Research On Treatment Of 1, 2-Dichloroethane Wastewater By Method Of Micellar-Enhanced Ultrafiltration

Micellar-enhanced ultrafiltration(MEUF) is a new purification technique combining surfactants and ultrafiltration membranes, and can be used to remove organic matter and metal ions from wastewater.In this article the solubilization rate of surfactants on dichloroethane(DCE) was tested by gas chromatography(GC). The results indicate that the sequence of solubilization rate in turn is nonionic surfactants, cationic surfactants and anionic surfactants. The experiments of solubilization coefficient(Ki) show that among three kinds of cationic surfactants the sequence of solubilization rate in turn is cetyltrimethyl ammonium chloride (CTACl), cetyltrimethyl ammonium bromide (CTABr) and cetyltrimethyl pyridine bromide(CPBr). In order to improve the solubilization rate of surfactants on DCE, anionic surfactants, salts and polymers were added to cationic surfactants. The results demonstrate that this method does not improve the solubilization rate of surfactants on DCE.The results of light scatter experiment and nuclear magnetic resonance spectroscopy(NMR) not only prove DCE can be solubilized by surfactants, but also indicate DCE is preferential solubilized both in the palisade and in center of the micelle core.The types and concentration of surfactants, the vibrating time and the stabling time were investigated by othogonal test which demonstrate the best operatinol conditions are the concentration of nonionic surfactants is 30mmol/l, the vibrating time is 1h and no stabling time.At these conditions, the solubilization of DCE can reach 34.32%. In the above conditions and the pressure of 0.175MPa,the membrane of polyacrylonitrile and polysulfone were used to ultrafiltrate wastewater, thepermeation flux is 0.2310-10m3/(m2·s·Pa) and the rejection of DCE in the water could reach 90.04%. Finally the solution of NH4Br was added to the concentration fluid ,when precipitation appears,we use filter paper to filter the concentration fluid, the remaining materials after filtration were incinerated or evaporated, dried and reused.The MEUF has such a few advantages: being simply operated, being easily industrialized, being suitable to remove organic matter and metal ions with lower molecular weight and concentration from wastewater independently or simultaneously. So the environmental profit of the MEUF is highly significant. In the meantime, in comparison with the method of adsorption, distillation and extraction, the MEUF also has such several advantages: being no phase variation, the disposed wastewater can be directly reused, valuable organic matter or heavy metals can be recovered and reused from concentrating fluid with certain measures. Therefore, the MEUF has significantly economic profit and considerably practical value.