Biomass-based materials for estrogens adsorption from water: production methods and their characterization

Activated carbons (ACs) are low-cost carbonaceous materials with a high surface area ranging from 500 to 3000 m2/g. ACs are produced by pyrolysis that consists of the combustion of organic matter above 500 °C in the absence of oxygen, to have the breaking of carbonic bonds and formation of porosity in the material. ACs are also undergo an activation process in order to increase its adsorption performance. Activation can be performed only by physical treatment, in which the organic material is thermal treated with an atmosphere of air, CO2, and water vapor, or also by applying some chemical treatments using generally, strong acids, chloride salts or strong bases [1, 2]. As carbon source for ACs preparation, many precursors have been tested, mainly biomass wastes (olive stones, rice husk, coconut shell, among others) [2]. According to the Instituto Nacional de Estatística (INE), in 2021 Portugal produced more than 1.3 million tons of olives and it is estimated that more than 500,000 tons of residues were generated per year [3]. This work aims to investigate different production methods of ACs from olive stones change and their effects on the characteristics of the resultant adsorbentsThe authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2021)