A new solid acid SO42-/TiO2 catalyst modified with tin to synthesize 1,6-hexanediol diacrylate

A new solid acid catalyst, SO42-/TiO2 modified with tin, was prepared using a sol-gel method and its physicochemical properties were revealed by nitrogen adsorption-desorption, X-ray powder diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, infrared spectroscopy of adsorbed pyridine, temperature-programmed desorption of ammonia and thermal gravimetric analysis. The structure, acidity and thermal stability of the SO42-/TiO2-SnO2 catalyst were studied. Incorporating tin enlarged the specific surface area and decreased crystallite size of the SO42-/TiO2 catalyst. The total acid sites of the modified catalyst increased and Bronsted acid strength remarkably increased with increasing tin content. The decomposition temperature of sulfate radical in the modified catalyst was 100 degrees C greater and its mass loss was more than twice that of the SO42-/TiO2 catalyst. The SO42-/TiO2-SnO2 catalyst was designed to synthesize 1,6-hexanediol diacrylate by esterification of 1,6-hexanediol with crylic acid. The yield of 1,6-hexanediol diacrylate exceeded 87% under the optimal reaction conditions: crylic acid to 1,6-hexanediol molar ratio = 3.5, catalyst loading = 7%, reaction temperature = 130 degrees C and reaction time = 3 h. The modified catalyst exhibited excellent reusability and after 10 cycles the conversion of 1,6-hexanediol was above 81%. (C) 2016, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.