Arsenate Removal from Wastewater Using Solid Phase Extraction (SPE) Onto Functionalized Polyvinylbenzylchloride-Based Diquaternary Ammonium Nanofibres

Abstract

An estimated 30 to 35 million Bangladesh people are exposed to arsenic concentrations above 50 µgl^−1 (World Health Organization (WHO) guideline value prior to 1993), and the number of people exposed to more than 10 µgl^−1 (current WHO guide line value) is 46 to 57 million. The problem of wastewater is acute among developing and industrialized countries that are still struggling with the toxic effect of waste water. Efforts are being made to remove these contaminants, arsenic (v) from wastewater using low cost adsorbents. The removal of arsenic(v) from wastewater using two novel fabricated sorbent materials; aminated polyvinylbenzylchloride (PVBC) prepared through a substitution reaction and then quaternized using three alkyl groups (R' = CH₃, C₂H₅ and C₃H₇) were investigated. The experiments were carried out in solid phase extraction mode. Preliminary experiments were done with series of three sorbent materials (R' = CH₃, C₂H₅ and C₃H₇) in order to find out a suitable and low-cost adsorbent for the effective removal of arsenic (v). The best sorbent materials were obtained after the optimization and preparation experiments. The R' = CH₃ were effective for arsenic (v) removal from wastewater. The effect of pH, initial sorbate concentration, amount of sorbent, effect of co-existing anions and the reusability in solid phase extraction mode were also investigated. From the experiment conducted, the pH shows a decisive factor on arsenic removal. Analysis of adsorbent dosage, Kinetic studies and co-existing anions were carried out in order to evaluate sorption parameters.