神华煤直接液化残渣超临界溶剂萃取研究

利用甲苯、苯和乙醇三种溶剂在反应釜中对神华煤直接液化残渣进行了超临界溶剂萃取,考察了压力、温度、萃取时间、溶剂/残渣比等对萃取产物收率和重质液体萃取组成的影响。结果表明,以甲苯为溶剂进行萃取时,萃取时间对重质液体产率及HS和A收率的影响不大,而温度、压力以及溶剂/残渣质量比都会影响萃取产物的产率及组成。溶剂超临界萃取过程中,有其他组分向HS组分转化,提高了HS的收率。三种溶剂中,苯显示了和甲苯相似的萃取性能,而乙醇的萃取性能相比苯和甲苯则较差,但乙醇萃取得到的重质液体中轻质组分含量高于苯和甲苯。萃取过程中,残渣中的灰分和硫分主要富集至萃取残渣中。

Supercritical solvent extraction of direct liquefaction residue from Shenhua coal

Extraction of direct liquefaction residue from Shenhua coal with three solvents was investigated in a batch autoclave at supercritical conditions to clarify the impacts of pressure,temperature,and extraction time on the yields of heavy liquid and its compositions.It is found that when toluene is used as a solvent,extract time has no obvious effect on yield of heavy liquid,hexane soluble(HS) and asphaltene(A).Extract temperature,extract pressure and mass ratio of solvent to residue have significant effect on yield and composition of residue extract.During the supercritical solvent extraction of liquefaction residue,some other components are transformed into HS and this results in increasing yield of HS.Benzene shows similar extraction ability to toluene while ethanol is poor in dissolving heavy liquid.There are more light components in heavy liquid extracted by ethanol than those by benzene and toluene.Sulfur and ash are mainly enriched in extract residue during extraction process.