Synthesis And Characterization Of The Organotin Compounds Tethered On Al-MCM-41

Al-MCM-41(n(Si):n(Al)=30:1)(AlM) and silanization Al-MCM-41 (n(Si):n(Al)=30:1) (SiAlM) materials were synthesized. AlM was modified by tributyltin chloride and trimethyltin chloride respectively, and SnTBAlM and SnTMAlM were got. SiAlM was grafted by tributyltin chloride and trimethyltin chloride respectively ether, SnTBSiAlM and SnTMSiAlM were got. The composition, structure and surface physical and chemical properties of the samples were characterized by X-ray EDS analysis, inductively coupled plasma mass spectrometry (ICP-MS), elemental analyzer, fourier transform infrared spectroscopy (FTIR), N₂ adsorption-desorption, NH₃ chemisorption (NH₃-TPD), small-angle X-ray diffraction (XRD), scanning electronic microscope (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TG) and so on.The results of ICP and organic elemental analysis showed that the grafting yield were 6.46% and 6.79% of Sn(w%) for SnTBAlM and SnTBSiAlM respectively. The samples had the ordered hexagonal mesopore structure and ordered arrangement with the shape of worm-like. The BET surface area, pore volume, bore diameter, TPD acid of SnTBAlM reached 1202 m²/g, 0.7490 mL/g, 2.492 nm, 1.4889 mmol/g respectively. The BET surface area, pore volume, bore diameter, TPD acid of SnTBSiAlM reached 1037 m²/g, 0.6916 mL/g, 2.668 nm, 3.0565 mmol/g respectively.The results of ICP and organic elemental analysis showed that the grafting yield were 10.44% and 7.21% of Sn(w%) for SnTMAlM and SnTMSiAlM respectively. The samples had the ordered hexagonal mesopore structure and ordered arrangement with the shape of worm-like. The BET surface area, pore volume, bore diameter, TPD acid of SnTMAlM reached 704.3 m²/g, 0.4947 mL/g, 2.809 nm, 1.4731 mmol/g respectively. The BET surface area, pore volume, bore diameter, TPD acid of SnTMSiAlM reached 1087 m²/g, 0.7952 mL/g, 2.927 nm, 2.9317 mmol/g respectively.Catalytic character of SnTBAlM and SnTBSiAlM sieve were evaluated using esterification reaction of isoamyl alcohol and acetic acid as a probe. The results showed that both of SnTBAlM and SnTBSiAlM molecular sieve had high catalytic activity in synthesis of iso-amyl acetate. When n (isoamyl alcohol): n (acetic acid) = 1.0:1.0, the reaction time for 5 h and the amount of catalyst (w %)= 5%, the esterification yield of SnTBAlM and SnTBSiAlM reached 96.88% and 97.32% respectively. The reuse of SnTBAlM and SnTBSiAlM molecular sieve was researched respectively. When the catalysts were used four times repeatly, the esterification yield of the former was still approach 86.56%, the esterification yield of the latter was 79.04%.