Use of polymeric membranes for the treatment of oily wastewater: Modification using inorganic nanoparticles and optimization of filtration parameters

Polymeric membranes have proven to be an effective method for the treatment of contaminated waters. Many factors influence their performances including the operating parameters, fabrication process and conditions, and modifications using different additives. Introduced as additives, nanoparticles are capable of enhancing membrane performance via their intrinsic properties which include morphology, core size, and chemical nature. Nevertheless, common problems, such as nanoparticle agglomeration or leaching and the formation of defective areas, may occur during the membrane fabrication. These issues depend on several factors which were observed to influence the membrane morphology and structure and consequently influence the effectiveness of water treatment. Accordingly, different strategies were investigated to avoid effectiveness issues. In this work, we first reviewed the effects of three nanoparticles, namely, Titanium, Silica, and Aluminum on the performance of polymeric membranes devoted to the treatment of organic waste streams. Major effects related to fabrication conditions were investigated different strategies used to improve polymer performance were highlighted. Secondly, we studied the performance of PVDF membrane modified with silica, iron, and silica hybridized iron nanoparticles. As anticipated, amorphous silica showed great performance in the improvement of membrane hydrophilicity. However, this enhancement is associated, in most cases, with the drop in the rejection capacity due to the trade-off relation between permeability and selectivity. On the other hand, iron nanoparticles exhibited great results in the enhancement of the polymer rejection rate. In the experimental work, we proceeded to the hybridization of iron nanoparticles using silica nanomaterials through the modified Stöber process. The obtained membranes were characterized using AFM and SEM and the synthesized nanoparticles were analyzed via XRD and TEM microscope. The fabricated membranes were tested for the treatment of oily wastewater under stable operating parameters of transmembrane pressure (TMP) of 2 bars, cross-flow velocity (CFV) of 0.5 m/s, room temperature, and a feed pH of 7 to evaluate their performance in hydrophilicity, oil rejection rate, and Flux Recovery Ratio (FRR). PVDF/Fe@SiO2 membrane exhibited the highest pure water flux of 932.63 (L·m−2·h−1) with an oil rejection rate of 78.71% compared to 355.51 (L·m−2·h−1) and 52% for the bare PVDF. These enhancements demonstrate that the membrane modified with iron hybridized silica NPs was able to avoid the trade-off relation due to the combined effects of silica and iron on the improvement of the membrane’s performance. Finally, we proceeded to the optimization of the filtration operational parameters using the Taguchi method and we investigated the prediction of membrane flux using Artificial Neutral Network (ANN) modelling. Although the Taguchi method showed optimum filtration parameters at TMP of 2 bars, CFV of 0.75 m/s, acid pH of 5 and feed temperature of 35 °C, the ANN modelling was able to predict the permeate flux of the membrane at different operating conditions and confirmed an excellent fit with the experimental data.

Name thesis:degree_name

Master of Applied Science (MASc)

Level thesis:degree_level

Master's

Discipline thesis:degree_discipline

Engineering - Process Systems

Grantor dc:publisher

Faculty of Graduate Studies and Research, University of Regina

Year dc:date.issued

2022

Author dc:creator

• Elgharbi, Hassan

Advisor dc:contributor.advisor

• Henni, Amr

Committee member dc:contributor.committeemember

• Ibrahim, Hussameldin

Language dc:language.iso

en

DOI

https://doi.org/10.82465/4603

OAI identifier oai:identifier

oai:uregina.scholaris.ca:10294/16049