Adsorption-desorption of phenolic compounds from olive mills wastewater using Tunisian natural clay

Olive mills wastewater (OMW) exhibit substantial contaminated properties due to their content of phenolic constituents and organic substances. The purpose of this work was the investigation of the efficiency of clay materials for the adsorption of phenolic compounds, which are contained in OMW. Furthermore, thermal activation of the clay took place in order to improve phenolic compounds uptake and afterwards, desorption process was studied. The adsorbent was characterized using XRD, XRF and BET surface area analyses. The adsorption efficiency of phenolic compounds by raw and calcined clay at 600 degrees C was 77.61% and 84.21%, respectively at acidic pH. The values of Gibbs free energy indicated that adsorption process is spontaneous and beneficial at higher temperatures. Alkaline medium was propitious for phenolic compounds desorption. The obtained results showed that natural clay could be used as a low-cost adsorbent for OMW treatment. (C) 2021 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

Automated summary

This study investigated the efficiency of clay materials for the adsorption of phenolic compounds in olive mills wastewater (OMW). The results showed that raw and calcined clay exhibited good adsorption efficiency, especially at acidic pH. Thermal activation of the clay improved the uptake of phenolic compounds, making it a promising low-cost adsorbent for OMW treatment.