Synthesis of silica/carbon composite from agricultural waste as heterogeneous acid catalysts to produce dioxolane moieties from a biodiesel-derived waste compound

Silica/carbon composites from the carbonization of rice husk have been employed to act asheterogeneous Brønsted acid catalysts. These composites have been used to catalyze theacetalization of phenylacetaldehyde, vanillin, and 2-acetonaphthone with propylene glycol toproduce hyacinth, vanilla, and orange blossom scent fragrances. As the carbonization temperaturesaffect the physicochemical properties and hence their catalytic activity, several characterizationtechniques and data manipulation have been performed to understand the correlations. Acid densityand hydrophilicity has been proved to play a crucial part to obtain an optimized yield of desiredproducts.