Biochar produced from eggshell waste applied for removal of water-polluting substances and clayey soil stabilization: an environmental friendly application

This study aimed to evaluate biochar produced from eggshells to remove water-polluting substances and to apply it on clayey soil to improve physical properties. CCRD was used to determine the influence of biochar concentration and contact time in water-polluting substance removal. Bacteria removal efficiency and genotoxicity effects were evaluated. Compaction and compressive strength tests were performed after the application of biochar to clayey soils. The removal efficiency of aluminum, fluoride, manganese, zinc, and iron were 52.8, 69.8, 78.9, 96.7, and 96.4%, respectively. After 6 h of contact time, E. coli was completely removed. The water did not demonstrate genotoxic residual after biochar application. The maximum compressive strength obtained demonstrated an increase of 29.7% if compared to control. The biochar production from eggshell waste to remove water-polluting and stabilization of clayey soil provides a very simple, low-cost, effective and environmental friendly of this waste.