Hydrochar from Spent Coffee Ground as a Sustainable Adsorbent for Dye Removal from Water: Adsorption Characterization and Improvement via Soft Alkaline Activation

Biomass 2026 Open access

Read full text
Authors: Gennaro Pace, Gianluigi Farru, Fabiano Asunis, Giovanna Cappai, Angela De Bonis, Maria Cristina Mascolo, Donatella Caniani, Ignazio Marcello Mancini, Salvatore Masi, Francesco Di Capua
DOI: 10.3390/biomass6010006
Cited by: 1
References: 29

Abstract

Spent coffee grounds (SCGs) are abundantly produced worldwide as a by-product of coffee brewing, and production is surging following the rise in global coffee consumption. Although the adsorption properties of raw SCGs have been investigated in previous studies, limited attention has been paid to the use of SCG-derived hydrochars as engineered adsorbents. In this work, hydrochars produced via hydrothermal carbonization (HTC) of SCGs at different temperatures were systematically assessed for their capacity to remove methylene blue (MB) dye from aqueous solution. The effect of HTC temperature and soft alkaline activation on MB adsorption were evaluated through adsorption batch tests. The soft alkaline activation increased the experimental adsorption capacity from

Fields of Study & Subjects

Adsorption and biosorption for pollutant removal Coffee research and impacts Supercapacitor Materials and Fabrication

Publication details

Journal / source
Biomass
Publisher
MDPI AG
Volume
6
Issue
1
Pages
6–6
Publication date
7 January 2026
Language
EN