煤热解过程中含硫气体的释放特征

Release of sulfur containing gases during coal pyrolysis

利用热解炉-高分辨飞行时间质谱联用仪和热解炉-同步辐射光电离飞行时间质谱仪检测不同含硫量的煤IBC105和C22650在热解过程中释放的8种含硫气体,并对这8种含硫气体的释放规律进行了分析.实验结果表明,在200℃—400℃的热解区间内含硫气体释放相对较多,表明硫元素大部分是以有机态的形式在煤中赋存,而且芳香硫相对于脂肪硫含量较多;同时含硫量较高的煤IBC105中噻吩硫的热解释放量,较煤C22650多;由于煤中芳香性有机物的裂解多以苄基的形式出现,因此在两种煤中二苄基硫醚释放量都较噻吩或者苯并噻吩多.

Two kinds of sulfur-bounding coals,IBC105 and C22650,were thermally pyrolysed to investigate the release pattern of the specified eight sulfur-containing gases.The release curve of these step-wise emission gases were monitored by pyrolysis furnace high resolution Time-of-flight mass spectrometry（PY-TOF-MS） and pyrolysis furnace synchrotron VUV photoionization mass spectrometry in high vacuum state（PY-SVUV-PIMS）.The experimental result shows that most of the sulfur-containing gases were released in the defined temperature range of 200 ℃—400 ℃,which indicated that most of sulfur in the both coals belonged to organic sulfur.And the content of aryl sulfide was more abundant than aliphatic sulfide.In addition,the release amount of thiophene sulfide in the high-sulphur coal（i.e.IBC105） was higher than the mid-sulphur coal（i.e.C22650）.As expected in the common cases that benzyl sulfide is the predominant pyrolysis product of aromatic organic compounds in coal,the release amount of dibenzyl sulfide in the both coals was also higher than thiophene or dibenzothiophene.