Zeolites as heterogeneous catalysts to valorization of monoterpenes into flavors and fragrances

Abstract

Zeolites are aluminosilicate with high surface area and uniform microporosity. Monoterpenes are renewable resources. The catalytic transformation of terpenes are synthetic routes to valuable compounds. Strong homogeneous acid catalysts have been used in the acid reactions. Due to enviromental problems, homogeneous catalysts have been replaced by heterogeneous catalysts, which are reusable and easy to be separated from liquid products. Zeolites have been used as heterogenous catalysts on different reactions with terpenes, like isomerization, hydration, acetoxylation and alkoxylation. This present review focuses on zeolites as potential heterogeneous catalysts for terpenes valorisation into fragrances and flavours, replacing the homogenous catalysts. It is also studied the hydration of beta-pinene over zeolites (USY, Beta and ZSM-5).