(174ao) Hybrid Liquid Membrane Method for Removal of Arsenic from Drinking Water

Presence of arsenic in different water bodies above the permissible limit is a major issue all over the world. Researchers are investigating different methods for the removal of arsenic from water that include adsorption, coagulation, ion exchange, oxidation and membrane technologies. This research intends to study the process of removal of arsenic by combining two processes, viz. supported liquid membrane based separation technique and electrocoagulation method. Liquid membrane based separation technique is being studied for its high selectivity and high separation factor. Electrocoagulation further aides in the recovery of arsenic, in turn, improving the removal efficiency of arsenic without addition of any chemical coagulant or adsorbent.

Liquid membrane based separation technique consists of two aqueous phase separated by the immiscible organic phase. The organic phase consists of a mixture of Aliquat and an environmentally benign solvent like sesame oil. One of the aqueous phase is the feed phase acting as the source of arsenic (synthetic water prepared by dissolving arsenic salts) and the other aqueous phase is the receiving phase where electrocoagulation is being conducted using iron plate (anode) and graphite rod (cathode) as electrodes. In this way, arsenic is extracted from feed phase and recovered as iron-arsenic complex in the receiving phase, simultaneously. The parameters affecting the removal efficiency of arsenic such as variation in the concentration of feed and receiving phases, pH of both the aqueous phases and concentration of extractant in the liquid membrane are being studied.