Researching Extraction And Separation Of Common Drugs And Acid Ions In Water By The New Hydrophobic Deep Eutectic Solvents Of Aromatic Acids

Deep eutectic solvents as a novel green solvent,it has the advantages of low vapor pressure,less atmospheric pollution,the wide liquid temperature range,low melting point good conductivity and thermal stability.In addition,it also has the advantages of easy availability of raw materials,simple and green preparation,low price and no need to further purify.Therefore,it can replace the traditional volatile organic solvents and ionic liquids that are difficult to prepare,purify and expensive.Thus it can be used in the fields of synthesis,electrochemistry,extraction and separation.At present,the work in this field is mainly concentrated in hydrophilic deep eutectic solvents,but less research on hydrophobic deep eutectic solvents.However,hydrophobic deep eutectic solvents can be used in aqueous phase,which greatly broadens the application range of deep eutectic solvents,especially for the treatment of polluted water bodies.In view of the excellent properties of hydrophobic and hypoeutectic solvents,a batch of hydrophobic and hypoeutectic solvents of aromatic acids have been successfully prepared by selecting suitable quaternary ammonium salts and aromatic acids as raw materials.The density,viscosity,melting point(or glass state transition temperature)and thermal decomposition temperature of these solvents have been determined,and their structures have been characterized by nuclear magnetic hydrogen spectrum and infrared spectrum.On the basis of this,the synthetic hydrophobic eutectic solvent is used for the extraction and separation of the two large groups of environmental pollutants of the water body and the inorganic acid radical ion,in which the medicine selects the paracetamol,metronidazole,methymercaptoimidazole,titriazole and amphenyl sulfone,and the acid radical ion selects dichromate,permanganate and orthophosphate.The effects of pollutant concentration,volume,temperature,pH value,type of low eutectic solvent,inorganic salt and other factors on extraction efficiency were systematically studied.The extraction efficiency of paracetamol,metronidazole,methimidazole,thiazole and amphenylsulfone was 98.65%,71.80%,91.72%,100% and 100% under optimal conditions,respectively.The extraction efficiency of dichromate,permanganate and orthophosphate was 100%,100% and 63.05% respectively.According to the experimental results,hydrophobic aromatic acid and deep eutectic solvents have a good extraction effect on the five drugs and three kinds of acid ions.In addition,in order to verify the synthesis of deep eutectic solvent applied value in natural water bodies,The authors respectively from the Dan river,Qin river,Wei river and the Communist canal,and obtained the actual water samples of four surface water,and use it to the standard extraction of metronidazole,dapsone,dichromate and orthophosphate.It is shown that the extraction efficiency of standardized surface water sample is roughly equivalent to that of pure water solution,that is,in the actual polluted surface water sample,the newly prepared deep eutectic solvents have a good application prospect.