Kinetics of low‐temperature catalytic combustion of ethylene at wet conditions for postharvest storage applications

The study addresses the reduction of ethylene levels in postharvest storage applications using a selected Pd‐Zn‐Sn/TiO2 catalyst (US Patent 11065579) capable of reacting trace concentrations of ethylene at temperatures as low as 278 K and relative humidity as high as 90%. The rate law is derived from data collected using a constant volume batch reactor, and a model for a storage room with an associated isothermal packed bed reactor is developed. The amount of catalyst required to maintain an ethylene concentration of 0.1 ppmv in a room containing 20 tons of fruit having an ethylene metabolism of 0.1 μl/kg h was calculated as a function of air temperature and water content. While the catalyst can continuously remove ethylene from saturated, refrigerated air, the amount of catalyst required can be reduced significantly by incorporating conventional air conditioning solutions upstream of the catalyst bed. Such combined systems and their functions are discussed.