Greening of coffee waste through its transformation into clean and structurally stable activated carbon for energy storage applications.

ABSTRACT: The sustainable transformation of biomass waste into high-purity activated carbon (AC) offers a promising solution to environmental challenges while advancing material innovations. However, conventional methods often yield materials with limited purity and performance. This study presents a scalable process to produce high-purity AC (99.7 wt%) from spent coffee grounds using optimized alkaline infusion, acid etching, and thermal treatment. The process achieves near-complete removal of inorganic residues and metal oxides, significantly improving structural, compositional, and electrochemical properties. Alkaline infusion with a 1 : 1.5 biochar-to-NaOH ratio reduced ash content from ∼7.8 to <0.3 wt% and increased carbon content to 83.6 wt%. Acid etching further removed residual oxides such a

SUBMITTER: Abideen ZU 

PROVIDER: S-EPMC12548544 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature