在加压固定床反应器中研究了碱金属K对褐煤加氢气化的催化作用,考察了温度、压力和催化剂添加量对褐煤加氢气化反应性能的影响。结果表明,碱金属K对褐煤加氢气化具有良好的催化效果,气化反应的碳转化率约为95%,产品气中甲烷的质量分数可达89%;升高温度、提高压力和增加催化剂添加量均能明显提高气化反应性能,催化剂的饱和添加量约为15%。利用扫描电子显微镜(SEM)和气体吸附/脱附分析,对不同催化剂添加量煤样的表面形态和孔结构进行分析,发现比表面积和孔容积随K添加量的增加先减少后增大。
Effect of alkali metal K on the hydrogasification of lignite was studied in a pressurized fixed-bed reactor,and the effects of temperature,pressure and catalyst loading on the reactivity of hydrogasification of lignite coal were examined.The experimental results show that the alkali metal K has a superior catalysis on the hydrogasification of lignite,and the carbon conversion of hydrogasification and the methane content in gaseous products can be up to 95% and 89%,respectively.The gasification reactivity can be enhanced obviously by increasing temperature,pressure and catalyst loading,and the catalyst loading saturation level is about 15%.The surface morphology and pore structure of coal samples with different catalyst loadings have been analyzed using scanning electron microscope(SEM) and gas adsorption/desorption analysis,which indicates that the specific surface areas and total pore volume decrease initially,and then increase with the increasing of catalyst loading.