Feasibility of incorporating biopolymer‐stabilized chromium‐contaminated soil as fine aggregate in concrete

Abstract Heavy metal pollution due to fast industrialization causes severe threats to water bodies and the soil environment. Remediating chromium‐contaminated soil using conventional chemical, physical and biological methods is highly tedious, especially when a site is contaminated on a large scale. The present study explores the solidification and stabilization of chromium‐contaminated soil using a waste‐derived chitosan biopolymeric composite. Further, chitosan‐stabilized soil was utilized for the preparation of M25 concrete cubes. The results revealed that the compressive strength of the concrete cubes prepared with chromium‐contaminated soil and biopolymeric composite showed a 40% increment in strength at 20% replacement of solidified soil (by weight) compared to the pristine concrete cubes. The incorporation of chitosan in the chromium‐contaminated soil enhanced the binding within the concrete matrix, contributing to improved compressive strength. The toxicity characteristics leaching procedure (TCLP) studies of the concrete cubes prepared with the stabilized soil showed that the chromium concentration released from the cubes is negligible, which is 99% lesser than the chromium leached from the cubes prepared using unstabilized chromium‐contaminated soil. Further, this study highlights the potential for utilizing contaminated soil in concrete applications, thereby supporting circular economy principles; however, a comprehensive life cycle and cost assessment is required to fully evaluate its environmental and economic feasibility.