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.

主权项

1. A coal gasification method, comprising:
forming a reaction mixture comprising a coal derived solid and a single catalyst consisting of aqueous sodium carbonate by mixing the coal derived solid and the single catalyst, wherein the single catalyst is present in the reaction mixture at a concentration no higher than about 5 wt %; heating the reaction mixture to a target temperature between about 700° C. and about 900° C.; maintaining the reaction mixture at a pressure below 1 atm.; contacting the reaction mixture with water vapor; and forming carbon monoxide from the reaction mixture.