Research On The Matching Regularity Between The Cracking Of Coal And The Hydrogen Supply Of Solvent In Direct Coal Liquefaction

As a clean utilization technology of coal,direct coal liquefaction can effectively alleviate the problems related to energy security and economic development caused by the contradiction between oil supply and demand.However,the products obtained by the traditional direct coal liquefaction process not only contain small molecular products such as oil and gas,but also contain asphaltenes,pre-asphaltenes,residues,etc.The presence of these substances affects the performance of direct coal liquefaction,which is mainly caused by the low degree of matching between the cracking of coal and the hydrogen supply of hydrogen supply solvent.The chemical bond structure in coal determines the difficulty of its cracking.Therefore,the ether model compounds and arylalkane model compounds were used as the representatives of weak and strong bonds in coal.Using the method of tetralin hydrogenolysis of model compounds,the matching regularity between the cracking of coal and the hydrogen supply of hydrogen supply solvent was studied,and the possible generation path of heavy products was proposed.The conclusions of this article are shown as follows.(1)Through the tetralin hydrogenolysis of ether model compounds,benzyl phenyl ether(BPE)was screened out as a suitable research object.The effects of tetralin concentration,reaction temperature,reaction time,catalyst and hydrogen on the matching degree between the cracking of BPE and the hydrogen supply of tetralin were investigated.It has been found that increasing the concentration of tetralin is not conducive to the increase in the conversion of tetralin and the yield of naphthalene.The relative content of toluene in the BPE derivative first increased and then decreased,and the degree of matching between the cracking of the model compound and the hydrogen supply of the solvent first increased and then decreased.As the temperature increased,the yield of tetralin dehydrogenation product naphthalene decreased.The relative content of toluene first increased and then decreased,and the degree of matching between the cracking of the model compound and the hydrogen supply of the solvent first increased and then decreased.Extending the reaction time promoted the conversion of tetralin to produce more naphthalene,the relative content of toluene first increased and then decreased,and the matching degree between the cracking of BPE and the hydrogen supply of tetralin first increased and then decreased.The Fe1-XS catalyst is beneficial to improve the matching degree between the cracking of the model compound and the hydrogen supply of the hydrogen supply solvent.The effect of hydrogen on the matching degree of cracking and hydrogen supply is affected by temperature.(2)Diphenylethane(DPE)was selected as the most suitable substance for studying arylalkane model compounds through hydrogenolysis reaction.In addition,the effects of tetralin concentration,reaction temperature,reaction time,catalyst and hydrogen on the matching degree between the cracking of DPE and the hydrogen supply of tetralin were investigated.The results showed that as the concentration of tetralin increased,both the conversion of tetralin and the yield of naphthalene decreased.The yield of toluene in DPE derivatives has been reduced,and the degree of matching between the cracking of the model compound and the hydrogen supply of the solvent has also been reduced.Increasing the temperature promotes the production of naphthalene and toluene,which is conducive to the improvement of the matching degree between the cracking of DPE and the hydrogen supply of tetralin.Extending the reaction time can promote the conversion of tetralin and the cracking of DPE,thereby improving the matching degree between the cracking of arylalkane compounds and the hydrogen supply of the solvent.The Fe1-XS catalyst is beneficial to improve the matching degree between the cracking of the arylalkane compounds and the hydrogen supply from the solvent.The addition of hydrogen is beneficial to improve the matching degree between the cracking of the arylalkane compounds and the hydrogen supply from the solvent.