Inherently Functionalized Carbon from Lipid and Protein-Rich Biomass to Reduce Ultraviolet-Induced Damages in Bituminous Materials

This paper examines the merits of using an inherently functionalized carbon, referred to as biochar as a free radical scavenger. The biochar was made from thermochemical liquefaction of a blend of algae (rich in protein and nucleic acids) and manure (rich in lipid). Here, we studied biochar's efficacy as a free-radical scavenger and ultraviolet blocker to qualify it as an anti-aging additive in construction, including roofing shingles made from the bituminous composite. The study's results show that the addition of biochar to bitumen significantly reduced the aging of bitumen. All tested biochars made from various relative proportions of algae and swine manure were found to be effective at reducing the extent of aging; however, the biochar made from algae alone was the most effective. The algal biochar was found to be an effective antiaging additive delaying aging up to 36%, as evidenced by lower rheology and the chemistry-based aging index compared to those of control bitumen after being exposed to the same aging protocol. Algal biochar was found to be more effective than other studied biochar scenarios owing to its inherently functionalized nature. The latter result could be attributed to the high surface area and rich phenol functional groups in algal biochar, turning it into an effective free-radical scavenger. The study outcome highlights the applicability of this inherently functionalized carbon referred to as biochar in construction to enhance sustainability while promoting the circular economy and the biomass value chain.