Engineered biochar combined clay for microplastic biodegradation during pig manure composting.

Area of Science:

• Environmental Science
• Microbiology
• Materials Science

Background:

• Microplastic (MP) pollution is a growing environmental concern.
• Composting is a potential method for MP biodegradation.
• Walnut shell biochar (WSB) and montmorillonite (M) can influence composting processes.

Purpose of the Study:

• To investigate the effect of WSB and M on bacterial community succession during pig manure (PM) composting.
• To determine the optimal WSB concentration for expedited MP biodegradation.
• To analyze the chemical changes in MPs during composting with WSB.

Main Methods:

• Composting of PM with varying WSB (0-12%) and 10% M concentrations for 42 days.
• Analysis of bacterial community structure using high-throughput sequencing.
• Characterization of MP degradation using Energy Dispersive Spectrometer (EDS) and Fourier Transform Infrared Spectroscopy (FTIR).

Main Results:

• Bacterial communities were dominated by Firmicutes, Proteobacteria, Chloroflexi, and Bacteroidetes.
• WSB addition significantly altered bacterial community composition throughout composting.
• MP carbon content decreased by up to 20.25%, with reduced CC, C-O, C-H, and -COOH bonds at higher WSB doses.

Conclusions:

• WSB addition effectively regulates bacterial communities and enhances MP biodegradation during PM composting.
• Composting with optimal WSB concentrations offers a practical solution for mitigating MP pollution.
• The study demonstrates the potential of biochar-amended composting for environmental remediation.