Abstract
Immediate use of activated carbon incorporated polysulfone membrane application for dye separation was reported in this work. Dimethylformamide (DMF) was used as the solvent for the membrane preparation. The membrane thus prepared were characterized in terms of surface morphology, ATR-FTIR, AFM, experimental results as membrane performance. The resultant nanofiltration (NF) membranes were tested with Congo red dye concentration 200 mg/L. The water permeability was found to be considerably higher than that reported in literature. Experimental results show that the real rejection of the Congo red is 99.57% over the transmembrane pressure 100 psi using 30% activated carbon incorporated membrane. Prepared NF membranes shows the corresponding permeates fluxes were 40 Lm-2h-1 to 82 Lm-2h-1 with different activated carbon percentage incorporated in polysulfone membrane. The present study demonstrated that dye rejection enhanced NF may be a feasible method for the dye wastewater treatment. The overall observations thus indicated that toxic residual dyes can be appreciably separated from the membrane technology, provided that the accompanying polymeric membrane, activated carbon as binding agents and the process parameter levels are astutely selected.
Address
(1) Pravin G. Ingole, Hyung Keun Lee:
Climate Change Research Division, Korea Institute of Energy Research, 71-2 Jang-dong, Yuseong-gu, Daejeon 305343, South Korea; (2) Sandesh Y. Sawant, Moo Hwan Cho:
School of Chemical Engineering, Yeungnam University, Gyeongsan-si, Gyeongbuk 712- 749, South Korea; (3) Neha P. Ingole:
Department of Biology, Chungnam National University, Daejeon 305764, South Korea; (4) Radheshyam R. Pawar:
Department of Energy and Environment Convergence Technology, Catholic Kwandong University, Gangneung 210701, South Korea; (5) Hari C. Bajaj, Kripal Singh:
CSIR-Central Salt & Marine Chemicals Research Institute, G.B. Marg, Bhavnagar 364002, Gujarat, India.
Abstract
Mesoporous MCM-41 was deposited on an inexpensive disk shaped ceramic support through hydrothermal technique for ultrafiltration of Fe3+ from aqueous solution. The ceramic support was fabricated using uni-axial compaction technique followed by sintering at 950°C. The characteristics of MCM-41 powder as well as the composite membrane were examined by X-ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscope (FESEM), porosity and pure water permeation test. The XRD result revealed the good crystallinity and well-resolved hexagonally arranged pore geometry of MCM-41. TGA profile of synthesized MCM-41 zeolite displayed the three different stepwise mechanisms for the removal of organic template. The formation of MCM-41 on the porous support was verified by FESEM analysis. The characterization results clearly indicated that the accumulation of MCM-41 by repeated coating on the ceramic disk directs to reduce the porosity and pore size from 47% to 23% and 1.0 to 0.173 μm, respectively. Moreover, the potential of the fabricated MCM-41 membrane was investigated by ultrafiltration of Fe3+ from aqueous stream at various influencing parameters such as applied pressure, initial feed concentration and pH of solution. The maximum rejection 85% was obtained at applied pressure of 276 kPa and the initial feed concentration of 250 ppm at pH 2.
Key Words
ultrafiltration; FeCl3; zeolite membrane; MCM-41; hydrothermal
Address
(1) Ashim Kumar Basumatary, R. Vinoth Kumar, G. Pugazhenthi:
Department of Chemical Engineering, Indian Institute Technology Guwahati, Guwahati 781039, Assam, India; (2) Kannan Pakshirajan:
Department of Biosciences and Bioengineering,Indian Institute Technology Guwahati, Guwahati 781039, Assam, India.
Abstract
The effect of ZnO on cellulose acetate in the removal of benzophenone-3 (BP-3) was investigated. The benzophenone-3 (BP-3) which is an endocrine disrupting chemical (EDC) was completely removed (100%) from the drinking water using Cellulose Acetate (CA) and zinc oxide (ZnO) composite membranes. The membranes were prepared by DIPS method and the filtration experiments were conducted by dead end filtration unit. The macrostructure of the membrane were studied by ATR-IR and XRD Spectra's. Atomic force microscopy (AFM) and Scanning electron microscopy (SEM) were used to study the micro properties of the membranes. The laboratory experiments such as water uptake study and pure water flux performed to confirm the increasing hydrophilicity. The enhancing hydrophilicity was confirmed with respect to higher the concentration of nanoparticles. Evaluation of BP-3 removal was carried in different experimental conditions, such as, different Trans membrane pressure and different concentration of feed. The membrane with low pressure showed better performance by rejecting 100% of BP-3. However, 1 ppm, 3 ppm and 6 ppm of feed solution was used and among them 3ppm of feed solution gives 100% rejection. The ZnO nanoparticales enhances the performance of CA membrane by showing maximum rejection.
