高温煤焦油中的固体颗粒对其临氢热反应生焦的影响

摘要

以一种高温煤焦油为原料,添加不同含量的固体颗粒在高压釜中进行临氢热反应,提取反应后的焦炭.通过XRD,XPS,FT-IR,UV-VIS,SEM等手段对固体颗粒和焦炭进行表征分析,考察了固体颗粒对其临氢热反应生焦的影响.结果表明,添加适量的固体颗粒后,高温煤焦油临氢热反应后的沥青质含量相对较高,生成的次生甲苯不溶物显著降低.固体颗粒的表层含有约为7％的极性含氧基团和1.4％的硫、氮极性基团,对沥青质具有较强的吸附能力.煤焦油中的沥青质在被固体颗粒吸附后,在反应体系中呈现出高分散状态,不容易聚集缩合生焦,生成的悬浮焦的颗粒粒径也相对较小,主要以高分散状态存在于反应体系中,在高压釜底部的沉积焦较少.%A kind of high temperature coal tar was selected as an experimental raw material.The thermal reaction at hydrogen atmosphere was carried out under the different contents of solid particles in an autoclave reactor.Then the coke was separated from reaction product.The solid particles and the coke were characterized and analyzed by X-ray diffraction,X-ray photoelectron spectroscopy,FT-IR,UV-VIS and scanning electron microscope.Results showed that a higher quantity of asphaltenes was obtained after a thermal reaction with an appropriate amount of solid particles,while the amount of secondary toluene-insoluble decreased significantly.The surface matter of the solid particles was mainly organic compounds,containing about 7％ polar oxygen groups and 1.4％ polar sulfur and nitrogen groups.Due to the strong adsorption ability of solid particles to the asphaltenes,the asphaltenes in the coal tar exhibited a high dispersibility and was uneasy to be condensed to coke.Besides,the particle size of suspended coke was relatively small,existing in the reaction system in a high dispersion,with comparatively little depositional coke at the bottom of autoclave.