An improvement of electrospun membrane reusability via titanium dioxide nanoparticles and silane compounds for the electromembrane extraction

Abstract

A polyacrylonitrile (PAN)/polydimethylsiloxane (PDMS) flat membrane was fabricated by electrospinning technique and modified using titanium dioxide (TiO2) nanoparticles and low-energy materials, dimethyldichlorosilane (MeSiCl2)/methyltrichlorosilane (MeSiCl3), to obtain a hydrophobic surface. The new membrane was utilized for the electromembrane extraction (EME) of model molecules including dibutyl phthalate (DBP) and bis [2-ethylhexyl] phthalate (DEHP). The parameters affecting proposed EME were optimized by the response surface methodology (RSM) based on the central composite design (CCD). The optimized values were 200 V of voltage, 20 min of extraction time, 1100 rpm of agitation rate, 10 mL of donor phase volume and 1 mL of acceptor phase volume. From the results, the performance of EME with the new (modified) membrane remained almost constant after ten extraction cycles while the extraction performance of unmodified EME steeply fell after six extraction cycles. The limits of detection (LODs) for DBP and DEHP were 7.40 and 0.08 ng mL−1, respectively. The linear dynamic range (LDR) was in the range of 100–4000 ng mL−1 for DBP and 1–2000 ng mL−1 for DEHP. The relative standard deviations (RSDs) were below 10%, and the relative recoveries were over 86%. The overall energy consumption for the extraction of the model molecules by new EME was 13.4 kWh m−3. The approach is time-efficient and cost-effective, as the fabricated membrane has better reusability than the previous membranes used for EME.