Catalytic activity of mesoporous Ga-SBA-15 materials in α-pinene isomerisation: Similarities and differences with Al-SBA-15 analogues

• Published in: Applied catalysis. A, General Vol. 368; no. 1; pp. 132 - 138
• Main Authors: Launay, F., Jarry, B., Bonardet, J.L.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 31.10.2009; Elsevier
• Subjects: Camphene; Catalysis; Chemistry; Colloidal state and disperse state; Direct synthesis; Exact sciences and technology; Ga-SBA-15; General and physical chemistry; Grafting; Limonene; Pinene isomerisation; Porous materials; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Limonene; Camphene; Direct synthesis; Ga-SBA-15; Pinene isomerisation; Grafting; 1,8-p-Menthadiene; Catalytic reaction; Similarity; Isomerization; Conversion; Porous material; Mesoporosity; Solid; Heterogeneous catalysis; Synthesis; Pinene
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2009.08.022

Performances of Ga-SBA-15 materials with different Si/Ga ratios prepared either by grafting or direct synthesis are compared with those of Al-SBA-15 analogues. Undeniably Ga-SBA-15 solids allow better yields of camphene + limonene and limit the production of heavy undesirable by-products. After a thermal treatment, recycled Ga-SBA-15 solids turn out to be as active as the fresh catalyst. A complete investigation of the catalytic activity of Ga-SBA-15 materials in α-pinene isomerisation is presented here. The performances of solids with different Si/Ga ratios prepared either by grafting or direct synthesis are compared with those of Al-SBA-15 analogues. In the case of Ga samples prepared by direct synthesis, α-pinene conversion can reach 90%, in relatively mild experimental conditions (353 K, 1 h). Camphene and limonene represent more than 50% of the products formed. In the case of samples prepared by post-synthesis, α-pinene conversion decreases with the Ga content, but remains much higher than with the corresponding Al-SBA-15 materials. In this latter case, heavy compounds are the main products and can correspond to more than 50% of the isomerised α-pinene. Undeniably Ga-SBA-15 solids allow better yields of camphene + limonene and limit the production of heavy undesirable by-products.