Microstructure and durability performance of sustainable cementitious composites containing high-volume regenerative biosilica

To promote diatom-based biofuel productions in clean energy, this paper explores the potential of using biosilica as a renewable and regenerative byproduct from diatom-based biofuel production in cementitious materials. High-purity diatomite (DE), a biosilica model compound, is selected to investigate the microstructure and durability performance of diatom-based cementitious composites. The replacement of portland cement with 30 wt.% DE significantly enhances the resistance to leaching, reduces the rapid chloride permeability, but increases the drying shrinkage at early ages. The microstructure of DE-containing matrix is refined due to the lime-silica reaction, and the interfacial transition zone of DE-containing concrete is densified. Overall, the DE-induced microstructural changes enhance the durability performance of DE-containing cementitious composites, which in turn demonstrates the feasibility of using biosilica as a sustainable cement substitute. The use of biosilica from diatom-based biofuel production can potentially reduce the CO2 emissions of carbon-intensive concrete production and promote the development of clean energy.

Automated summary

This paper explores the potential of using biosilica as a byproduct from diatom-based biofuel production in cementitious materials. The study finds that replacing some portland cement with biosilica can improve the durability performance of the materials, although it may increase drying shrinkage. The research also demonstrates the feasibility of using biosilica as a sustainable cement substitute.