Hierarchical Diatomite-Based Pt–Ga Catalysts for Nonoxidative Propane Dehydrogenation

Abstract

The diatomite-based hierarchical Pt–Ga catalysts for nonoxidative propane dehydrogenation are synthesized by wetness impregnation method. Hydrothermal diatomite treatment with NaOH and cetyltrimethylammonium bromide (CTAB) leads to a partial diatomite dissolution with self-assembly of MCM-41 fragments inside the diatomite pores. The resulting MCM-41@diatomite composite materials exhibit a hierarchical porous architecture combining wide meso- and macropores (10–500 nm) from diatomite and thin mesopores (3–4 nm) of the MCM-41 material. Such structural features provide a high specific surface area making these materials promising as catalyst supports for high-temperature reactions, including propane dehydrogenation. The synergy between Pt and Ga oxide in propane dehydrogenation can be attributed to the possible formation of bimetallic Pt–Ga species under reductive conditions of the catalytic process.