Effect of Salinity, Electric and Magnetic Field on Phenol Removal using Activated Carbon Derived from Phoenix dactylifera Bio-waste

Abstract

Industrial processes produce toxic organic molecules that pollute the environment and water. Phenol and its derivatives are among the main pollutants in water due to their low biodegradability and highly toxic nature. Therefore, industrial wastewater streams need to be treated to reduce the concentration of phenol before discharge. UAE legislation limits total phenols in industrial wastewater discharged to the marine environment to 0.1 ppm. The objective of this study is to understand the potential of using Phoenix dactylifera bio-waste (date palm wastes) as a resource for the production of activated carbon to remove phenol from oil and gas-produced water. The biomass waste was pyrolyzed and chemically activated with ZnCl2. The specific surface area, BJH pore volume, and radius obtained for the activated carbon were 902 m2 g−1, 0.1296 cm3 g−1, and 17.77 Å, respectively. A detailed characterization of the physicochemical and morphological properties of the activated carbons derived from biomass waste was carried out. The full factorial experimental design was also carried out to investigate the effect of three variables: initial concentration of phenol, pH, and salinity, and to optimize the condition to achieve high adsorption uptake capacity. An adsorption study with two modes of operation (batch and continuous) was conducted using the optimized condition to investigate the potential of using the activated carbons for phenol removal from produced water. The effects of solution salinity, electric potential, and magnetic field on phenol removal efficiency were investigated. The results showed that the pseudo-second-order kinetic model better describes the kinetics of adsorption. Langmuir's isothermal model was the best at describing phenol adsorption on activated carbons from biomass waste compared to the Freundlich, Sips, and Dubinin−Radushkevich models. The maximum adsorption uptake capacity of 47.23 mg/g was obtained by applying a magnetic field using the aluminum substrate. It is around a 5.45% increase compared to the adsorption uptake capacity without applying a magnetic field.

Date of Award	Jul 2021
Original language	American English