Aleksei Bolshakov

Research Project Emiel Hensen Aleksei Bolshakov

Design and synthesis of nanostructured zeolites for MTO reaction

Background

Aluminium-containing zeolites are widely used as porous acid catalysts in petrochemical and oil refining industry. Zeolite micropores, usually induced upon condensation by small organic molecules that act as structure-directing agents (SDAs) provide the possibility of shape-selective catalysis. Unfortunately, small pores also inhibit molecular transport within zeolite crystals, resulting in lower reaction rates and/or undesired side-reactions such as coking. To overcome this, the development of zeolites containing a secondary, mesoscale pore network has been widely explored. Such hierarchical zeolites – referring to the hierarchical arrangement of two types of pore size – naturally possess improved molecular transport, whilst retaining shape-selectivity in catalysis.

However, an ability to tailor the zeolite micro- and mesostructured to make it benign for specific applications requires control over nucleation and particle growth processes. Yet, the nucleation and crystallization mechanisms of zeolites are not fully understood [1].

In this work we will investigate the fundamental mechanism of formation ZSM-5 zeolite by using in-situ methods, such as Raman spectroscopy, NMR, Small angle X-ray scattering (SAXS), Small-angle neutron scattering  (SANS) and  also cryoTEM. The synthesis of an all-silica zeolite with MFI-type framework has been studied extensively as a model system [1,2]. So next step is to examine a silica-alumina system, which widely used as catalyst in methanol to olefins (MTO) and methanol to hydrocarbons (MTH) reactions.

Another aim of this project is to consider the formation of zeolites (MFI, MEL, CHA framework types) using quaternary ammonium salts as templates and, apply this knowledge on creating mesoporous structure in zeolites.  We would like to use the new breakthrough stochastic optical reconstruction microscopy (STORM) method (fluorescence microscopy), for detailed analyze of mesopores. The zeolites will be tested MTO reaction.

Techniques used:

XRD, FTIR spectroscopy, ICP, liquid and solid NMR, N2 physisorption, TEM, SEM

For further information:

Emiel Hensen (Helix, STW 3.35), Tel 5178,  e.j.m.hensen@tue.nl Aleksei Bolshakov (Helix, STW 3.29), Tel 2426, A.Bolshakov@tue.nl 

 

[1] Kumar, S.; Wang, Z.; Penn, R. L.; Tsapatsis, M. J. Am. Chem. Soc. 2008, 130, 17284.

[2] Möller, K.; Bein, T., ''' Mesoporosity – a new dimension for zeolites' Chem. Soc. Rev. 2013, 42, 3689