Sustainable regeneration of a honeycomb carbon aerogel used as a high-capacity adsorbent for Fluoxetine removal

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUG Pharmaceuticals and personal care products (PPCPs) harm ecosystems and human health. The focus is now being put on regulating discharges at wastewater treatment plants (WWTPs). Stressful and lonely lifestyles, accentuated by the COVID-19 outbreak, have led to an increase in the consumption of antidepressants, particularly in the form of Fluoxetine (FLX). A highly effective process for the removal of PPCPs is of key importance for the economic feasibility of the process in the industry. Consequently, a high-capacity adsorption/regeneration system is crucial to solving this problem. In this study, the removal of FLX by an adsorption process and the subsequent in situ regeneration of the adsorbent was evaluated in successive cycles. NQ40 honeycomb 3D carbon aerogel was employed as a high-capacity adsorbent, obtaining uptakes of 125.24 mg/g. A detailed study of NQ40 and the mechanisms governing the adsorption process was conducted, with chemisorption and intra-particle diffusion playing the main role. A Fenton and a Fenton-like process with peroxymonosulfate (PMS) were evaluated for regeneration purposes, finding hydrogen peroxide to be more efficient in removing a high concentration of FLX. A regeneration capacity of 98.85% was achieved in the first NQ40 adsorption-regeneration cycle and 98.04% in the second one, without negatively affecting the structural characteristics of NQ40. Therefore, with a high porosity, low density, high biocompatibility, high chemical stability and 3D structural stability, this aerogel is at the forefront of novel high-capacity adsorbent materials for industrial-scale use in WWTPs. Agencia Estatal de Investigación | Ref. PID2020-113667GB-I00 Agencia Estatal de Investigación | Ref. PDC2021-121394-I00 Xunta de Galicia | Ref. ED431C 2021-43