A novel positively charged membrane based on polyamide thin-film composite made by cross-linking for nanofiltration

2015 ◽  
Vol 73 (4) ◽  
pp. 776-789 ◽  
Author(s):  
Ahmad Akbari ◽  
Zahra Fakharshakeri ◽  
Sayed Majid Mojallali Rostami
Keyword(s):  
Interfacial Polymerization ◽  
Membrane Surface ◽  
Water Flux ◽  
Feed Solution ◽  
Contact Angles ◽  
Cross Linking ◽  
Cross Sectional ◽  
Charged Membrane ◽  
Trimesoyl Chloride ◽  
Positively Charged

In this paper, a novel positively charged membrane was prepared through interfacial polymerization technique between polyethyleneimine in aqueous phase and trimesoyl chloride in organic phase. Next, cross-linking of polyamide (PA) layer using ρ-xylylene dichloride (XDC) and glutaraldehyde (GA) was studied. The influences of cross-linking concentrations on the separation and permeation performance of membrane were also investigated. Membranes were characterized in terms of their chemical structure, the cross-sectional and surface morphologies, contact angles, molecular weight cut-off (MWCO) and effect of pH feed solution. The salt rejection sequence of CaCl2 >NaCl > Na2SO4 showed a positive charge at the membrane surface after cross-linking reaction. The MWCO of primary PA membrane decreased from 1,135 to 775 and 885 Da for XDC and GA, respectively. XDC membrane shows highest CaCl2 divalent cationic rejection (95.5%) and lowest water flux (21.1 L/m2.h). This study illustrates a promising method for fabrication of positively charged membrane in cation separation.

scholarly journals Enrichment of lithium from salt lake brine by forward osmosis

2018 ◽  
Vol 5 (10) ◽  
pp. 180965 ◽  
Author(s):  
Jinli Li ◽  
Min Wang ◽  
Youjing Zhao ◽  
Hongjun Yang ◽  
Yuan Zhong
Keyword(s):  
Salt Lake ◽  
Membrane Surface ◽  
Water Flux ◽  
Forward Osmosis ◽  
Feed Solution ◽  
Quantitative Structure Activity Relationship ◽  
Contact Angles ◽  
Draw Solution ◽  
Concentrating Solutions ◽  
Relationship Of

Forward osmosis (FO) is a concentration process based on the natural phenomena of osmosis. It is considered a breakthrough technology that can be potentially used for concentrating solutions and suspensions. The diluted nature of brine restricts the treatment technologies that can be applied. Then, brine concentration by FO could represent a new emerging technology enabling the application of a wider range of treatment alternatives. The performance of concentrated brine depending upon FO membranes was studied at normal temperature and pressure in this research. Cellulose triacetates on radio-frequency-weldable non-woven support (CTA-NW) and a thin-film composite with embedded polyester screen support (TFC-ES) were compared; and their orientations were considered. The brine was from Chaerhan Salt Lake after extracting potassium as the feed solution, NaCl solution or MgCl 2 solution as the draw solution. The results indicated that CTA-NW exhibited better concentration performance than TFC-ES, while the water fluxes of the two membranes were exactly the opposite. In the case of CTA-NW in active layer facing feed solution orientation with MgCl 2 as the draw solution, the concentration factor of Li + was nearly 3.0. Quantitative structure–activity relationship of FO membranes and concentration characteristics was correlated, based on results of SEM, FTIR and contact angles studies. The concentration performance could be mainly attributed to the porosity and the thickness of FO membranes; while the water flux was dependent on the hydrophily of FO membrane surface.

scholarly journals ZnO Microfiltration Membranes for Desalination by a Vacuum Flow-Through Evaporation Method

Membranes ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 156 ◽  
Author(s):  
Shailesh Dangwal ◽  
Ruochen Liu ◽  
Lyndon D. Bastatas ◽  
Elena Echeverria ◽  
Chengqian Huang ◽  
...  
Keyword(s):  
Membrane Fouling ◽  
Membrane Surface ◽  
Water Flux ◽  
Atomic Layer ◽  
Rejection Rate ◽  
Contact Angles ◽  
Transfer Resistance ◽  
Membrane Pore ◽  
Evaporation Method ◽  
Flow Through

