Synthesis of novel acidic ionic liquid immobilized on silica

A novel acidic ionic liquid immobilized on silica has been synthesized by hydrolyzing tetraethyl orthosilicate (TEOS) and the acidic ionic liquid derived from (3-aminopropyl) trimethoxysilane. The catalytic activities were evaluated in the acetalization and biodiesel synthesis. The results showed that the solid acid was a very efficient catalyst for the traditional acid-catalyzed reactions with the yield over 99.0%. A novel solid acid combined both the high activities inherent to the acidic ionic liquid and the feasibility of separation of the solid catalysts. High acidity, enhanced catalytic activities and improved stability were the key properties of the novel solid acid.