Fuzzy Inference System for Modeling of Zinc Removal Using Micellar-Enhanced Ultrafiltration

Discrete event computer simulation is one of the most widely used modeling tools for production systems. The major objective of this study is to develop a fuzzy rule-based model for the evaluation of micellar-enhanced ultrafiltration (MEUF) performance. In the current work, the foldover fractional factorial designs were applied as a screening experiment to determine all the influential factors affect Zn²⁺ rejection and permeate flux response. According to analysis of the variance (ANOVA) a three-screened significant factors, three-level full factorial designs (3 ^k ) was applied. Finally, a fuzzy model has been developed to predict and calculate the output variables. These mathematical models are found to be reliable predictive tools with an excellent accuracy with AARE ±1.08%, ±3.75%, in comparison with experimental values for permeate flux and rejection, respectively. It was observed that there is acceptable agreement between and fuzzy model results with experimental data.     

Micellar Enhanced Ultrafiltration as a Method of Removal of Chromium(III) Ions from Aqueous Solutions

This study was undertaken to check the possibility of using micellar enhanced ultrafiltration (MEUF) in the removal of chromium(III) ions from water systems. The influence of ion concentration in the feed, type of surfactant (SDS or Rofam 10), and the membrane material on separation efficiency were studied and discussed. The use of environmentally safer surfactants from renewable sources was proposed, that is, oxyethylated rape fatty acid methyl esters – trade name: Rofam 10. The results presented show the possibility of using MEUF as an effective method for removing chromium(III) ions from aqueous solutions, especially from solutions of low concentration.     

Simultaneous recovery of copper and surfactant by an electrolytic process from synthetic solution prepared to simulate a concentrate waste stream of a micellar-enhanced ultrafiltration process

Electroplating method was employed to recover copper and surfactant simultaneously from synthetic solutions prepared to simulate concentrated waste stream generated from micellar-enhanced ultrafiltration. Effects of surfactant and copper (II) concentrations, surfactant to copper (II) molar ratio (S/M), electroplating voltage and time, solution pH, and ionic strength on metal recovery and electrical current efficiency were investigated. Results show that at a fixed S/M ratio of 5, the first-order kinetic constant for Cu (II) removal by electroplating increases with decreasing SDS concentration. At fixed SDS concentration of 8.5 mM, increasing initial Cu (II) concentration increases both Cu (II) recovery and current efficiency. Electrolyte pH has profound effects on the metal recovery and current efficiency due to the difference in solution conductivity after pH adjustment and the extent of Cu (II) adsorption onto SDS at different pHs.     

Modeling and Performance Study of MEUF of Divalent Metal Ions in Aqueous Streams

Abstract

Modeling of micellar enhanced ultrafiltration (MEUF) was studied for the removal of Ni from aqueous phase by using sodium dodecyl sulphate for micellisation. Localized adsorption equilibrium model was used to predict the bound and unbound counter ions. The retentate concentration was predicted using localized adsorption equilibrium and a material balance model, and the experimental values are in close agreement with less than 1% deviations. Experimental values of the permeate flux were in close agreement with the predicted values obtained by resistances in the series model. An algorithm was developed for the prediction of the retentate concentration.     

胶束增强陶瓷膜处理镧离子废水的研究

将十二烷基硫酸钠(SDS)与孔径5nm的陶瓷膜结合,探索胶束增强陶瓷膜法处理镧离子废水的可行性.考察了SDS摩尔浓度、跨膜压差(TMP)、溶液pH值等因素对陶瓷膜过滤性能的影响.结果表明,随着SDS摩尔浓度的增大,陶瓷膜对La3+的截留率从70％增大到99.9％;当SDS摩尔浓度大于临界胶束浓度(CMC)后,膜对La3+的截留率略有降低,大约维持在95％～97％左右;膜通量则随SDS摩尔浓度增大先减小后增大,最后趋于65 L/(m2·h).随着TMP提高,膜通量基本呈线性关系增大,膜对SDS和La3+的截留率略增大.随着溶液pH的升高,渗透通量略有下降,膜对La3+和SDS的截留率均显著增加.采用体积浓度为0.5％的稀硝酸清洗污染的陶瓷膜,膜的纯水通量可恢复到95％以上,重复性好.     

Removal of Ni(II) ions from wastewater by micellar enhanced ultrafiltration using mixed surfactants

Ni(II) ions were removed from aqueous waste using micellar enhanced ultrafiltration (MEUF) with a mixture of surfactants. The surfactant mixture was the nonionic surfactant Tween 80 (TW80) mixed with the anionic surfactant sodium dodecyl sulfate (SDS) in different molar ratios ranging from 0.1–1.5. The operational variables of the MEUF process such as pH, applied pressure, surfactant to metal ion ratio and nonionic to ionic surfactant molar ratio (α) were evaluated. Rejection of Ni and TW80 was 99% and 98% respectively whereas that for SDS was 65%. The flux and all resistances (fouling resistance, resistance due to concentration polarization) were measured and calculated for entire range of α respectively. A calculated flux was found to be declined with time, which was mainly attributed to concentration polarization rather than resistance from membrane fouling.     

基于表面活性剂的膜分离技术

介绍了利用表面活性剂的液膜分离和超滤技术的分离原理,过程,ＳＡＡ品种与选择,展望,以及去除工业废水中有机物和重金属离子的实例。     

胶团强化超滤技术及其在废水处理中的应用研究进展

介绍了胶团强化超滤技术（Micelleenhanced uhrafiltration，MEUF）的原理、膜的选择、主要影响因素和存在的问题及改进方向，着重阐述了胶团强化超滤在废水处理方面的应用及研究进展。     

胶束强化超滤技术分离水溶液中有色金属离子的研究

胶束强化超滤是一种实现水溶液中小分子量物质分离的新技术.该技术利用表面活性剂胶束对金属离子的吸附作用,结合超滤工艺,进而达到去除Cd2 ,Cu2 ,Ni ,Pb2 ,Co2 ,Zn2 等有色金属离子的目的.介绍了胶束强化超滤技术分离水溶液中有色金属离子的研究现状,分析了该技术目前存在的问题以及今后的应用前景.     

Mathematical Modelling for Removal of Mixture of Heavy Metal Ions from Waste-Water Using Micellar Enhanced Ultrafiltration (MEUF) Process

The micellar enhanced ultrafiltration (MEUF) was studied for the removal of heavy metals using a mixture of non-ionic surfactant TWEEN-80 and anionic surfactant sodium dodecyl sulphate (SDS). The gel polarization model and resistance-in-series model were used to estimate the mass transfer coefficient (3 x 10-6 m/s) and the permeate flux. The total metal ion concentration was varied from 1 mM-4 mM and the corresponding effect of the trans-membrane pressure and limiting fluxes were studied. The modified resistance-in-series model was applied to these experimental data to correlate the flux with the feed concentration and applied pressure.