Mohammad Nematzadeh - Department of Chemical Engineering, University of Sistan and Baluchestan, Zahedan, Iran
Abdolreza Samimi - Department of Chemical Engineering, University of Sistan and Baluchestan, Zahedan, Iran
Soheila Shokrollahzadeh - Department of Chemical Technologies, Iranian Research Organization for Science and Technology
Davod Mohebbi-Kalhori - Department of Chemical Engineering, University of Sistan and Baluchestan, Zahedan, Iran

Although bentazon is widely used as an agricultural herbicide, it is harmful to humans and poses many environmental threats. This study focused on the treatment of wastewater contaminated with bentazon pesticides using membrane technology. In this regard, low-pressure reverse osmosis (RO) was employed as it has already been used in the removal of other micro-pollutants. The effects of process variables on water flux and bentazon rejection were studied: temperature, pressure, and bentazon feed concentration. Based on central composite design (CCD), the quadratic model was engaged to correlate the process variables with the water flux and the bentazon removal responses. The obtained results showed that the bentazon rejection increased by enhancing the pressure while it decreased at higher feed solution concentration. However, with increasing temperature, the amount of bentazon removal was reduced. A bentazon rejection efficiency of ۱۰۰ % could be achieved under optimum conditions (i.e., the temperature of ۲۹.۸ ℃ and hydrostatic pressure of ۱۲.۶ bar for a feed solution concentration of ۶۶.۹ mg/L). Therefore, reverse osmosis can effectively remove bentazon.

Membrane technology, Optimization, Wastewater treatment, Reuse, Bentazon