Nadia El Ouahedy
University of Poitiers, France
Title: Preparation of activated carbon from olive waste. Application as adsorbent for persistent organic pollutants in water
Biography
Biography: Nadia El Ouahedy
Abstract
In the present study, we have investigated the adsorption, by activated carbon prepared from olive stones, of two pollutants, Bisphenol A, a substance causes a disruption of endocrine systems and ubiquity in the aquatic environment, and Diuron, a pesticide detected in groundwater and may reach higher levels than health-based standards. The olive stones were chemically activated and then pyrolysed (thermal treatment under nitrogen). On the other hand, to optimize the preparation method, the effect of the main process parameters (such as activating agent used, impregnation ratio, temperature of pyrolysis step) on the performances of the obtained activated carbons (expressed in terms of adsorption capacity of BPA and Diuron and specific surface area) was studied. The physicochemical properties of the activated carbon prepared were characterized by N2 adsorption/desorption, FTIR, SEM, X-Ray diffraction, CHNS and TGA/DTA. To optimize the adsorption parameters of the activated carbon, preliminary experiments were achieved, such as the effects of solution initial pH and temperature, effect of initial concentration of the pollutants. Promising performances were pointed out as 70 % of Diuron and 92 % of BPA can be removed from aqueous solution for an initial concentration respectively 35 mg/L and 20 mg/L, when the usual concentrations of BPA in environmental waters are in the range of 10 ng/L to 400 μg/L and Diuron is around 1 600 ng/L. This innovative process is based on valorization of agricultural waste biomass, of which billions of kilograms are produced annually, to low cost but efficient adsorbent that can contribute to environmental remediation.