Consecutive Production of Hydroalcoholic Extracts, Carbohydrates Derivatives and Silica Nanoparticles from Equisetum arvense

摘要

Intelligent strategies should be used in biorefinery processes for the production of different high-value products from the same raw material. Focused on this, the biomass from Equisetum arvense (horsetail) was used for the consecutive production of an extract with medicinal properties, carbohydrate derivatives, heat energy and nanosilica. The biorefinery of horsetail involved a hydroalcoholic extraction, followed by acid hydrolysis and calcination. The yield of the hydroalcoholic extract was 20.2%; however, the yields of monomeric sugars, heat energy and silica varied with the conditions used in each step of the process. High-quality nanosilica could be obtained using mild acid hydrolysis conditions (120 degrees C, 1 h, H2SO4 center dot 2 wt%) followed by calcination at moderated temperature (650 degrees C); in this case, the yields of co-products were relatively low. However, such yields were increased by changing the hydrolysis temperature to 140 degrees C but the resulting silica nanoparticles had lower quality.