Skip to main content

Research Repository

Advanced Search

Sludge-derived biochar: Physicochemical characteristics for environmental remediation

Mayilswamy, Neelaambhigai; Nighojkar, Amrita; Edirisinghe, Mohan; Sundaram, Senthilarasu; Kandasubramanian, Balasubramanian


Neelaambhigai Mayilswamy

Amrita Nighojkar

Mohan Edirisinghe

Balasubramanian Kandasubramanian


The global production of fecal wastes is envisioned to reach a very high tonnage by 2030. Perilous handling and consequential exposition of human and animal fecal matter are inextricably linked with stunted growth, enteric diseases, inadequate cognitive skills, and zoonoses. Sludge treatment from sewage and water treatment processes accounts for a very high proportion of overall operational expenditure. Straightforward carbonization of sludges to generate biochar adsorbents or catalysts fosters a circular economy, curtailing sludge processing outlay. Biochars, carbonaceous substances synthesized via the thermochemical transformation of biomass, possess very high porosity, cation exchange capacity, specific surface area, and active functional sorption sites making them very effective as multifaceted adsorbents, promoting a negative carbon emission technology. By customizing the processing parameters and biomass feedstock, engineered biochars possess discrete physicochemical characteristics that engender greater efficaciousness for adsorbing various contaminants. This review provides explicit insight into the characteristics, environmental impact considerations, and SWOT analysis of different sludges (drinking water, fecal, and raw sewage sludge) and the contemporary biochar production, modification, characterization techniques, and physicochemical characteristics, factors influencing the properties of biochars derived from the aforestated sludges, along with the designing of chemical reactors involved in biochar production. This paper also manifests a state-of-the-art discussion of the utilization of sludge-derived biochars for the eviction of toxic metal ions, organic compounds, microplastics, toxic gases, vermicomposting approaches, and soil amelioration with an emphasis on biochar recyclability, reutilization, and toxicity. The practicability of scaling up biochar generation with multifaceted, application-accustomed functionalities should be explored to aggrandize socio-economic merits.

Journal Article Type Review
Acceptance Date Jul 25, 2023
Online Publication Date Aug 16, 2023
Publication Date 2023-09
Deposit Date Aug 18, 2023
Publisher AIP Publishing
Peer Reviewed Peer Reviewed
Volume 10
Issue 3
Article Number 031308
Keywords Biochar, Biomass energy sources, Edaphology, Water treatment, Porous media, Ions and properties, Carbonization, Catalysts and Catalysis, Toxicology, Antibiotics