氯化锌浮沉上浮煤的热解特性

Pyrolysis Characteristics of Flotation Cleaned Coal Getting from ZnCl_2 Float-and-sink Method

利用氯化锌溶液对陕西原煤进行浮沉,并对上浮煤热解特性进行考察,结果表明:氯化锌溶液密度越低,浮沉得到的上浮煤热解焦油收率越高,在密度为1.3g/cm^3时,焦油收率最大,为15.07%.利用傅立叶红外光谱(FTIR)对样品结构的分析表明,浮沉得到的上浮煤中Si—O—Si基团相对含量降低,酚和醚类的C—O键相对含量显著增加.上浮煤中脂肪烃结构富集,且脂肪烃侧链的长度和侧链化程度增加,但浮沉对芳环缩聚度没有影响.热解过程中,浮沉不改变各类化学键的初始反应活化能,但脂肪烃的富集使热解反应中易断键类物质的含量增加,因而热解过程总失重量增加,焦油收率增大.

The demineralized coal was prepared by float-and-sink method used ZnCl2 solution,the pyrolysis characteristics of coal were investigated.The results show that the lower density of the ZnCl2 solution is,the higher tar yield of flotation coal pyrolysis is obtained,and the biggest tar yield is 15.07%when the density is 1.30 g/cm 3.The FTIR analysis shows that the relative content of Si-O-Si group in the demineralized coal decreases,while the relative content of C-O group in phenol and ether increases.The aliphatic hydrocarbon enriches in the treated coal,and the length and degree of branching aliphatic side chains increase,while the polycondensation degree of aromatic ring has no effect.Float-and-sink method doesn’t change the initial reaction activation energy of all kinds of chemical bonds in the pyrolysis process.However,the aliphatic hydrocarbon enriches,the content of matter which bonds are easy to break increases,thus,the total mass loss in the pyrolysis process increases,and the tar yield increases.