# Potential of Wood Processing Residues as Eco-Friendly Adsorbents for Wastewater Treatment

## TL;DR

This study explores using wood waste from furniture manufacturing as a low-cost, eco-friendly material to remove manganese from wastewater.

## Contribution

The novel contribution is evaluating raw wood shavings and their biochars as adsorbents for Mn(II) removal, emphasizing their potential in sustainable water treatment.

## Key findings

- Cherry wood shavings and biochars showed higher Mn(II) adsorption capacity than walnut wood materials.
- Physical activation improved surface properties and adsorption efficiency of the wood residues.
- Adsorption mechanisms suggest chemisorption on heterogeneous surfaces, fitting well with the pseudo second-order kinetic model.

## Abstract

In the context of global warming mitigation through energy conservation and pollution control, integrating green waste into treatment processes has become more popular. This study evaluated the potential of raw wood processing residues generated from furniture manufacturing as renewable sorbents for water treatment. Comparative studies assessed the Mn(II) removal efficiency of raw walnut (WW) and cherry (CW) wood shavings and the derived biochars (BChWW, BChCW) produced by hydropyrolysis. SEM, BET, FTIR, and TGA analyses characterized their surface and structural properties. CW demonstrated a higher adsorption capacity compared to WW. Physical activation enhanced the surface properties and Mn(II) adsorption affinity of the materials. Maximum adsorption capacities ranged from 2.1 to 2.2 mg/g for CW and WW, and 2.4 to 2.5 mg/g for BChCW and BChWW. The Freundlich model best fits to the data obtained using CW (R2 = 0.997) and BChCW (R2 = 0.984), while the RALF isotherm almost perfectly describes the mechanism of the Mn(II) adsorption onto WW (R2 = 0.999) and BChWW (R2 = 1.000). The pseudo second-order kinetic model shows strong agreement with experimental data, which suggests chemisorption on a heterogeneous surface. The results underscore the potential of wood industry byproducts as efficient and low-cost adsorbents for water treatment, supporting the circular economy and sustainable environmental management.