Aim and Objective: The research focuses on recent progress in the production of light
olefins. Hence, as the common catalyst of the reaction (SAPO-34) deactivates quickly because of
coke formation, we reorganized the mechanism combining SAPO-34 with a natural zeolite in order
to delay the deactivation time.
Materials and Methods: The synthesis of nanocomposite catalyst was conducted hydrothermally
using experimental design. Firstly, Clinoptilolite was modified using nitric acid in order to achieve
nano-scaled material. Then, the initial gel of the SAPO-34 was prepared using DEA, aluminum
isopropoxide, phosphoric acid and TEOS as the organic template, sources of Aluminum, Phosphor,
and Silicate, respectively. Finally, the modified zeolite was combined with SAPO-34's gel.
Results: 20 different catalysts due to D-Optimal design were synthesized and the nanocomposite
with 50 weight percent of SAPO-34, 4 hours Crystallization and early Clinoptilolite precipitation
showed the highest relative crystallinity, partly high BET surface area and hierarchical structure.
Conclusion: Different analyses illustrated the existence of both components. The most important
property alteration of nanocomposite was the increment of pore mean diameters and reduction in
pore volumes in comparison with free SAPO-34. Due to the low price of Clinoptilolite, the new
catalyst renders the process as economical. Using this composite, according to the formation of
multi-sized pores located hierarchically on the surface of the catalyst and increased surface area,
significant amounts of Ethylene and Propylene, in comparison with free SAPO-34, were produced,
as well as the deactivation time was improved.