Crop Residues as Potential Sustainable Precursors for Developing Silica Materials: A Review

Abstract: Prospecting for sustainable resources will be feasible to generate silica materials extensively used for various commercial applications. Accumulated amorphous silica, called phytolith, is found in the crop residues removed during the harvesting process. Hence, it will be beneficial to understand the potential for various kinds of crop residues used as silica production resource regarding their global generation, yield of generation, and enhancement using silicon fertilizer. Of the many crop residues discussed in this study, sugarcane leaves are the most useful potential silica source. Various synthesis methods are continuously developed with the expectation to achieve tunable silica particle properties with high processing efficiency. The applications for silica particles derived from crop residues vary depending on their unique characteristics related to textural and morphological properties. Silica materials developed from crop residues present several challenges involving silica depletion in croplands, segregation of valuable components from crop residues, and the high utilization of high energy and chemical reagents. Utilizing industrial wastes containing silica can be promoted as Si fertilizer to heal silica depletion in croplands. An integrated approach can be conducted applying low energy with fewer chemical methods to recover energy, lignocellulosic materials, carbonaceous materials, and siliceous material from crop residues, simultaneously. Graphic Abstract: [Figure not available: see fulltext.]