Preparation of 3,4-dihydro-2H-pyran catalyzed by modified gamma alumina

Abstract

A promising catalytic material, modified gamma alumina with high surface area (300 m²/g) and higher contents of strong acid sites was developed. It was prepared by a special precipitation method with aluminum nitrate solution containing a certain amounts of orthosilicic acid and ammonia aqueous solution. Compared with commercial gamma alumina, the modified gamma alumina is an effective catalyst for dehydration of tetrahydrofurfuryl alcohol to 3,4-Dihydro-2 H-pyran. Under the optimized reaction conditions, an improved yield of 3, 4-Dihydro-2H-pyran of 93.4% was achieved. The profiles of pyridine TPD show that the modified gamma alumina exhibits more strong acid sites than that in the commercial gamma alumina, indicating the strong acid sites on the surface of the catalyst may play a crucial role in this reaction.

Keywords

catalytic material / gamma alumina / 3,4-Dihydro-2H-pyran / pyridine TPD

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