the catalyst bed in the same reactor to remove all traces of hydrogen peroxide leaving the inorganic catalyst bed. Experimental methods for these studies are described. Results indicate that manganese-alumina is a satisfactory catalyst for hydrogen peroxide decomposition either alone or with immobilized catalase. Kinetics of the system appear to be first order over the range of variables studied, but corrections for the rate constants are required due to particle size of feed buffer ions. Ions such as citrate and phosphate severely inhibit catalytic activity.