In a study published in Next Sustainability, Bhakta et al. report on an efficient technique to create nickel particles supported on maple wood biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More to form a magnetic nanocomposite. This nanocomposite can remove dyes like methyl orange (MO) and rhodamine B (RhB) from water. The methodology involves wet impregnation with aqueous nickel nitrate solution followed by pyrolysisPyrolysis is a thermochemical process that converts waste biomass into bio-char, bio-oil, and pyro-gas. It offers significant advantages in waste valorization, turning low-value materials into economically valuable resources. Its versatility allows for tailored products based on operational conditions, presenting itself as a cost-effective and efficient More at 500°C.  

The process resulted in homogeneously and uniformly distributed irregular shaped nickel particles, sized between 16-68 nm, on the biochar surface. The resulting material is shown to respond to a magnetic field. The magnetic nanocomposites were successfully used for the removal of RhB and MO from aqueous solutions. The adsorption capacity for RhB was found to be 54.21 mg/g. After the first, second, and third cycles, the reusability test of the adsorbent showed 99.41%, 74.58%, and 49.78% adsorption efficiency, respectively.  

The use of synthetic dyes has become very common in many industries, resulting in significant water pollution. Various materials have been employed for the adsorption of dyes, including biochar. Biochar has advantages, including high surface area, surface charge, tunable functional groups, water holding capacityWater holding capacity is the amount of water that soil can retain. Biochar can significantly increase the water holding capacity of soil, improving its ability to withstand drought conditions and support plant growth.   More, and porosityPorosity of biochar is a key factor in its effectiveness as a soil amendment and its ability to retain water and nutrients. Biochar’s porosity is influenced by feedstock type and pyrolysis temperature, and it plays a crucial role in microbial activity and overall soil health. Biochar More. This study demonstrates that biochar can be used to create filters for treating wastewater coming from textile industries.  

SOURCE: Bhakta, A. K., Znaidi, L., Blanc, E., Challab, N., Decorse, P., Gonzalez, A. V., Ammar, S., & Prasanna, S. (2025). Maple wood biochar-supported nickel nanoparticles: One pot synthesis for simultaneous removal of cationic and anionic dye mixture. Next Sustainability, 6, 100124.