Lignin biopolymer-bound soil composite (BSC): a sustainable, recyclable, carbon-negative, construction material

Stanford University's Lepech Research Group has developed a sustainable, recyclable, carbon-negative construction material that binds soil with lignin, a natural biopolymer, instead of Portland cement. Biopolymer-bound soil composites (BSC) are formed by mixing soil aggregate, biopolymer, and solvent, then desiccating the mixture into a solid structural component. Lignin, a hydrophobic biopolymer abundant in regions with high cement demand, provides enhanced moisture resistance. Compared to Portland cement, lignin BSC requires less energy and heat, uses low-cost feedstocks, and unlike concrete, is explicitly recyclable.

Stage of Development – Prototype
The Lepech Research Group have produced standard clay-fired size bricks that meet strength requirements for non-structural construction applications as defined by ASTM.