Application of nanofiltration for the removal of carbamazepine, diclofenac and ibuprofen from drinking water sources

Investigation of ciprofloxacin removal from aqueous solution by nanofiltration process

“…In addition, solutes can be rejected on NF membrane by one or a combination of three basic mechanisms including size exclusion (sieve steric effect), charge exclusion (electrical, Donnan), and physico-chemical interactions between solute, solvent and membrane (Yoon et al, 2006;Acero et al, 2010;Dolar et al, 2011;Sun et al, 2011;Vergili, 2013). Moreover it is also reported in the literature that size exclusion in tight membranes and charge exclusion and physicochemical interaction in the other membranes were more effective mechanisms in membrane filtration (Dolar et al, 2011).…”

“…Figure 8 showed that, the rejections at original pH values on three membranes were very much higher than the rejections at the other pH values. Urase et al, (2007) and Vergili (2013) determined that under suitable operating conditions, almost same rate of drugs was removed on the tight membranes and generally a removal efficiency of above 95 percent was obtained. In this study, TOC rejection was found to be above 90 percent for each three membrane at original pH value.…”

“…Solubility changing with the pH of the solution, charge, dissociation constant (pKa), polarity, dipole moment and hydrophobicity expressed as the octanol-water partition coefficient compounds (log Kow) are important physico-chemical properties that affect the rejection of the compounds and the membrane flux (Yoon et al, 2006;Nghiem et al, 2005;Vergili, 2013).…”

“…pKa value of the solute is an important parameter in the rejection of organic micropollutants, and it determines the charge of the solute in relation to the feed pH (Vergili, 2013). As defined in the literature, despite the low log Kow value (0.28) and hydrophilic property of CIPRO, the general characteristics of which were given in Table 2, its adsorption to membrane surface occurs very little, and the main rejection mechanism (beside the size exclusion) depends on membrane materials and solution pH which makes the study of CIPRO rejections at different pH values important.…”

“…The contact angle, which was 27.7° in the clean membrane, increased up to 61.0° for NF270 membrane at the same operating conditions while it increased from 41.4° up to 62.9° for DS-5DK membrane. As it is known that there is a direct proportion between hydrophobicity and contact angle (Vergili et al, 2013), it can be concluded that the hydrophobic property is dominant and these latter two membranes are more sensitive to pollution.…”