Aromatization of LPG over ZnO/ZSM-5 Catalysts: Statistical Optimization of Process Variables
Authors: Isa AR, Gbadamasi S, Fasanya OO, Ahmed UO, Gano ZS, Atta AY, Mukhtar B, Aderemi BO, Jibril BY
Research efforts are being made regarding one-step production of petrochemical feedstocks from natural gas, liquefied petroleum gas (LPG) and natural gas liquids (NGLs) which will guarantee the continuous supply of hydrocarbon chemical feedstocks. In this regard, a statistical approach for optimizing the process variables (reaction temperature, catalyst weight and zinc oxide (ZnO) wt% loading on ZSM-5) in LPG aromatization over ZnO/ZSM-5 catalyst was carried out in this work. Three different ZnO loaded ZSM-5 (Si/Al=50) catalysts were prepared and characterized by N2 adsorption-desorption, XRD, UV-Vis, SEM, and IR spectra of pyridine adsorption. D-optima experimental design was used to establish the interaction effects of the variables towards LPG conversion and aromatic selectivity while response surface methodology (RSM) was employed in optimizing the experimental process variables in the aromatization process. A second order regression model was developed and the coefficient of determination (R2) was determined to be 95.61%. Optimum LPG conversion of 94.75% was achieved at 520 °C for 0.245 g catalyst weight and 5 wt% ZnO loading with a corresponding aromatic selectivity of 22.38%.
Affiliations: Department of Chemical Engineering, Ahmadu Bello University, Zaria, Nigeria.
Keywords: LPG, Aromatization, Aromatics, ZnO, ZSM-5, RSM
Published date: 2019/06/30