Transformative innovations in nano-biochar-enhanced porous concrete: Elevating engineering performance and pollutant removal

Abstract

This study addresses a significant gap in research by exploring the integration of nano-biochar (NBC) into porous concrete (PC) to enhance water purification capabilities while also evaluating its impact on the material's physical and mechanical properties. NBC was added in varying weights (0%–100%) to the binder material. Notably, beyond 10% NBC content, there was a significant reduction (p < 0.05) in porosity and compressive strength. Microstructural analyses using SEM, XRD, and FTIR revealed the incorporation of C–S–H within NBC pore structures. At 50% NBC content, substantial removal efficiencies (p < 0.05) were observed for manganese (Mn), nitrate (NO3−), total phosphorus (TP), and atrazine (AZ), reaching values of 97.4%, 93.9%, 97.3%, and 52.9%, respectively. Linear regression models revealed significant relationships between the degree of NBC enhancement and the efficiency of Mn and AZ removal. The logarithmic function provided the most accurate predictions for the quantity of NO3− and TP adsorbed by PC. These findings demonstrated that NBC-enhanced PC offers improved environmental remediation and provides guidelines for optimizing its composition for specific pollutants. Balancing mechanical and environmental performance, highlighting its potential as a sustainable construction material that meets both structural and pollution control needs is recommended.