Preparation Of Ni-W/AP Catalyst And The Hydrogenation Of Thermal Dissolution Products Of Longquan Lignite

The targeted conversion of complex organic matter from coal into value-added chemicals and high-performance carbon materials is an ideal way to effectively utilize coal,and is also a major problem to be solved in the development of coal chemistry research and coal conversion technology development.High performance catalysts play an important role in this process.In this study,ammonium tungstate and nickel nitrate were used as tungsten sources and nickel sources respectively.A series of Ni-W/AP catalysts with different metal loads,W/AP and Ni/AP catalysts were simply and efficiently prepared by using the uniform volume impregnation method over the purified attapulgite.The catalyst preparation was compared with benzyl ether?OBMDB?and benzyl phenyl ether?BOB?as the research object for the preparation of catalysts are compared.As a result,it was found that the catalyst had the highest activity when the loading amount of WO₃ reached 20%.The optimum reaction temperatures for OBMDB and BOB over Ni-W/AP?Cat-20?are 220 ^oC and 240 ^oC,respectively,indicating that Cat-20 can effectively promote the>C-O-bridge cleavage.The ethanol-soluble portion?ESP?and the thermosoluble residue?TDR?of Longquan lignite?LL?were used as reactants for catalytic hydrocracking at 300 ^oC.The results showed that the three catalysts Ni/AP,W/AP and cat-20 had certain hydrolysis effect on TDR.The yield of liquid phase products obtained from the reaction is used to estimate the catalytic effect of three kinds of catalysts on TDR.The yields of liquid mixture dissolved by SP_TDR-Ni/APDR-Ni/AP and SP_TDR-W/AP were 4.62%and 7.45%,respectively,while the yield of SP_TDR-Cat-20 liquid product was much higher than that of the latter two,reaching 15.47%.It is further proved that Ni-W/AP?Cat-20?has better catalytic effect.The soluble components obtained from NCHC and CHC of TDR and ESP were analyzed by GC/MS,and the detected organic compounds were classified in detail according to their species and content.It was found that the kinds and contents of aromatic hydrocarbons and phenolic compounds detected in SP_TDR-Cat-20 and SP_ESP-Cat-20 were significantly higher than those in SP_TDR-NCHC and SP_ESP-NCHC.However,the contents of esters,ketones and ethers decreased significantly.In addition,abundant aromatic unsaturated compounds such as naphthalene were detected in both SP_TDR-Cat-20 and SP_ESP-Cat-20,indicating that Cat-20 not only selectively breaks C-C and C-O bridged bonds in lignite macromolecules,but also promote the generation of aromatics,phenols and other small molecular compounds,and has certain hydrogenation effect on some aromatic hydrocarbons in lignite macromolecule.In the GC/MS analysis of the catalytic products of ESP and TDR,a certain amount of sulfur-containing compound?SCOCs?and nitrogen-containing compound?NCOCs?were detected,indicating that Ni-W/AP?Cat-20?catalyst had a certain desulfurization and denitrification effect.Ni-W/AP can catalyze the pyrolysis of H₂ molecules in the solvent to generate active hydrogen atoms.Active hydrogen radicals can selectively attack the small active sites in condensed aromatic rings in ESP and TDR,resulting in the breaking of C-O and C_ar-C_alklk bridge bonds,and phenol compounds,polymethyl aromatic ring substituents and aromatic methyl compounds are formed.There are 28 figures,30 tables and 92 references in this thesis.