| If the petroleum residue can directly transfer hydrogen with the coal macromolecule in the solvent,then the conversion rate of coal can be improved due to the low H/C atomic ratio of coal but high of petroleum residue.Based on this theory,this paper conducted experiments on the feasibility of coal and oilcoprocessing.In the experiments,different mass contents of vacuum residue and Yanchang atmospheric residue?YAR?were added into Xinjiang Longquan Lignite extraction residue?LL?to investigate the synergistic effect of coal and oil coprocessing,researching the changesin conversion rate of Longquan coal to analysethe positive synergistic effect between coal and petroleum residue.As a result,the synergistic effect was most significant when adding 10%of YAR.The soluble portion obtained by hot meltof Longquan coal(SPLL)and the soluble portion obtained by hot meltof Longquan coal and 10%YAR(SPLL+YAR)were analysed by GC/MS,and the results showed that SPLL contains more oxygen-containing compounds,whichwas consistent with high oxygen content of lignite and the elemental analysis results.SPLLL contains less types and contents of paraffin,naphthenic and aromatic compounds,but the addition of YAR promoted the increase of the type and content of such compoundsin SPLL+YAR,especially for aromatic compounds.Meanwhile,the experimental conditions of residue amount,pressure,temperature and time in coal and oil coprocessing were explored,and the optimal experimental conditionswere determined at 10%atmospheric residue,2 MPa nitrogen,320 oC and 4 h.The supported super acid solid catalyst TFMSA/HZSM-5 was prepared,andthe characterization results showed that trifluoromethanesulfonic acid was successfully loaded onto the support,and the prepared catalyst had strong acidity.Phenylbenzyl ether and dibenzyl ether?OBMDB?were chosen as lignite model compounds to investigate the mechanism of catalytic cracking.TFMSA/HZSM-5 releases protons to the oxygen atom of the ether bridge,causing the cleavage of Calk–O bridge bonds,and the product ions capture in solvent hexane to achieve stablility,and the oxygen lone pair electron in the ethanol attacks pyrolysis ions to form a protonated intermediate,which is extremely unstable and then releases protons to a stable state.It was found that there was no significant change in atmospheric residue before and after catalysis.In addition,a certain amount of YAR was added to the solvent to catalytically crack OBMDB at the same conditions,and methylcyclohexane was present in the catalytic productof OBMDB.Compared with SPYAR,the-CH3 and-CH stretching vibration absorption peak abundance of cycloalkane in SPCC-OBMDB+YAR decreased,and theunsaturationin SPCC-OBMDB+YARC-OBMDB+YAR increased significantly.It can be seen that the YAR may contain partial hydrogenated arenes,which have a certain role in hydrogen supply.The conversion rate of Longquan lignite in catalytic conversion was significantly higher than that in non-catalytic conversion,indicating that the catalyst TFMSA/HZSM-5 can effectively promote the catalytic cracking of coal,and the conversion rate is higher than the former two after adding 10%YAR.Under the catalysis of TFMSA/HZSM-5,the types and contents of arenes in SPCC-LL are greatly increased,indicating that the catalyst can promote the formation of arenes.Meanwhile,the types and contents of ketones and phenolic compounds have also increased greatly,indicating that the catalyst can effectively promote the cleavage of carbonyl-containing C–O bridge bonds and the release of phenolic compounds.The types and contents of naphthenes in SPCC-LL+YAR of coal and oil co-catalyst system increased significantly,which may be caused by the hydrogen supply of hydrogenated arenes in YAR.In addition,the types and contents of arenes also increased significantly,possibly due to more fused arenes in YAR leading to more arenes hot melt from coalat high temperature and pressure,according to the principle of similar compatibility.There are 34 figures,7 tables and 80 references in this thesis. |
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