Performance Optimization and Carbon Reduction Potential of Bamboo Biochar for Lightweight Artificial Aggregates

作者：Haibao Liu, L. Wang X.X. Bu, Yulin Wang, Mingxu Chen, Dongdong Chen · 发表于：Materials · 年份：2025 · DOI：10.3390/ma18235415 · 研究领域：Thermochemical Biomass Conversion Processes、Concrete and Cement Materials Research、Hygrothermal properties of building materials

To realize the efficient utilization of biochar and construction solid waste in building materials production, a novel core–shell aggregate concept is proposed, in which artificial aggregates are prepared by encapsulating coarse-particle bamboo biochar (C-BB) with concrete slurry waste (CSW), calcium carbide slag (CCS), and fine-particle bamboo biochar (F-BB). The results showed that the best engineering properties of the artificial aggregates were achieved when the F-BB content was about 6%, with crushing strength, water absorption, and bulk density values of 4.7 MPa, 14.3%, and 796 kg/m3, respectively. In addition, the artificial aggregates have promising potential for CO2 uptake under a CO2 curing system and can achieve 5.72% (by mass) uptake when the F-BB content is 6%. This performance is attributed to the formation of well-developed CO2 transport channels in the shell matrix by the F-BB particles. In summary, the novel core–shell aggregate not only has better engineering properties than commercial lightweight aggregates but also offers significant potential for CO2 sequestration, opening new opportunities for the efficient application of biochar in construction materials with both engineering and environmental benefits.