Solvent free acetalization of glycerol with formaldehyde over hierarchical zeolite of BEA topology

The hierarchical H/BEA zeolites were prepared by postsynthesis treatment. The portion of the parent H/BEA zeolite was treated with aqueous 0.1 M NaOH solution with different alkali volume to H/BEA zeolite weight (5, 10, 30,150, and 300 mL/g) ratios. The physicochemical properties of samples were evaluated by powder X-ray diffraction, Pyridine Fourier transform infrared spectroscopy, NH3 temperature programme desorption, Nitrogen adsorption/desorption isotherms, and magic angle spinning nuclear magnetic resonance spectroscopy. The catalytic performance of various catalysts was investigated in solvent free acetalization of glycerol with formaldehyde. Among all the catalysts, a hierarchical H/BEA prepared by treating H/BEA with 5 mL aqueous 0.1 M NaOH solution per gram of H/BEA exhibited the highest specific surface area and high acidity. This optimal hierarchical H/BEA(5) catalyst has shown an excellent catalytic activity with glycerol conversion of 78% and 1,3 dioxalane selectivity of 85% under mild operating parameters than reported. H/BEA(5) was found to be highly stable and recyclable. The acetalization of glycerol with formaldehyde follows first order reversible using PseudoHomogeneous model. In present study, the activation energy for this reaction is found to be 46.95 KJmol(-1) which is lower than reported. (c) 2017 American Institute of Chemical Engineers Environ Prog, 37: 797-807, 2018