ZnO was deposited on macroporous α-alumina membranes via atomic layer deposition (ALD) to improve water flux by increasing their hydrophilicity and reducing mass transfer resistance through membrane pore channels. The deposition of ZnO was systemically performed for 4–128 cycles of ALD at 170 °C. Analysis of membrane surface by contact angles (CA) measurements revealed that the hydrophilicity of the ZnO ALD membrane was enhanced with increasing the number of ALD cycles. It was observed that a vacuum-assisted ‘flow-through’ evaporation method had significantly higher efficacy in comparison to conventional desalination methods. By using the vacuum-assisted ‘flow-through’ technique, the water flux of the ZnO ALD membrane (~170 L m−2 h−1) was obtained, which is higher than uncoated pristine membranes (92 L m−2 h−1). It was also found that ZnO ALD membranes substantially improved water flux while keeping excellent salt rejection rate (>99.9%). Ultrasonic membrane cleaning had considerable effect on reducing the membrane fouling.

Preparation and Characterization of Poly(vinylidene) Fluoride Membranes Reinforced by Modified Nano-SiO2 Particles

2014 ◽  
Vol 789 ◽  
pp. 201-204
Author(s):  
Ai Wen Qin ◽  
Xiang Li ◽  
Bo Mou Ma ◽  
Xin Zhen Zhao ◽  
Chun Yi Liu ◽  
...  
Keyword(s):  
Pore Size ◽  
Vinylidene Fluoride ◽  
Cell Structure ◽  
Membrane Surface ◽  
Pure Water ◽  
Water Flux ◽  
Cross Sectional ◽  
Antifouling Property ◽  
Poly Vinylidene Fluoride ◽  
Mechanical Performances

Poly (vinylidene fluoride) (PVDF) hybrid membranes reinforced by hydrophilic nanoSiO2 particles were fabricated from PVDF/N-dimethylacetamide (DMAc)/γ-butyrolactone (γ-BL) system via thermally induced phase separation (TIPS) process. Surface and cross-sectional morphology of membranes were characterized by scanning electron microscope (SEM). The properties such as permeability, mechanical performances and antifouling property were also determined. The results showed that the pore size of membrane surface became smaller, while cross-sectional morphology was changed from bicontinuous structure to cell structure, the pore size became larger and majorities of closed pores became open with the addition of hydrophilic nanoSiO2 particles in the system. Compared with pure membrane, pure water flux of hybrid membrane increased by 30.3%, i.e. from 290 to 378 L/(m2·h·0.1MPa), antifouling property increased from 63.1% to 80.2%. Meanwhile, tensile strength and elongation at break increased by 70.6% and124%, respectively.

scholarly journals Enhanced flux performance of polyamide composite membranes prepared via interfacial polymerization assisted with ethyl formate

2017 ◽  
Vol 76 (7) ◽  
pp. 1884-1894 ◽  
Author(s):  
Zhaofeng Liu ◽  
Guiru Zhu ◽  
Yulin Wei ◽  
Dapeng Zhang ◽  
Lei Jiang ◽  
...  
Keyword(s):  
Reaction Zone ◽  
Organic Phase ◽  
Interfacial Polymerization ◽  
Water Flux ◽  
Composite Membranes ◽  
Ethyl Formate ◽  
Water Contact ◽  
Tfc Membrane ◽  
High Level ◽  
Trimesoyl Chloride

A novel thin film composite (TFC) polyamide reverse osmosis membrane was prepared via the interfacial polymerization of m-phenylene diamine (MPD) in aqueous phase and 1,3,5-trimesoyl chloride (TMC) in organic phase on a polysulfone ultrafiltration support by assisting with ethyl formate as a co-solvent added in the organic phase. The ethyl formate added in the organic phase is intended to form a narrow miscibility zone, which leads to the thicker reaction zone. The multi-layered loose polyamide structure with larger pore size was formed due to the thicker reaction zone and lower content of MPD. The enhanced hydrophilicity of the membrane was proved by the decreased water contact angle. Water flux was measured at 1.6 MPa with 2,000 ppm NaCl aqueous solution. Compared to the TFC membrane prepared without ethyl formate, the water flux across the TFC membrane with ethyl formate in the organic phase increased with the increased ethyl formate content (from 23 to 45 L/(m2 h)) and the salt rejection remained at a high level (>90%). The ethyl formate can be used as a co-solvent to effectively enhance the performance of the TFC membrane.

scholarly journals TiO2 Polyamide Thin Film Nanocomposite Reverses Osmosis Membrane for Water Desalination

