Analysis On Fast Pyrolysis Characteristics Of Low Temperature Coal Tar

As an important intermediate product in the process of coal chemical industry,coal tar is a complex structure.At present,there are few studies on the molecular composition of coal tar and the rapid pyrolysis modification of coal tar at home and abroad.Therefore,in this paper,a low temperature coal tar in Xinjiang is taken as the research object,and its composition and pyrolysis characteristics are studied by different experiments.First,the full two-dimensional gas chromatography-time of flight mass spectrometer(GC x GC-TOF/MS)was used to detect and characterize the material contained in coal tar.2231 compounds contained in the sample were detected and further classified,and the percentage content of several kinds of compounds in coal tar and the percentage of all kinds of compounds were summed up.Secondly,the pyrolysis characteristics of low temperature coal tar were analyzed by fast pyrolysis gas chromatography / time of flight mass spectrometry(Py-GC/TOF-MS).By comparing the changes of alkanes,naphthenic hydrocarbons / alkene / alkynes,aromatic hydrocarbons,phenolic alcohols,oxygen containing heterocyclic compounds,ketones,nitrogen and sulfur compounds in volatile products,coal was summed up.The pyrolysis characteristics of tar compounds under different reaction conditions were studied.At last,a small fixed fluidized bed was used to investigate the cracking modification of coal tar in different active component catalysts,different reaction temperatures and different oil ratio conditions.By analyzing the fast pyrolysis products of low temperature coal tar under different properties,it was found that the calcium aluminate catalyst was used,because the reaction mechanism was different.Compared with the FCC catalyst,the low carbon olefin selectivity is higher than the other catalysts,and it has a better industrial application prospect.Through the pyrolysis experiment of different reaction temperature and agent oil ratio,it isfound that the light oil yield is higher at 575?to 600?,and the light oil is collected when the oil ratio is 8:1.The rate is high,which is suitable for catalytic pyrolysis.