Innovative Mycelium Bio-Composites (MB) from Birch Sanding Dust and Chitosan with Enhanced Heavy Metals Sorption...

Chitosan is a well-known heavy metal biosorbent and was incorporated into birch sanding dust mycelium bio-composites (MBs). The chitosan-hybridized MBs with different chitosan contents were characterized by microscopy, porous structure analyses (specific surface area and total pore volume), pH_pzc, functional group content, and FTIR. Microscopy did not reveal any antifungal effect of chitosan on Trametes versicolor. The porous structure of the MBs decreased after hybridization with chitosan. The FTIR spectra and functional group analyses confirmed the presence of chitosan amino groups in the MBs. The chitosan-hybridized MBs were subjected to the adsorption of heavy metals, namely Cu(II) and Cd(II), and the removal percentage and adsorption isotherms were evaluated. Adsorption isotherms were analyzed using the Freundlich and Langmuir models. The results showed a significant increase in the maximum monolayer adsorption capacity for Cu(II), calculated using the Langmuir equation, from <2 mg/g for raw BSD and basic MB without chitosan to 19 mg/g for the MB with 15% chitosan. In the case of Cd(II), no significant increase in adsorption capacity was observed. These findings indicate that hybridization of MBs with chitosan is a promising approach to improve the Cu(II) adsorption capacity of MBs.