Time filter

Source Type

Shen J.-N.,Zhejiang University of Technology | Ruan H.-M.,Zhejiang University of Technology | Wu L.-G.,Zhejiang GongShang University | Gao C.-J.,National Engineering Research Center for Liquid Separation Membrane
Chemical Engineering Journal

Ultrafiltration (UF) has become an accepted process for drinking water treatment, but membrane fouling remains a significant problem. Polyethersulfone (PES)/SiO2 composite membranes were prepared by phase inversion method with nano-SiO2 as additive. Water contact angle measurement was conducted to investigate the hydrophilicity and surface wettability of the membranes. The effect of SiO2 nanoparticles on the membrane permeation properties, anti-fouling performances, and membrane morphologies and structures was examined and discussed. The influence of SiO2 on the water permeability, anti-fouling of the PES membranes were evaluated by raw water UF experiments. The results showed that the membrane structure was not obviously affected by addition of SiO2, and the membrane performances such as hydrophilicity and anti-fouling ability were enhanced by adding SiO2 nanoparticles. © 2011 Elsevier B.V. Source

Wang Y.-X.,Zhejiang GongShang University | Shen J.-N.,Zhejiang University of Technology | Wang T.,Zhejiang GongShang University | Du C.-H.,Zhejiang GongShang University | And 2 more authors.
Gongneng Cailiao/Journal of Functional Materials

Multi-walled carbon nanotubes (MWCNT) were modified by HNO3/H2SO4 mixture and diaminodiphenyl methane (MWCNT-NH2), and then MWCNT-NH2/poly(MMA-AM) hybrid membranes were prepared through in-situ copolymerization of MWCNT-NH2, methyl methacrylate (MMA) and acrylamide (AM). The structure of MWCNT, and MWCNT-NH2 were characterized by Raman spectrum, FT-IR, scanning electron microscopy (SEM). The structure and performance of the hybrid membranes were analyzed by SEM, zeta potential and sorption-swelling behavior. The results shown that the modification of MWCNT promoted the dispersion of MWCNT-NH2 in MWCNT-NH2/poly(MMA-AM) hybrid membranes. The equilibrium swelling degree of benzene (A∞, b) was higher than that of cyclohexane (A∞,c) in the hybrid membranes, but the sorption-swelling selectivity of benzene to cyclohexane (αS,b/c) of MWCNT-NH2/poly(MMA-AM) was higher than that of MWCNT/poly(MMA-AM). A∞,b and αS,b/c increased with increase of MWCNT-NH2 content (c) in MWCNT-NH2/poly(MMA-AM) hybrid membranes, and the equilibrium swelling degree of cyclohexane (A∞,c) was less changed. MWCNT-NH2/poly(MMA-AM) hybrid membrane displays a characteristics of benzene preferentially selective sorption-swelling for separation of benzene/cyclohexane mixture. Source

Shen J.N.,Zhejiang University of Technology | Yu C.C.,Zhejiang University of Technology | Ruan H.M.,Zhejiang University of Technology | Gao C.J.,National Engineering Research Center for Liquid Separation Membrane | Van der Bruggen B.,Catholic University of Leuven
Journal of Membrane Science

Carbon nanotube enhanced thin-film nanocomposite membranes were prepared by incorporating carbon nanotubes (CNTs) into the active layers of membranes used for water treatment. For inclusion into these active layers, a grafting procedure for carbon nanotubes was set up to increase their hydrophobicity. Multiwalled carbon nanotubes (MWNTs) grafted by poly(methyl methacrylate) (PMMA) were synthesized via a microemulsion polymerization of methyl methacrylate (MMA) in the presence of acid-modified multiwalled carbon nanotubes (c-MWNTs). Subsequently, polyamide thin-film nanocomposite (TFN) membranes containing PMMA-MWNTs were prepared via interfacial polymerization. Morphology studies demonstrate that MWNTs have been successfully embedded into the active polyamide layer. The rejection of Na2SO4 was high (99%), and the water flux was about 62% increased compared to the thin-film composite membrane when using 2g/L piperazine (PIP) in the aqueous phase, 4g/L trimesoyl chloride (TMC) and 0.67g/L PMMA-MWNTs in the organic phase, which demonstrates that PMMA-MWNTs significantly improve selectivity and permeability. © 2013 Elsevier B.V. Source

Zou K.,Zhejiang University | Wang L.,Tangshan Teachers College | Zhang L.,Zhejiang University | Chen H.,Zhejiang University | And 2 more authors.
Huagong Xuebao/CIESC Journal

A nanofiltration (NF) composite membrane, with an ultra-thin skin layer, was prepared through interfacial polymerization on a polysulfone support with trimesoyl chloride (TMC) and a key aqueous monomer trimesoyl piperazine (TMPIP) hydrochloride with branched triimine structure, which was designed and synthesized based on the principle of interfacial polymerization of TMC and piperazine (PIP). Fourier transform infrared spectroscopy (FTIR) was combined with scanning electron microscope (SEM) to characterize the chemical composition and structure of the skin layer. The results showed that an ultra-thin poly(piperazineamide) skin layer, around 100 nm thick, was formed on the surface of support membrane. Compared with the performance of TMC/PIP composite membrane against PEG 200, the improved performance of TMC/TMPIP composite membrane was attributed to its high crosslinking and ultra-thin skin layer. The performance for aqueous solution of different salts was investigated, and it was found that the rejection and flux were both better than those of TMC/PIP composite membrane, with the same rejection order. © All Rights Reserved. Source

Shen J.-N.,Zhejiang University of Technology | Yu J.,Zhejiang University of Technology | Chu Y.-X.,Zhejiang University of Technology | Zhou Y.,National Engineering Research Center for Liquid Separation Membrane | Chen W.-J.,Zhejiang University of Technology
Advanced Materials Research

Polyacrylonitrile/montmorillonite (PAN/MMT) nanocomposite with amidoxime functionality was prepared from acrylonitrile monomer(AN) and montmorillonite(MMT) through in-situ intercalation polymerization. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction patter (XRD) were employed to characterize the obtained Na-MMT, Organ-MMT, PAN/MMT, APAN/MMT. Effects of preparing conditions of APAN/MMT on adsorption of uranium were investigated. The FT-IR spectra show that the new absorption band at 1653 cm -1( C NH2) appears and the absorption band at 2243 cm -1(-CN) disappears on the spectrum of APAN/MMT, it indicates that the AN and MMT are successfully polymerized by in-situ polymerization and the PAN/MMT is amidoxime functionalized. The APAN/MMT nanocomposite completely lose the X-ray diffraction. The adsorption results show that the obtained APAN-MMT gives uranium adsorption capacity of 3.06 mg.g- 1 under following conditions: uranium ion concentration of 10 mg/L, AM mass concentration of 80.0%, initiator of 4.5%, polymerization temperature of 70 °C, polymerization time of 3 h, pH of 7 and amidoxime functionalized reaction time of 2 h. © (2012) Trans Tech Publications. Source

Discover hidden collaborations