Membranes ◽  
2018 ◽  
Vol 8 (3) ◽  
pp. 66 ◽  
Author(s):  
Ahmed Al Mayyahi
Keyword(s):  
Thin Film ◽  
Interfacial Polymerization ◽  
Water Flux ◽  
Water Desalination ◽  
Fouling Resistance ◽  
Force Microscopy ◽  
Membrane Performance ◽  
Angle Measurements ◽  
Membrane Characterization ◽  
Trimesoyl Chloride

In this study, TiO2 nanoparticles were inserted into the polyamide layer of traditional thin film composite membrane. The nanoparticles were dispersed in a trimesoyl chloride-hexane solution before interfacial polymerization with m-phenylenediamine-aqueous solution. Membrane characterization was performed via contact angle measurements, atomic force microscopy (AFM), scanning electron microscopy (SEM), and water flux, salt rejection, and fouling resistance evaluation. The results indicate that TiO2 could effectively improve membrane performance. Water flux increased from 40 to 65 L/m² h by increasing NPs concentration from 0 to 0.1 wt. %, while NaCl rejection was above 96%. Moreover, the modified membrane demonstrated better organic fouling resistance and robust antibacterial efficiency.

scholarly journals Removal of multiple pesticide residues from water by low-pressure thin-film composite membrane

2020 ◽  
Vol 10 (12) ◽  
Author(s):  
Ayan Mukherjee ◽  
Romil Mehta ◽  
Soumen Saha ◽  
A. Bhattacharya ◽  
Pabitra Kumar Biswas ◽  
...  
Keyword(s):  
Thin Film ◽  
Interfacial Polymerization ◽  
Water Flux ◽  
Size Exclusion ◽  
Film Composite ◽  
Thin Film Composite ◽  
Gas And Liquid Chromatography ◽  
Pass Through ◽  
Polyamide Membrane ◽  
Trimesoyl Chloride

AbstractThe study evaluated removal efficiency of 43 pesticides from water by thin-film composite polyamide membrane indigenously prepared by interfacial polymerization of 1,3-phenylenediamine and 1,3,5 trimesoyl chloride coated on asymmetric polysulfone support. Membrane performance was evaluated by gas and liquid chromatography mass spectroscopy determination of multiple pesticides remaining in feed and permeated water following the application of pesticides each @ 0.02, 0.05, and 0.10 mg/L in de-ionized water. The membrane was most efficient in the rejection of persistent organochlorine insecticides, viz. endosulfans (100%), dichlorodiphenyltrichloroethane (95%), and hexachlorocyclohexane (92%). Out of 43 selected pesticides, 33 were removed by > 80%. Size exclusion mass transfer played a significant role for molecules to pass through the membrane as observed for endosulfan isomers, endosulfan sulphate, and difenoconazole with molecular weight > 400. Pesticide rejection was also related to hydrophobicity (Log P). Hydrophobic pesticides with log P > 4.5 were rejected by > 80%, while monocrotophos with less hydrophobicity (log P = − 0.22) exhibited poor rejection (38%). Water flux decreased with an increase in pesticide concentration. The process of pesticide filtration was optimized at 200 psi. The results indicated the potential of the membrane to remove pesticides from water.

Study on Compositions in Aqueous Phase of Hollow Fiber Composite Nanofiltration Membrane

2012 ◽  
Vol 529 ◽  
pp. 569-573 ◽  
Author(s):  
Lei Wen ◽  
Wei Wang
Keyword(s):  
Phase Composition ◽  
Aqueous Phase ◽  
Hollow Fiber ◽  
Interfacial Polymerization ◽  
Fiber Composite ◽  
Water Flux ◽  
Sulfamic Acid ◽  
Nanofiltration Membrane ◽  
Trimesoyl Chloride ◽  
Polymerization Method

Hollow fiber composite nanofiltration (NF) membranes were prepared by interfacial polymerization method, with polysulfone (PSF) hollow fiber ultrafiltration membrane as base membrane, piperazine (PIP) as the aqueous phase monomer and trimesoyl chloride (TMC) as the organic phase monomer. The effects of aqueous phase composition on composite NF were discussed. The experimental results show that the optimum compositions in aqueous phase: 1wt% PIP, 0.05wt% MPDA, 1wt% TEA, 3wt% sulfamic acid. The best rejection to MgSO4 was 94.7%, and water flux was 66.1L•m-2•h-1.

