Work

Addressing Europe’s new hunger for sustainable activated carbon in wastewater treatment: Micropollutant removal with residual wood-based adsorbents using different activation strategies

Year: 2025

Type: article

Abstract: To meet the recast EU Urban Wastewater Treatment Directive, the EU and Austria will require approx. 270 and 10 kt a −1 of activated carbon, respectively. This study explores the potential of using non-fossil activated carbon derived from residual woody biomass to fulfil this demand using experimental adsorption data. We compared a commercial activated carbon (COM-AC) with three activated carbons produced from local residual wood (ZINC-AC, G-AC, CO2-AC) using various activation strategies. ZINC-AC was produced through one-step chemical impregnation with ZnCl 2 of waste wood. G-AC was a by-product of gasifying forestry residue biomass, and CO2-AC is the CO 2 -activated version of G-AC. Adsorption experiments were performed with a mix of six micropollutants in different water matrices. ZINC-AC exhibited the highest surface area (S BET 1946 m 2 g −1 ) and the second highest micropollutant capacity in tap water (257.4 mg g −1 ), after COM-AC (297.6 mg g −1 ). ZINC-AC's capacity remained stable in wastewater. G-AC showed a low capacity (34.6 mg g −1 ), which could be increased to 105.1 mg g −1 by CO 2 -activation. The predominant removal mechanisms are identified as hydrophobic and π-interactions. The study suggests that these activated carbons from residual woods could be a viable alternative for wastewater treatment, though production yield (35 % vs. 3.5 % for the most promising methods) and quality will be crucial for assessing Europe’s activated carbon production potential from woody biomasses. • Three ACs from residual woody biomass: waste wood and forestry residue biomass. • High S BET of AC (1942 m 2 g −1 ) by chemical activation of waste wood. • Accumulated micropollutant adsorption capacity of up to 257.4 mg g −1 . • Forecast EU-wide AC demand of 270 kt a −1 – EU supply potential controlled by yield.

Source: Process Safety and Environmental Protection

DOI: 10.1016/j.cherd.2025.03.021