BORON REMOVAL FROM INDUSTRIAL WASTE WATER USING HYBRID ADSORPTION-MEMBRANE SYSTEM

Abstract

The production of industrial wastewater containing heavy metals pollutants, including boron has caused a great deal of concern due to high concentration which is toxic and harmful to the environment. Several treatment technologies including, adsorption, electrocoagulation, chemical coagulation, chemical precipitation and membrane have been reported in eliminating boron from a generated effluent before discharge. The current study utilizes a hybrid system comprising of three compartments, namely adsorption, settling, and membrane compartment. Initially, at the adsorption section of the hybrid system, the wastewater was subjected to adsorption process for 250 minutes, using nano-magnetite sorbent. The remedied effluent was examined, and a considerable performance was noticed in the removal efficiencies of boron, turbidity, copper, and zinc with 74.39 %, at 250 minutes contact time. Though, the sorbent was able to achieve 74.39% boron removal rate alongside with 2.2 mg/L concentration. However, this concentration is still above the WHO/EU/DOE (0.5-1.0 mg/L) standard limit. Application of further treatment process became imperative to meet the standard discharge limit. A nanocomposite membrane was employed as treatment process to improve the efficiency of boron removal. The contaminants removal rate for neat (PVDF-PVP) and modified (1.0 wt% TiO₂) membranes in respect to boron. The physicochemical analysis of the permeate revealed that the boron concentration was significantly reduced to 0.43 mg/L, which is far lower than the discharge limit of 1.0 mg/L. Finally, the modified hybrid TiO₂ membrane has demonstrated to be effective in relegating boron from the wastewater.