Catalytic Gasification Activity of Na2CO3 and Comparison with K2CO3 for a High-Aluminum Coal Char

The catalytic performance of Na 2 CO 3 for high-aluminum coal gasification was specially investigated, and the effect of the ash constituents in Sunjiahao (SJH) high-aluminum coal char on the catalytic activity of Na 2 CO 3 and a comparison with that of K 2 CO 3 were also studied through steam gasification experiments of SJH char catalyzed by Na 2 CO 3 or K 2 CO 3 carried out using a thermogravimetric analyzer and a fixed-bed reactor at 800 °C, respectively. The results indicate that the steam gasification rates of SJH char and acid-treated SJH char catalyzed by Na 2 CO 3 are higher than those by K 2 CO 3 with equal masses of catalyst. Na 2 CO 3 can be used as the catalyst for high-aluminum coal gasification at 800 °C. The effect of the ash components on the catalytic activity of Na 2 CO 3 is larger than that of K 2 CO 3 in the catalytic steam gasification of SJH high-aluminum coal char at 800 °C. The X-ray diffraction (XRD) patterns of the steam gasification ashes of SJH char impregnated with Na 2 CO 3 or K 2 CO 3 reveal that the main composition is aluminosilicate, which is proved to have no catalytic activity. For catalytic steam gasification of acid-treated SJH char, the catalytic action of Na 2 CO 3 is better because of the superior mobility and poor volatility of Na 2 CO 3 .