The purpose of this study was to evaluate the feasibility studies on the production of silica from agricultural wastes (i.e. rice husk, rice straw, bagasse, and corn cob) from engineering and economic perspectives. The engineering perspective was done by calculating stoichiometry, mass balance, and the preliminary plant design evaluation, whereas the economic perspective analysis was performed by calculating various economic parameters (i.e., Gross Profit Margin, Internal Rate Return, Break Even Point, Payback Period, and Cumulative Net Present Value) under various conditions. The results from engineering perspective showed that the project is applicable even in the home-scale production. The project is potentially scaled up since it can be executed using commercially available and inexpensive equipment. Economic analysis showed that various agricultural wastes gave positive impacts on profitability, confirmed by the various economic evaluation parameters. Based on the evaluation from various agricultural wastes, rice husk is the best raw materials for gaining the highest interest, whereas corn cob is the worst. To confirm the analysis, various economic conditions under different raw material costs, utility costs, labor, and sales, as well as taxes, were added into the calculation, and they showed positive values for the potential production of silica particles. Although the evaluation confirmed for the excellent economic parameter values, further analysis of this project must be carried out to determine the uncertainty of conditions existing during the realistic project
