Impact And Evaluation Of Ionic Liquid On Thermal Dissolution And Depolymerization Of Yangchangwan Coal

Solvent extraction is one of the important methods to explore the characteristics of coal structure,preparation of ultra clean coal and the upgrading of coal.It is also of great significance of the efficient and clean conversion to coal resources.This paper mainly studied the normal temperature extraction of 9 kinds of organic solvents and the thermal dissolution and depolymerization of 7 kinds of ionic liquids(ILs)in Yangchangwan(YCW)coal of Ningdong Coal-mine Base in Ningxia Hui Autonomous Region.Dissociate the soluble fraction of the enriched coal to further to analyze its non-destructive or selective destructiveness.Analyze the composition and structure of low relative molecular weight products of ILs thermal dissolution and depolymerization to some extent reflect the partial structure information about YCW coal,and combine industrial analysis,elemental analysis,XRD,FT-IR,XPS,13CNMR,etc.used physical constants statistical structure analysis results to construct a YCW coal microscopic macromolecular structure model and perform quantum chemical calculations.This study aims to explore the direct separation and enrichment of coal under mild conditions.An effective way to convert organic components in each component or to transform coal in a specific direction,and to explore feasible solutions for further synthesizing high-value-added fine chemicals by using the directly-separated components from coal as raw materials to fill the microstructure and reaction of Ningdong coal.Blank of sexual research.Research shows:the extraction yield of YCW coal in the selected 9 solvents follows the extraction rule of DMSO>NMP>DMF>ALKY>MET>CYC>DMK>PET>CYH,and the extraction yield is also contained nitrogen,alcohols,ketones The order of hydrocarbons is decreasing.It was also found that for the same type of solvent,the higher the polarization,the higher the extraction yield.Compared with DMF and NMP,DMSO can dissolve more dissolved ILs,and the yield of DMSO extraction of YCW coal vitrinite group is higher.The extraction yield of YCW coal vitrinite group of different ILs thermal dissolving and depolymerization is in DMSO.Follow these rules:[Bmim][CF3SO3]>[Bmim][Cl]>[Emim][AC]>[Bmim][AC]>[Emim][BF4]>[Bmim][BF4]>[HOEtmim][BF4].Thermal dissociation depolymerization is not only related to the volume of ILs cations,but also related to the number of nuclear charge of anions.The recoveries of ILs were all above 90%.The spectra of recycled ILs and fresh ionic liquids FT-IR had almost no change except for hydrogen bonds.The recovery yield of the recycled thermal dissolution and depolymerization of the ILs was almost not reduced.It also showed that the ILs were not contaminated during the thermal dissociation process and the back extraction recovery process,and they maintained good performance.The FT-IR spectrum of the extracted product was analyzed,indicating that the extracted product can basically represent the overall structure of YCW coal vitrine.The results of GC/MS analysis of conventional organic solvent extraction products and ILs the thermal dissolution and depolymerization products showed that the contents of the extracted substances of different conventional solvents and different ILs on YCW coal were different and were roughly divided into the following categories:aliphatic hydrocarbons,aromatics Hydrocarbons,alcohol ethers,esters,ketones,phenols,nitrogen-containing compounds,carbonic acids,and other compounds.The peak order linear alkanes precede the branched alkanes and C7～C44 appear.The aromatics in the extract contain benzene,naphthalene,anthracene,phenanthrene,and fluorine all appeared and the content was mainly benzene,naphthalene and anthracene.By enriching the Ningdong coal Vitrinite group,and using traditional analysis of industry,elemental analysis and XRD,FT-IR,XPS,13CNMR and other characterization methods combined with conventional organic solvent extraction and ILs thermal dissolution depolymerization products GC/Ms.analysis Based on the group structure,the aromatic structure was basically distributed,and the YCW coal vitrine XBP was calculated to be 0.23,and a YCW coal macromolecule model was established.Based on the model’s multiple calibrations,annealing calculations and geometry optimization,a reasonable YCW coal macromolecular geometry is obtained.The full-electronic quantum chemical calculations have been used for the rational coal macromolecular structure,and the FT-IR and 13CNMR simulation maps of the coal molecular structure have been obtained.At the same time,the peak shape and peak intensity has been compared with the YCW coal experimental spectrum.A good correspondence has been established.Therefore,the rationality of the constructed coal molecular structure was verified.