Products analysis of Shendong long-flame coal hydropyrolysis with iron-based catalysts

Abstract

This paper focuses on the effect of Fe2O3, Fe2S3, Fe2O3-oleic acid, FeS, and FeSO4 on hydropyrolysis of Shendong long-flame coal. The experiments were conducted at 650°C and 0.1MPa in a novel lab-scale-fixed-bed reactor. For non-catalytic hydropyrolysis process, the char, tar and gas yields were 73.5wt.%, 7.9wt.%, and 12.1wt.%, respectively. In terms of catalytic hydropyrolysis, the highest conversion of coal and tar yields (8.4wt.%) was observed when Fe2O3-oleic acid was used. The strong decomposition capability of the iron-based catalysts had negative effects on the tar yield, but favored the formation of the n-hexane soluble compounds. Particularly with Fe2S3 as a catalyst, the tar yield decreased from 7.9wt.% to 7.0wt.%, while the n-hexane soluble contents of the tar increased from 70.6wt.% to 81.0wt.%. The yield of lightweight components increased about 0.1wt.%. A molecular weight reduction in the tar and the heavy compounds, which confirmed the ability of iron-based catalysts to make the heavy oil be light. The characteristic temperatures of char gasification with CO2 had little change.