Facile synthesis of mesoporous γ-alumina with tunable pore size: The effects of water to aluminum molar ratio in hydrolysis of aluminum alkoxides

• Published in: Microporous and mesoporous materials 2014-01, Vol.183, p.37-47
• Main Authors: Huang, Baiyu, Bartholomew, Calvin H., Woodfield, Brian F.
• Format: Article
• Language: English
• Subjects: Alumina alkoxides; Chemistry; Colloidal state and disperse state; Controlled pore propert; Exact sciences and technology; General and physical chemistry; Hydrolysis; Mesoporous; Porous materials
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2013.09.007

•Mesoporous gamma aluminas are synthesized via a one-pot, solvent deficient method.•By varying the H2O/Al molar ratio, pore size of the alumina supports can be tuned.•No template or surfactant is used.•The formation mechanism is discussed. We report a facile synthesis of mesoporous alumina catalysts supports which enables control of pore structure, including pore diameter, by controlled hydrolysis of aluminum alkoxides without addition of a template or structural directing agent. By employing low water to alumina molar ratios and varying this ratio from 2 to 15, we are able to synthesize γ-alumina catalyst supports with different pore structures. X-ray diffraction, transmission electron microscopy, nitrogen gas adsorption, and comparative adsorption analysis were performed to determine structures of these materials. After calcination at 700°C for 2h, surface areas of these synthesized alumina catalyst supports range from 240 to 320m2/g, average pore range from 4 to 18nm, and pore volumes range from 0.4 to 1.6cm3/g. Accordingly, this synthetic strategy provides a facile route to the controlled synthesis of nanostructured alumina catalyst supports with customized pore structures.