ENHANCEMENT OF ACIDITY AND CATALYTIC ACTIVITY OF ALUMINA BASED METAL ORGANIC FRAMEWORK (MIL-53 Al)

Abstract

Metal organic frameworks are highly porous materials which are formed by combination of metal precursor and salts as inorganic part and ligand as organic part. They have many advantages such as low density, high surface area, tunable pore size and high porosity. Due to peculiar features, such as unsaturated metal active sites, high surface area and easily functionalization, its usage as catalyst are promising.

 

The MIL-53(Al) structure contains chains of trans corner-sharing [AlO₄(OH)₂] octahedra that are connected to each other by 1,4 benzenedicarboxylate (BDC) ligands, and thus 3D net in which one-dimensional channels run parallel to the inorganic backbone of the structure is formed. There are so many studied on usage of aluminium based metal organic framework in adsorption and gas adsorption and separation processes. However, there is very limited number of studies on catalytic properties of this material.

 

MIL-53(Al) provides several advantages compared with other MOFs such as high thermal stability, cheap, and available raw materials. It is also moisture resistant and has relatively high surface area which makes it an attractive MOF alternative for catalytic processes. In this study, aluminium salt was selected as metal precursor and MIL-53 (Al) was synthesized by solvothermal method.

 

Then the synthesized material was sulfated to increase the acidity. The characterization of synthesized and sulfated materials were performed by FT-IR, BET, XRD and TGA methods. The catalytic activity of sulfated material was tested in esterification reaction of acetic acid. The effects of time, sulfation, temperature and alcohol type were investigated. 

Keywords

• MOF,MIL-53(Al),solvothermal,sulfation,and acidity

References

1. Patil, D. V.; Rallapalli, P. B. S.; Dangi, G. P.; Tayade, R. J.; Somani, R. S.; Bajaj, H. C. Industrial and Engineering Chemistry Research 2011, 50 (18), 10516–10524. Zhou, M.; Wu, Y. N.; Qiao, J.; Zhang, J.; McDonald, A.; Li, G.; Li, F. Journal of Colloid and Interface Science 2013, 405, 157–163. Xie, L.; Liu, D.; Huang, H.; Yang, Q.; Zhong, C. Chemical Engineering Journal 2014, 246, 142–149. Trung, T. K.; Trens, P.; Tanchoux, N.; Bourrelly, S.; Llewellyn, P. L.; Loera-Serna, S. Journal of the American Chemical Society 2008, 53 (22), 78035. Hu, Y. H.; Zhang, L. Advanced Materials 2010, 22 (20), 1–14. Himsl, D.; Wallacher, D.; Hartmann, M. Angewandte Chemie - International Edition 2009, 48 (25), 4639–4642. Maes, M.; Vermoortele, F.; Alaerts, L.; Couck, S.; Kirschhock, C. E. a; Denayer, J. F. M.; De Vos, D. E. Journal of the American Chemical Society 2010, 132 (43), 15277–15285. Goesten, M. G.; Juan-Alcañiz, J.; Ramos-Fernandez, E. V.; Sai Sankar Gupta, K. B.; Stavitski, E.; Van Bekkum, H.; Gascon, J.; Kapteijn, F. Journal of Catalysis 2011, 281 (1), 177–187. Hassan, S. M.; Ibrahim, a a; Mannaa, M. a. 2013, 4 (2), 104–116. Qu, Y.; Peng, S.; Wang, S.; Zhang, Z.; Wang, J. Chinese Journal of Chemical Engineering 2009, 17 (5), 773–780. Sert, E.; Buluklu, A. D.; Karakuş, S.; Atalay, F. S. Chemical Engineering and Processing: Process Intensification 2013, 73, 23–28. Sert, E.; Atalay, F. S. Chemical Engineering and Processing: Process Intensification 2014, 81, 41–47.