Metal Sulfide Assisted Coal Catalytic Hydrogenated Microwave Pyrolysis

Abstract

The efficient cleaning conversion of coal is more and more attracted due to resource exhaustion and environmental pollution. To improve the yield and quality of products of coal pyrolysis, the catalytic hydrogenated microwave pyrolysis was introduced, and the effects of metal sulfide on hydrogenated microwave pyrolysis were focused on discuss via the detection methods of proximate and ultimate analyses, SEM-EDS, FT-IR and GC-MS in this work. The results shown that because of the “hot-spot” effect and the characteristics of electromagnetic loss of metal sulfide, the temperature-rising rates with catalysts were obviously higher, but the final pyrolysis temperatures with or without catalyst were almost close. Higher temperature-rising rate with catalysts made the yield of liquid product more, which the yields of liquid product with MoS2 and FeS2 catalyst were 28.4 wt.% and 27.1 wt.%. The carbon distributions indicated that carbon in solid and gaseous products transferred into liquid product, when the catalysts added into pyrolysis reactions. The quality of tar with catalyst was improved, and the component content of light oil, intermedium oil and heavy oil were 67.55 wt.%, 27.98 wt.% and 4.47 wt.% for MoS2 catalyst, in which the content of light oil increased by 10.30 times than that without catalyst. The thermal effect and catalysis of metal metal sulfide made complex aromatic compounds more thorough cracking, improved the amount and active of free hydrogen. Actived free hydrogen further enhanced cracking of heavy oil, resulting in the content of hydrogen in gaseous with catalysts decrease, and the content of light oil increased.