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Walkerton, Canada

Narbaitz R.M.,University of Ottawa | Rana D.,University of Ottawa | Dang H.T.,University of Ottawa | Morrissette J.,University of Ottawa | And 4 more authors.
Chemical Engineering Journal | Year: 2013

To maximize the removal of charged pharmaceutical and personal care products (PPCPs), modified cellulose acetate (CA) nanofiltration (NF) membranes were developed by incorporating charged surface modifying macromolecules (CSMM) to increase their surface charge. The objective of this study was to evaluate their removal of trace levels of PPCPs at two water treatment plants. This new membrane and a commercial thin-film composite (TFC) NF membrane (Filmtec NF-270) were tested simultaneously in the field using two SEPA cells. The testing was conducted at the Britannia Water Treatment Plant (Ottawa, ON) and the Walkerton Clean Water Centre (Walkerton, ON). The challenge waters were filter effluents spiked with ppt and ppb levels of carbamazepine (CBZP), ibuprofen (IBUP) and sulfamethazine (SFMZ). The new experimental modified CA membrane achieved very good IBUP removals, good SFMZ removals and poor CBZP removals. The commercial TFC NF membrane (NF-270) had better removals and significantly higher fluxes than the modified CA membrane. The larger removals are not surprising given that the commercial membrane is the result of extensive development and optimization, while the modified CA membrane has undergone very limited optimization. The larger flux of the NF-270 membrane is also expected given that this is a TFC membrane, while the experimental modified membrane was prepared via a single casting step via the phase inversion technique which produces a thicker skin layer. © 2013 Elsevier B.V.

Rana D.,University of Ottawa | Scheier B.,University of Ottawa | Scheier B.,University of Waterloo | Narbaitz R.M.,University of Ottawa | And 4 more authors.
Journal of Membrane Science | Year: 2012

Pharmaceutical and personal care products (PPCPs) enter the environment mainly through municipal wastewater effluents, agricultural run-off, pharmaceutical and related chemical industry discharges. The present study was conducted to remove PPCPs through nano-filtration (NF) membranes prepared with two different tailor-made polymeric additives. The first is a novel charged surface modifying macromolecule (CSMM) additive synthesized by reactive diisocyanate and dihydroxy naphthalene disulfonate. The second additive was a tailor made hydrophi. lic SMM (LSMM), which was manufactured incorporating poly(ethylene glycol) as end groups. Cellulose acetate (CA) membranes with and without 3. wt% CSMM or LSMM were prepared by the phase inversion technique. The membranes were characterized by static contact angle, X-ray photoelectron spectroscopy, scanning electron microscopy with energy dispersive spectrometer, and atomic force microscopy. The NF filtration studies were conducted at two different operating pressures (150 and 400. psig). They consisted of pure water flux tests, sodium chloride separation tests, and individual PPCP (ppm level carbamazepine, ibuprofen, and sulfamethazine) separation tests. The long term NF performance for the removal of ibuprofen was also conducted. Significant effect of CSMM blending on the separation performance of ibuprofen for long hours operation was observed. © 2012 Elsevier B.V.

Rana D.,University of Ottawa | Narbaitz R.M.,University of Ottawa | Garand-Sheridan A.-M.,University of Ottawa | Westgate A.,University of Ottawa | And 3 more authors.
Journal of Materials Chemistry A | Year: 2014

The aim of this study was to develop novel surface-modified poly(ether sulfone) (PES) ultra-filtration (UF) membranes for removal of endocrine disrupting chemicals (EDCs) and pharmaceutical and personal care products (PPCPs). Seven tailor-made charged surface modifying macromolecules (CSMMs) were developed for use as additives in the preparation of PES UF membranes with a greater surface charge and improved PPCP and EDC removal through charge repulsion. Twenty three types of PES membranes were prepared using two amounts of different CSMMs and two drying (or evaporation) times. The experiments were designed to obtain the membranes' performances in terms of normalized standard flux (NSF), molecular weight cut-off (MWCO), surface charge (SC), static contact angle and their removal efficiency towards one EDC (bisphenol A) and three PPCPs (carbamazepine, ibuprofen, and sulfamethazine). The correlation between NSF versus SC, MWCO, pore density, and porosity was discussed. The filtration experiments showed an initial partial removal of the target compounds, but no removal in the later stages of operation, which indicated that charge repulsion was not the controlling removal mechanism. This is consistent with small changes in membrane surface charge achieved by addition of these additives. Given the decrease in the percent removal with time, removal by size exclusion was also not significant as expected because the membranes had a MWCO greater than 10 kilo-Dalton while the target compounds had molecular weights in the 200 to 300 Dalton range. Based on the decreasing level of removal with time, it appeared that adsorption was the main removal mechanism. 2014 This journal is © the Partner Organisations.

Borikar D.,Walkerton Clean Water Center | Borikar D.,University of British Columbia | Mohseni M.,University of British Columbia | Jasim S.,ON
Water Quality Research Journal of Canada | Year: 2015

Although potential risk of pharmaceuticals and personal care products (PPCPs) and endocrine disrupting compounds (EDCs) and trihalomethanes to humans is small or unconfirmed, it is advisable to remove these wastewater-related contaminants to increase public confidence and acceptance as a precautionary principle and consequently their elimination or reduction during drinking water treatment is warranted. Experiments were conducted using the dual train pilot-scale conventional treatment plant with ozone and ultraviolet/hydrogen peroxide (UV/H2O2) with three different raw water sources. Reductions of trihalomethanes-formation potentials (THM-FPs) were 8–52%. Ozone was found to decrease THM-FPs while UV/H2O2 was found to increase THM-FPs in most of the experiments under experimental conditions. Conventional treatment poorly removed the selected PPCPs and EDCs while ozone þ conventional treatment provided excellent removal. ConventionalþUV/H2O2 treatment also demonstrated effective removal. However, removal of PPCPs and EDCs by conventionalþUV/H2O2 treatment provided lower efficacy for Sites B and C, likely due to the presence of scavengers such as organics, bicarbonates, carbonates and particles. © IWA Publishing 2015.

Borikar D.,Walkerton Clean Water Center | Borikar D.,University of British Columbia | Mohseni M.,University of British Columbia | Jasim S.,SJ Environmental Consultants Inc.
Ozone: Science and Engineering | Year: 2015

Pharmaceuticals and personal care products (PPCPs), endocrine disrupting compounds (EDCs) and disinfection by-products are suspected to have potential adverse impact on humans and hence their elimination during drinking water treatment is often desired or regulated. Based on pilot-plant experiments with three raw water sources, conventional treatment poorly removed the selected PPCPs and EDCs, while ozone/H2O2 and UV/H2O2 (both) with conventional treatment effectively removed PPCPs and EDCs. In most of the experiments, ozone/H2O2 + conventional treatment additionally removed THM formation potentials (THM-FPs) compared to those of conventional treatment. However, UV/H2O2 treatment was found to increase THM-FPs compared to conventionally treated water. © 2015, Copyright © 2015 International Ozone Association.

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