Unburned material from biomass combustion as low-cost adsorbent for amoxicillin removal from wastewater

Ultimate and proximate analyses, HHV and BET surface area have been assessed in the unburned materials obtained by combustion in a conical spouted bed of four types of vegetable biomasses representative of forestry residues, grass and food industry. The results show that the materials are mainly of carbonaceous structure, which stems from the incomplete decomposition of cellulose and lignin, and their content decreases with combustion temperature. The unburned materials have a high surface area, which is of the same order as certain commercial active carbons, rendering them suitable properties for use as low-cost adsorbent. In order to verify this fact, removal efficiencies have been determined in amoxicillin removal tests, and the characteristic parameters, as well as mass transfer coefficients, have been calculated for two adsorption models following Langmuir and Freundlich isotherms. The results confirm that this byproduct obtained in the recovery of energy from waste biomass performs well in the removal of emerging pollutants from wastewater, and is a viable alternative of commercial adsorbents. (C) 2020 Elsevier Ltd. All rights reserved.