scholarly journals Incorporation of layered double nanomaterials in thin film nanocomposite nanofiltration membrane for magnesium sulphate removal

2018 ◽  
Vol 34 ◽  
pp. 02003 ◽  
Author(s):  
Muhammad Hanis Tajuddin ◽  
Norhaniza Yusof ◽  
Wan Norharyati Wan Salleh ◽  
Ahmad Fauzi Ismail ◽  
Nur Hanis Hayati Hairom ◽  
...  
Keyword(s):  
Thin Film ◽  
Magnesium Sulphate ◽  
Interfacial Polymerization ◽  
Membrane Surface ◽  
Water Flux ◽  
Morphological Structure ◽  
Separation Performance ◽  
Surface Hydrophilicity ◽  
Double Hydroxides ◽  
Thin Film Nanocomposite

Thin film nanocomposite (TFN) membrane with copper-aluminium layered double hydroxides (LDH) incorporated into polyamide (PA) selective layer has been prepared for magnesium sulphate salt removal. 0, 0.05, 0.1, 0.15, 0.2 wt% of LDH were dispersed in the trimesoyl chloride (TMC) in n-hexane as organic solution and embedded into PA layer during interfacial polymerization with piperazine. The fabricated membranes were further characterized to evaluate its morphological structure and membrane surface hydrophilicity. The TFN membranes performance were evaluated with divalent salt magnesium sulphate (MgSO4) removal and compared with thin film composite (TFC). The morphological structures of TFN membranes were altered and the surface hydrophilicity were enhanced with addition of LDH. Incorporation of LDH has improved the permeate water flux by 82.5% compared to that of TFC membrane with satisfactory rejection of MgSO4. This study has experimentally validated the potential of LDH to improve the divalent salt separation performance for TFN membranes.

scholarly journals Preparation and characterization of a novel positively charged composite hollow fiber nanofiltration membrane based on chitosan lactate

RSC Advances ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 4361-4369 ◽  
Author(s):  
Yuantao He ◽  
Jing Miao ◽  
Shunquan Chen ◽  
Rui Zhang ◽  
Ling Zhang ◽  
...  
Keyword(s):  
Hollow Fiber ◽  
Interfacial Polymerization ◽  
Nanofiltration Membrane ◽  
Trimesoyl Chloride ◽  
Positively Charged ◽  
Chitosan Lactate

A positively charged composite hollow fiber nanofiltration (NF) membrane was prepared via interfacial polymerization by using chitosan lactate and trimesoyl chloride (TMC).

Grafted cellulose acetate reverse osmosis membrane using 2-acrylamido-2-methylpropanesulfonic acid for water desalination

2016 ◽  
Vol 16 (4) ◽  
pp. 1046-1056 ◽  
Author(s):  
Ashraf Morsy ◽  
Shaker Ebrahim ◽  
El-Refaie Kenawy ◽  
Tarek Abdel-Fattah ◽  
Sherif Kandil
Keyword(s):  
Cellulose Acetate ◽  
Reverse Osmosis ◽  
Membrane Surface ◽  
Water Flux ◽  
Contact Angles ◽  
Water Desalination ◽  
Salt Rejection ◽  
Morphological Studies ◽  
Phase Inversion Technique ◽  
Ro Membrane

Reverse osmosis (RO) membranes based on cellulose acetate (CA), were prepared using a phase inversion technique. To improve the hydrophilicity, salt rejection and water flux of these membranes, a novel grafting of 2-acrylamido-2-methylpropanesulfonic acid (AMPSA) was added on the top surface of the CA-RO membranes. The grafted CA-RO membranes were characterized by Fourier transform infrared spectroscopy (FTIR), contact angle, and scanning electron microscopy techniques. It was found that the contact angles were 58° and 45° for pristine CA and 15 wt% grafted CA-RO membranes, respectively, which suggest an increase in the membrane surface hydrophilicity after grafting. The morphological studies of the surface of the pristine CA-RO membrane revealed a typical ridge-and-valley morphology and displayed a relatively high surface roughness of 337 nm, and a significant decrease at 15 wt% of grafted CA-RO membrane to 7 nm. The effect of the grafting percentages of AMPSA on the water flux and salt rejection was studied using a cross flow RO unit. The salt rejection and water flux of the grafted CA-RO membrane with 15 wt% were 99.03% and 6 L/m2h, respectively.

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