Study On Catalytic Graphitization Of Shenfu Coal And Macerals

Graphite materials are widely used in the fields of aviation, aerospace, nuclear, militaryindustrials, and many civilian industrials, owing to their super performances such as hightemperature resistance, corrosion resistance, self-lubricating, heat shock resistance, highthermal conductivity and electrical conductivity, etc, compared to other materials. Anthraciteis one of the carbonaceous materials for preparing graphite materials. Because anthracite is akind of scare resource, we aim to explore the graphitization of bituminous coal in this paper.This study highlighted the catalytic graphitization process of Shenfu coals and itsmacerals, and investigated the effects of catalyst type and amount, pulverized coal particlesize and heat treatment temperature on the catalytic graphitization process of Shenfu coals andmacerals. The structures of graphitization products were characterized using XRD, Raman,and the micro morphology, structure and elementary composition of Shenfu coal before andafter graphitization process by means of SEM, EDS, furthermore, the mechanism of catalyticgraphitization was examined. The main research contents and obtained results are presentedas follows:(1) The influences of particle size and temperature of graphitization process of Shenfucoal were studied. The micro morphology, structure and elements of graphitization productsamples were characterized by SEM, EDS, Raman, XRD, etc. The results show that thedecrease of particle size of Shenfu coal facilitates the graphitization process, the smaller theparticle size, the structure of the microcrystal is more regularity. When the particle size (D90)of Shenfu coal is below20μm, the degree of graphitization of samples is65.93%after hightemperature graphitization treatment at2500oC.(2) The structure difference of vitrinite and fusinite of Shenfu coal after high temperaturegraphitization treatment was investigated. The results demonstrate that when the particle size(D90) of vitrinite and fusinite of Shenfu coal is no less than75μm, after thermal treatment ofhigh temperature2500oC, the degrees of graphitization of samples are54.19%and65.93%, respectively; the fusinite is easier to be graphitized as compared to the vitrinite.(3) The influence of ferric chloride on the graphitization of Shenfu coal was explored.When the particle size (D90) of Shenfu coal is below20μm, after thermal treatment of hightemperature2500oC, the samples exhibit a77.56%degree of graphitization and0.3373nm oflayer spacing using iron chloride as a catalyst and keeping the ratio of pulverized coal toboron element at5/1.(4) The effect of boric acid on the graphitization of Shenfu coal was studied. When theparticle size (D90) of Shenfu coal is below20μm, after thermal treatment of high temperature2500oC the samples exhibit a80.35%degree of graphitization and0.3371nm of layer spacingusing boric acid as a catalyst and keeping the ratio of pulverized coal to boron element at5/1.(5)The degree of graphitization can be improved by thermal treatment on Shenfu coalusing boric acid as a catalyst and keeping the ratio of pulverized coal to boron element at5/1under1500oC, then aromatic structure layer of organic basic unit in coal is enhanced.