Evaluation of the low temperature slurry catalyst, Copper Zinc oxide, in the conversion of Carbon monoxide using the water gas shift reactionfor hydrogen cleanup from biomass

Abstract

The Carbon monoxide (CO) present in synthesis gas (syngas) produced by the gasification of biomass is detrimental to the membranes used in Hydrogen (H2) purifiers as well as in proton exchange membranes (PEM) for fuel cells. Thus, CO must be completely removed or considerably reduced in the syngas. The main objective of this paper is to convert CO to Carbon dioxide (CO2) using the Water Gas Shift reaction (WGS) for the cleanup of H2 which is used in PEM fuel cells to produce combined heat and power. In this paper, the conversion performance of a commercially available Copper Zinc oxide (CuZnO) catalyst suspended in Ethylflo-164 oil was evaluated in the WGS reaction using a syngas simulation of 66% H2 and 34% CO. The temperature and steam to CO ratio inside the reactor were found to affect the catalytic activity of CuZnO; therefore, tests were conducted to achieve maximum CO conversion at175°C, 200°C, and 225°C. The best catalytic activity occurred at 225°C as the CO concentration in the output gas was reduced to 3.46%. An increase in the steam to CO ratio further reduced the CO concentration in the output gas at both 175°C and 200°C.The results of this research will eventually be compared to the performance of other catalysts in order to build the most efficient hydrogen synthesizing and purification biomass system at Farmingdale State College. The system will be composed of a gasifier, a WGS reactor, an H2 purification system, and a H2 storage system. The ultra-pure H2 achieved by the entire biomass system will be fed to Hydrogen Fuel Cell systems generating electrical power.