A COST-EFFECTIVE CATALYST FOR GASIFICATION OF POWDER RIVER BASIN COAL

摘要

The present invention generally relates to a catalytic gasification of coal. Catalytic gasification of a Wyodak low-sulfur sub-bituminous coal from the Powder River Basin of Wyoming was investigated using an inexpensive sodium carbonate catalyst applied via incipient wetness impregnation. Experiments in an atmospheric pressure fixed-bed laboratory gasifier were performed to evaluate the effects of reaction temperature, feed gas steam content, and Na₂CO₃ loading on the catalytic gasification of the Wyodak coal. The temperature range investigated (700-900°C) was selected with consideration of the Na₂CO₃ melting point (850°C) to reduce the loss by volatilization of sodium. Sodium was found to be active during both pyrolysis and gasification steps. The catalyst was most cost-effective at addition levels of approximately 3 wt%. The random pore model provided a good fit to the conversion versus time data collected under both the catalytic and the uncatalytic conditions.