The Research Of Repeating Acidification UF And Reuse SDS Micelles From MEUF

The surfactant has a wide range of applications in daily life and production,however it may produce great harm to human,animals and plants and also pollute the environment when misconduct the surfactant.A new method called Micellar enhanced ultrafiltration(MEUF)which is based on the surfactant of the unique characteristic of parental molecular structure.Micellar enhanced ultrafiltration can remove low concentration heavy metals and organic pollutants in the water.It is a technology that combined ultrafiltration with surfactant.Compare with the traditional ultrafiltration MEUF has many advantages.Such as the lessen cost,more effective removal rate of metal ions.Meanwhile,compared to the method of distillation,adsorption,extraction and other methods the MEUF has low energy consumption.But the concentrated solution from MEUF contains high concentration of heavy metal ions and surfactant.So it must be need a further processing for recovering and recycling surfactant,which can reduce the consumption of surfactant and secondary pollution.The Sodium dodecyl sulfate(SDS)is investigated as a surfactant for heavy metal ion removal via micellar enhanced ultrafiltration(MEUF).It is important to recover and reuse surfactant SDS from the MEUF retentate stream due to the high demand of surfactant.Repeated acidification is a new way to recover and reuse surfactant.The effects of pH,the initial surfactant concentration of simulated MEUF retentate solution,the concentrated solution volume by acidification ultrafiltration,and the acidification times on SDS recovery and reuse were studied.At pH 1.0,the heavy metal Cd2+was effectively separated from the surfactant micelles,and the SDS had the highest recovery rate.Additionally,the rate of the removal metal ions by reused SDS micelles was higher than 85.00%at pH 1.0.When the initial SDS concentration of the simulated MEUF retentate solution was 2.0 CMC,the efficiency of SDS recovery and reuse was better than of that at 1.0 CMC.The smaller the acidification ultrafiltration concentrated solution volume was,the higher the rates of separation rate and removal rate by reused SDS of metal ions were.In addition,the particle size of SDS micelles after acidification ultrafiltration was measured,and the size was much larger than that of ultrafiltration membrane pore size.SDS can be repeatedly used when the concentration achieves its CMC.