Effects of organic and inorganic matter on pesticide rejection by nanofiltration

Membrane Treatment of Potable Water for Pesticides Removal

“…However, the calcium retention was reduced somewhat, by approximately 7% and 13% for the tight NF90 and XLE membranes, respectively. Furthermore, the presence of calcium ions had no influence on herbicide adsorption on all membranes tested, as also observed by previous researchers (Boussahel et al, 2002).…”

“…In an earlier study (Boussahel et al, 2002), the presence of divalent cations (calcium) in the feed solution appeared to exercise little influence on pesticide rejection, whereas rejection was found to be related to the membrane type. Specifically, an improvement in pesticide rejection by approx.…”

“…5% (in the presence of CaCl 2 ) and 10% (in the presence of CaSO 4 ) was reported for a NF200 membrane, while for the Desal DK membrane very little change was noted, i.e. a slight drop in the percent removal (5%) for DEA and simazine with CaCl 2 (Boussahel et al, 2002). These results are in agreement with those from a recent study (Plakas & Karabelas, 2008), where a moderate influence of calcium ions on herbicide retention was obtained; this influence, was either positive or negative depending on the membrane type.…”

“…It has been reported ) that a positive correlation exists between the rejection of eleven pesticides with their molecular weights, from which a MWCO of 200Da was determined for the membrane tested (Dow Filmtec NF70). In pilot studies (Boussahel et al, 2002), the higher rejection of atrazine and cyanazine was attributed to their molecular weight, which is larger than the one characterizing the other three herbicides tested (DEA, simazine and isoproturon). Significant efforts were also made (Van der Bruggen et al, 1999) to correlate the rejection of miscellaneous organic molecules with their molecular weight values as well as with other size parameters with physical meaning (d s , d m , molecular diameter calculated with the HyperChem software).…”

“…Because of this advances in membrane technology, RO has been gradually finding applications in the treatment of a variety of domestic, industrial, and hospital wastewaters. In the past three decades, the need for a complete assessment of the RO, and of the later developed NF process, regarding removal of pesticide residues from various aquatic matrices, led to an extensive research effort in many laboratories (Berg et al, 1997;Devitt et al, 1998a;Van der Bruggen et al, 1998Kiso et al, 2000Kiso et al, , 2002Košutić et al, 2002Košutić et al, , 2005Zhang et al, 2004;Causserand et al, 2005;Bhattacharya et al, 2006;Plakas et al, 2006;Sarkar et al, 2007;Plakas & Karabelas, 2008Ahmad et al, 2008aAhmad et al, , 2008bComerton et al, 2008;Caus et al, 2009;Benítez et al, 2009;Pang et al, 2010;Wang et al, 2010), pilot (Baier et al, 1987;Duranceau et al, 1992;Agbekodo et al, 1996;Berg et al, 1997;Hofman et al, 1997;Wittmann et al, 1998;Bonné et al, 2000;Boussahel et al, 2000Boussahel et al, , 2002Chen et al, 2004) as well as to industrial scale experiments (Agbekodo et al, 1996;Wittmann et al, 1998;Ventresque et al, 2000;Cyna et al, 2002). A fairly large number of commercially available NF/RO membranes have been tested for the removal of an even larger number of herbicides, insecticides, fungicides and miscellaneous pesticides from various water matrices.…”