Abstract
Laboratory-scale experiments were carried out to investigate the adsorption equilibrium, the adsorption kinetics and facilitated transport of two cationic dyes (Methylene Blue (MB) and Rhodamine B (RB)) on Polymer Inclusion Membrane (D2EHPA-PIM). Different adsorption isotherms (Freundlich, Langmuir and Temkin models) as well as kinetics models indicated that the adsorption process is spontaneous and exothermic. Under the optimal conditions, the adsorption removal efficiencies reach about 93% and 97% for MB and RB respectively. Different extraction values by D2EHPA-PIM were obtained for the two cationic dyes: MB is weakly extracted at pH 2.0 (E% = 18.7%) whilst E% = 82.4% was observed for RB at the same pH. This difference was exploited in a mixture containg both the 2 cationic dyes for the selective extraction of RB at pH 2. Desorption of both dyes was achieved from the membrane by using acidic aqueous solutions and desorption ratio up to 90% was obtained. The formulas of the extracted complexes by the PIMs were, determined by the method of slopes. The dyes transport was elucidated using mass transfer analysis where in it found relatively high values of the initial flux (J0) as 41.57 and 18.74
Key Words
Polymer Inclusion Membrane (PIM); D2EHPA; extraction; cationic dyes; kinetics; equilibrium; facilitated transport
Address
Laboratoire des Procédés Membranaires et des Techniques de Séparation et de Récuperation (L PMTSR), Faculté de Technologie-Université de Bejaia, DZ -06000, Bejaia - Algeria.
Abstract
As a novel hydrophobic monomer, polytetrahydrofuran diacrylate (PTMGDA) was synthesized by the esterification reaction between polyethylene tetrahydrofuran (PTMG) and acryloyl chloride (AC). In situ free radical polymerization reaction method was utilized to fabricate poly (vinylidene fluoride) (PVDF)-PTMGDApoly(ethylene oxide) dimethacrylate (PEGMA) ulrafiltration (UF) membranes. The performances of PVDFPTMGDA- PEGMA UF membranes in terms of morphologies, mechanical properties, separation properties and hydrophilicities were investigated. The introduction of the PTMGDA-PEGMA dopants not only increased the membranes' pure water flux, but also improved their mechanical properties and the dynamic contact angles. The addition of the PTMGDA/PEGMA dopants led to the formation of the finger-like structure in the membrane bulk. With the increase concentration of PTMGDA/PEGMA dopants, the porosity and the mean effective pore size increased. Those performances were coincide with the physicochemical properties of the casting solutions.
Key Words
PVDF-PTMGDA-PEGMA membrane; PTMGDA-PEGMA dopants; in situ free radical polymerization; hydrophilicity
Address
(1) Gui-E. Chen, Hui-Hong Huang, Wen-Zhi Wu, Li Sun, Yan-Jun Liu:
School of Chemical and Environmental Engineering, Shanghai Institute of Technology, 100 Haiquan Road, Shanghai 201418, China; (2) Zhen-Liang Xu, Ping-Yun Zhang:
State Key Laboratory of Chemical Engineering, Membrane Science and Engineering R&D Lab, Chemical Engineering Research Center, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
Abstract
Heavy metal contamination has attracted considerable attention during recent decades due to the potential risk brought about for human beings and the environment. Several adsorbent materials are utilized for the purification of contaminated water resources among which chitosan is considered as an appropriate alternative. Copper is a heavy metal contaminants found in several industrial wastewaters and its adsorption on porous and macroporous chitosan membranes is investigated in this study. Membranes are prepared by phase inversion and particulate leaching method and their morphology is characterized using SEM analysis. Batch adsorption experiments are performed and it is found that copper adsorption on macroporous chitosan membrane is higher than porous membrane. The iso-steric heat of adsorption was determined by analyzing the variations of temperature to investigate its effect on adsorption characteristics of macroporous chitosan membranes. Furthermore, desorption experiments were studied using NaCl and EDTA as eluants. The mechanism of copper adsorption was also investigated using XPS spectroscopy which confirms simultaneous occurrence of chelation and electrostatic adsorption mechanisms.
Key Words
macroporous chitosan membrane; adsorption; desorption; isotherm; XPS study
Address
(1) Azadeh Ghaee:
Department of Life Science Engineering, Faculty of New Sciences & Technologies, University of Tehran, P.O. Box 14399-55941, Tehran, Iran; (2) Mohammad Mahdi Zerafat:
Faculty of Advanced Technologies, Nano Chemical Engineering Department, Shiraz University, Shiraz, Iran.
