The transport of selected salts of sulphuric acid (cobalt, copper, iron(II), manganese, nickel
and zinc sulphate) through an anion-exchange membrane Neosepta-AFN was investigated in a countercurrent
continuous dialyzer at various salt concentrations and volumetric liquid flow rates. The basic
transport characteristics − the rejection coefficient of salt and the permeability of the membrane − were
calculated from measurements at steady state. The salt concentration in model mixtures was changed in
the limits from 0.1 to 1.0 kmol m−3 and the volumetric liquid flow rate of the inlet streams was in the
limits from 8
diffusion dialysis; anion-exchange membrane; continuous dialyzer; salt of sulphuric acid;
permeability of membrane.
Institute of Environmental and Chemical Engineering, Faculty of Chemical Technology,
University of Pardubice, Studentska 573, 532 10 Pardubice, Czech Republic
A linear quantitative structure-property relationship (QSPR) model is presented for the prediction
of rejection in permeation through membrane. The model was produced by using the multiple linear
regression (MLR) technique on the database consisting of retention data of 25 pesticides in 4 different
membrane separation experiments. Among the 3224 different physicochemical, topological and structural
descriptors that were considered as inputs to the model only 50 were selected using several criteria of
elimination. The physical meaning of chosen descriptor is discussed in detail. The accuracy of the proposed
MLR models is illustrated using the following evaluation techniques: leave-one-out cross validation
procedure, leave-many-out cross validation procedure and Y-randomization.
nanofiltration; retention; pesticides; QSPR analysis.
Department of Organic Chemistry, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz,
Nicolaus Copernicus University, 9 Sklodowskiej-Curie St., 85-094 Bydgoszcz, Poland
Faculty of Chemistry, Nicolaus Copernicus University, 7 Gagarin St., 87-100 Torun, Poland
Organic fouling and biofouling pose a significant challenge to the membrane filtration process.
Photocatalysis-membrane hybrid system is a novel idea for reducing these membranes fouling however,
when TiO2 photocatalyst nanoparticles are used in suspension, catalyst recovery is not only imposes an
extra step on the process but also significantly contributes to increased membrane resistance and reduced
permeate flux. In this study, TiO2 photocatalyst has been immobilized by coating on the microfiltration
(MF) membrane surface to minimize organic and microbial fouling. Nano-sized TiO2 was first synthesized
by a sol-gel method. The synthesized TiO2 was coated on a Poly Vinyl Difluoride (PVDF) membrane
(MF) surface using spray coating and dip coating techniques to obtain hybrid functional composite
membrane. The characteristics of the synthesized photocatalyst and a functional composite membrane
were studied using numerous instruments in terms of physical, chemical and electrical properties. In
comparison to the clean PVDF membrane, the TiO2 coated MF membrane was found more effective in
removing methylene blue (20%) and E-coli (99%).
TiO2 photocatalyst; photocatalysis; microfiltration (MF); organic fouling; biofouling.
School of Civil and Environmental Engineering, University of Technology,
Sydney (UTS), P.O. Box 123, Broadway, NSW 2007, Australia
Photo & Environmental Technology Co. Ltd., Gwangju 500-460, Korea
Center for Seawater Desalination Plants, Gwanju Institute of Science and Technology,
Gwanju, South Korea
Approximately 80% of water used in urban areas reappears as municipal wastewater (MWW).
Reclamation of MWW is an attractive proposition under the present scenario of water stressed cities in
India. In this paper, we attempted to reclaim MWW using lab-scale hollow- fiber (HF) membrane modules
for possible reuse in non-potable applications. Experiments were conducted to evaluate the efficiency of
virgin HF (M1) and modified HF (M2) modules. The M2 module consists of HF modified with a skin
layer formed through interfacial polymerization of m-phenylenediamine with trimesoyl chloride (MPDTMC).
The molecular weight cut-off (MWCO) of M1 was 44000 g/mol and that of M2 10000 -14000 g/mol
on the basis of rejection of polyethylene glycol. The combination of M1 and M2 modules was able to
reduce concentrations of most of the pollutants in sewage and improved the treated water quality to the
acceptable limits for non potable reuse applications. It is found that about 98-99% of the initial flux is
recovered by the backwashing process, which was approximately two times in a month when operated
sewage reclamation; hollow fiber; ultrafiltration; non potable water; reuse.
Wastewater Technology Division, National Environmental Engineering Research Institute (CSIR),
Nehru Marg, Nagpur-440020, India
Reverse Osmosis Discipline, Central Salt & Marine Chemicals Research Institute (CSIR),
Gijubhai Badheka Marg, Bhavnagar-364002, India
Poly(vinylidene fluoride-co-hexafluoropropylene), PVDF-HFP, hollow fiber membranes were
prepared by the dry/wet spinning technique using different polyethylene glycol (PEG) concentrations as
non-solvent additive in the dope solution. Two different PEG concentrations (3 and 5 wt.%). The
morphology and structural characteristics of the hollow fiber membranes were studied by means of optical
microscopy, scanning electron microscopy, atomic force microscopy (AFM) and void volume fraction. The
experimental permeate flux and the salt (NaCl) rejection factor were determined using direct contact
membrane distillation (DCMD) process. An increase of the PEG content in the spinning solution resulted
in a faster coagulation of the PVDF-HFP copolymer and a transition of the cross-section internal layer
structure from a sponge-type structure to a finger-type structure. Pore size, nodule size and roughness
parameters of both the internal and external hollow fiber surfaces were determined by AFM. It was
observed that both the pore size and roughness of the internal surface of the hollow fibers enhanced with
increasing the PEG concentration, whereas no change was observed at the outer surface. The void volume
fraction increased with the increase of the PEG content in the spinning solution resulting in a higher
DCMD flux and a smaller salt rejection factor.
water treatment; poly(vinylidene fluoride-co-hexafluoropropylene); hollow fiber; membrane
Department of Applied Physics I, Faculty of Physics, University Complutense of Madrid,
Av. Complutense s/n, 28040, Madrid, Spain
Department of Chemical Engineering, Faculty of Engineering, An-Najah National University,
P.O. Box 7, Nablus, Palestine