Microbial-Plant-Biochar System for the Removal of Pollutants from Effluents and Contaminated Soil

Zainab; Alisha Iqbal; Aqsa Sakhawat; Muhammad Umer Sajid; Aroosa Bibi; Ayesha Siddiqa

Authors

Zainab Institute of Microbiology and Molecular Genetics, University of Punjab, Lahore
Alisha Iqbal Institute of Microbiology and Molecular Genetics, University of Punjab, Lahore
Aqsa Sakhawat Institute of Microbiology and Molecular Genetics, University of Punjab, Lahore
Muhammad Umer Sajid Institute of Microbiology and Molecular Genetics, University of Punjab, Lahore
Aroosa Bibi Institute of Microbiology and Molecular Genetics, University of Punjab, Lahore
Ayesha Siddiqa Institute of Microbiology and Molecular Genetics, University of Punjab, Lahore

Keywords:

Sludge, Microbial-Biochar System, Pyrolysis, Immobilization, Bioreactor System

Abstract

Industrial activities released wastewater containing heavy metals and synthetic dyes that remain in the environment for a longer period. These pollutants disrupt ecosystems, pose risks to human health, and continue to accumulate if they are not treated properly. Many conventional remediation methods are costly and often generate secondary waste, which limits their practical use. As a result, researchers are increasingly exploring sustainable and environmentally friendly alternatives. This review discusses an integrated-microbial-biochar system as a promising approach for wastewater and soil remediation. Biochar produced from materials such as sewage sludge, oil-field drilling mud, and agricultural residues offers a highly porous and chemically active surface that can effectively bind heavy metals (Cd, Cu, and Zn) as well as a wide range of industrial dyes. In addition, microbial strains such as Acinetobacter sp. and Bacillus subtilis play an important role in degrading organic pollutants, restoring enzymatic activity and contaminated soils, and improving nutrient cycling. Recent developments, including biochar-microbe beads and composite bioreactor systems, have shown better performance than biochar or microbes used alone. These combined systems enhance microbial survival, reduce toxicity, and significantly improve pollutant removal efficiency. By summarizing recent findings on pyrolysis conditions, microbial immobilization techniques, and pollutant removal behavior, this review highlights the potential of hybrid remediation strategies. Emerging modifications, such as magnetic chitosan-modified biochar, are also discuss future directions to further strengthen integrated remediation systems.

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