Experiment Research Of Dissolution Of Anthracene And Extraction Of The Mixture Of Anthracene Phenanthrene By Supercritical Ethanol

Coal tar as a complex liquid product composed of aromatic compounds is obtained in process of high temperature carbonization of coal,which contains about ten thousands components.It is about five hundred components have been separated from coal tar,which accounted for about 55% in the total coal tar.A lot of high value products are separated from coal tar,and some of those even cannot be replaced by petrochemical industry product.Thus,the investigation of high efficiency and low pollution new technology of coal tar deep processing can not only be reasonable utilization of valuable coal tar and reduce dependence on petroleum,but also has wide application prospect and good economic potential.Anthracene and phenanthrene are significant ingredient content in coal tar,which have important applications on the dyes,pesticide production and organic synthesis intermediates.It is necessary to investigate and innovate its separation technology as current processing methods is still existing some deficiencies.Supercritical fluid extraction technology is a new type of efficient and environmental separation technology,which has advantages of simple process,environmental protection and operation stability etc.In recent years,many people pay attention to extraction important chemical products from coal tar by supercritical fluid extraction technology.Ethanol was utilized as solvent in the experiment through setting different temperature and pressure to explore supercritical ethanol dissolving anthracene.The extraction rule of anthracene and phenanthrene were investigated under different temperature and pressure extraction.Pentane and methanol were used as entrainer to explore the impact of different entrainers on anthracene and phenanthrene extraction rate.The response surface optimization method was used to obtain the best condition of supercritical ethanol extraction of anthracene and phenanthrene.The results showed that the best dissolved ratio of anthracene was 63% at 270?,13 MPa.Extraction rules of anthracene and phenanthrene was similar,and the best extraction rate of anthracene and phenanthrene were 56.7% and 61.2% at thetemperature and pressure of 275? and 12.6MPa.Pentane and methanol were added as entrainer,and methanol had better extraction of anthracene and phenanthrene.Finally,response surface optimization method was applied to obtain the best extraction conditions at 273?,and the amount of ethanol and methanol were 66 ml and 10.3ml,and the extraction rate of anthracene and phenanthrene were 62.3% and 68.9%respectively.Optimum condition was used to extract actual industry coal tar,the content of anthracene and phenanthrene in coal tar were twice as high as the premise,and the result demonstrated that supercritical ethanol extraction enrichment was obvious.