Impact of polymeric membrane filtration of oil sands process water on organic compounds quantification

Abstract

The interaction between organic fractions in oil sands process-affected water (OSPW) and three polymeric membranes with varying hydrophilicity (nylon, polyvinylidene fluoride and polytetrafluoroethylene) at different pHs was studied to evaluate the impact of filtration on the quantification of acid-extractable fraction (AEF) and naphthenic acids (NAs). Four functional groups predominated in OSPW (amine, phosphoryl, carboxyl and hydroxyl) as indicated by the linear programming method. The nylon membranes were the most hydrophilic and exhibited the lowest AEF removal at pH of 8.7. However, the adsorption of AEF on the membranes increased as the pH of OSPW decreased due to hydrophobic interactions between the membrane surfaces and the protonated molecules. The use of ultra pressure liquid chromatography-high resolution mass spectrometry (UPLC/HRMS) showed insignificant adsorption of NAs on the tested membranes at pH 8.7. However, 26±2.4% adsorption of NAs was observed at pH 5.3 following the protonation of NAs species. For the nylon membrane, excessive carboxylic acids in the commercial NAs caused the formation of negatively charged assisted hydrogen bonds, resulting in increased adsorption at pH 8.2 (25%) as compared to OSPW (0%). The use of membranes for filtration of soluble compounds from complex oily wastewaters before quantification analysis of AEF and NAs should be examined prior to application.

Assessing spatial and temporal variability of acid-extractable organics in oil sands process-affected waters

“…SFS analysis was not capable of identifying differences within either sample set, but a slight difference between the two industries was observed ( Figure S1). The additional maxima detected by SFS in the Industry B samples (359 and 373 nm) have not been reported previously (Kavanagh et al, 2009;Frank et al, 2014;Moustafa et al, 2014), suggesting that the aromatic acids associated with these maxima could be among the 849 entities unique to Industry B ( Figure S4) and potentially useful for source identification.…”

Formation and electrical characterization of black lipid membranes in porous filter materials

“…The contact angle of water with the PVDF filter could not be accurately determined because of the high water permeability of this filter and hence no droplet could be formed . Despite this inherent difficulty, Moustafa et al reported a contact angle of a PVDF filter of 69.8°.…”

Mine Drainage and Oil Sand Water

“…The impact of filtration on the quantification of AEF and NAs was studied using three polymeric membranes with varying hydrophilicity (Moustafa et al, 2014). Four functional groups predominated in OSPW (amine, phosphoryl, carboxyl and hydroxyl) and the nylon membranes were the most hydrophilic, exhibiting the lowest AEF removal at a pH of 8.7.…”