A Mini-Review of Sludge-Derived Biochar (SDB) for Wastewater Treatment: Recent Advances in 2020–2025

Sludge-derived biochar (SDB) synthesized by the pyrolysis of sludge is gaining enormous interest as a sustainable solution to wastewater treatment and sludge disposal. Despite the proliferation of general biochar reviews, a focused synthesis on SDB-specific advances, particularly covering the recent...

Full description

Saved in:
Bibliographic Details
Main Authors: Lia Wang, Lan Liang, Ning Li, Guanyi Chen, Haixiao Guo, Li’an Hou
Format: Article
Language:English
Published: MDPI AG 2025-05-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/15/11/6173
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849330793470492672
author Lia Wang
Lan Liang
Ning Li
Guanyi Chen
Haixiao Guo
Li’an Hou
author_facet Lia Wang
Lan Liang
Ning Li
Guanyi Chen
Haixiao Guo
Li’an Hou
author_sort Lia Wang
collection DOAJ
description Sludge-derived biochar (SDB) synthesized by the pyrolysis of sludge is gaining enormous interest as a sustainable solution to wastewater treatment and sludge disposal. Despite the proliferation of general biochar reviews, a focused synthesis on SDB-specific advances, particularly covering the recent surge in multifunctional wastewater treatment applications (2020–2025), receives little emphasis. In particular, a critical analysis of recent trends, application challenges, and future research directions for SDB is still limited. Unlike broader biochar reviews, this mini-review highlights the comparative advantages and limitations of SDB, identifies emerging integration strategies (e.g., bio-electrochemical systems, catalytic membranes), and outlines future research priorities toward enhancing the durability and environmental safety of SDB applications. Specifically, this review summarized the advances from 2020 to 2025, focusing exclusively on functional modifications, and practical applications of SDB across diverse wastewater treatment technologies involved in adsorption, catalytic oxidation, membrane integration, electrochemical processes and bio-treatment systems. Quantitative comparisons of adsorption capacities (e.g., >99% Cd2+ removal, >150 mg/g tetracycline adsorption) and catalytic degradation efficiencies are provided to illustrate recent improvements. The potential of SDB in evaluating traditional and emerging contaminant degradation among the Fenton-like, persulfate, and peracetic acid activation systems was emphasized. Integration with membrane technologies reduces fouling, while electrochemical applications, including microbial fuel cells, yield higher power densities. To improve the functionality of SDB-based systems in targeting contamination removal, modification strategies, i.e., thermal activation, heteroatom doping (N, S, P), and metal loading, played crucial roles. Emerging trends highlight hybrid systems and persistent free radicals for non-radical pathways. Despite progress, critical challenges persist in scalability, long-term stability, lifecycle assessments, and scale-up implementation. The targeted synthesis of this review offers valuable insights to guide the development and practical deployment of SDB in sustainable wastewater management.
format Article
id doaj-art-176a1ae03cac49b3b5699d9cbedaafb8
institution Kabale University
issn 2076-3417
language English
publishDate 2025-05-01
publisher MDPI AG
record_format Article
series Applied Sciences
spelling doaj-art-176a1ae03cac49b3b5699d9cbedaafb82025-08-20T03:46:48ZengMDPI AGApplied Sciences2076-34172025-05-011511617310.3390/app15116173A Mini-Review of Sludge-Derived Biochar (SDB) for Wastewater Treatment: Recent Advances in 2020–2025Lia Wang0Lan Liang1Ning Li2Guanyi Chen3Haixiao Guo4Li’an Hou5School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, ChinaSchool of Environmental Science and Engineering, Tianjin University, Tianjin 300072, ChinaSchool of Environmental Science and Engineering, Tianjin University, Tianjin 300072, ChinaSchool of Environmental Science and Engineering, Tianjin University, Tianjin 300072, ChinaSchool of Mechanical Engineering, Tianjin University of Commerce, Tianjin 300134, ChinaSchool of Environmental Science and Engineering, Tianjin University, Tianjin 300072, ChinaSludge-derived biochar (SDB) synthesized by the pyrolysis of sludge is gaining enormous interest as a sustainable solution to wastewater treatment and sludge disposal. Despite the proliferation of general biochar reviews, a focused synthesis on SDB-specific advances, particularly covering the recent surge in multifunctional wastewater treatment applications (2020–2025), receives little emphasis. In particular, a critical analysis of recent trends, application challenges, and future research directions for SDB is still limited. Unlike broader biochar reviews, this mini-review highlights the comparative advantages and limitations of SDB, identifies emerging integration strategies (e.g., bio-electrochemical systems, catalytic membranes), and outlines future research priorities toward enhancing the durability and environmental safety of SDB applications. Specifically, this review summarized the advances from 2020 to 2025, focusing exclusively on functional modifications, and practical applications of SDB across diverse wastewater treatment technologies involved in adsorption, catalytic oxidation, membrane integration, electrochemical processes and bio-treatment systems. Quantitative comparisons of adsorption capacities (e.g., >99% Cd2+ removal, >150 mg/g tetracycline adsorption) and catalytic degradation efficiencies are provided to illustrate recent improvements. The potential of SDB in evaluating traditional and emerging contaminant degradation among the Fenton-like, persulfate, and peracetic acid activation systems was emphasized. Integration with membrane technologies reduces fouling, while electrochemical applications, including microbial fuel cells, yield higher power densities. To improve the functionality of SDB-based systems in targeting contamination removal, modification strategies, i.e., thermal activation, heteroatom doping (N, S, P), and metal loading, played crucial roles. Emerging trends highlight hybrid systems and persistent free radicals for non-radical pathways. Despite progress, critical challenges persist in scalability, long-term stability, lifecycle assessments, and scale-up implementation. The targeted synthesis of this review offers valuable insights to guide the development and practical deployment of SDB in sustainable wastewater management.https://www.mdpi.com/2076-3417/15/11/6173sludge-derived biocharwastewatermodification strategiescontaminantsadvanced oxidation process
spellingShingle Lia Wang
Lan Liang
Ning Li
Guanyi Chen
Haixiao Guo
Li’an Hou
A Mini-Review of Sludge-Derived Biochar (SDB) for Wastewater Treatment: Recent Advances in 2020–2025
Applied Sciences
sludge-derived biochar
wastewater
modification strategies
contaminants
advanced oxidation process
title A Mini-Review of Sludge-Derived Biochar (SDB) for Wastewater Treatment: Recent Advances in 2020–2025
title_full A Mini-Review of Sludge-Derived Biochar (SDB) for Wastewater Treatment: Recent Advances in 2020–2025
title_fullStr A Mini-Review of Sludge-Derived Biochar (SDB) for Wastewater Treatment: Recent Advances in 2020–2025
title_full_unstemmed A Mini-Review of Sludge-Derived Biochar (SDB) for Wastewater Treatment: Recent Advances in 2020–2025
title_short A Mini-Review of Sludge-Derived Biochar (SDB) for Wastewater Treatment: Recent Advances in 2020–2025
title_sort mini review of sludge derived biochar sdb for wastewater treatment recent advances in 2020 2025
topic sludge-derived biochar
wastewater
modification strategies
contaminants
advanced oxidation process
url https://www.mdpi.com/2076-3417/15/11/6173
work_keys_str_mv AT liawang aminireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT lanliang aminireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT ningli aminireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT guanyichen aminireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT haixiaoguo aminireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT lianhou aminireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT liawang minireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT lanliang minireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT ningli minireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT guanyichen minireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT haixiaoguo minireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025
AT lianhou minireviewofsludgederivedbiocharsdbforwastewatertreatmentrecentadvancesin20202025