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The transformation of 2-methylthiophene (100 ppm) in an n-hexane stream was studied on clays with nature/quantity of distinct acid sites aiming at evaluating the opening of thiophenic ring and the formation of H2S to be used in the desulfurization of fuels. KSF clay was modified with the impregnation of zinc (Zn/KSF), and the introduction of aluminum oxide pillars (KSF-PILC and Zn/KSF-PILC). The prepared materials were characterized using XRD, N2 physisorption, XRF, DRIFTS-C5H5N, TPD-NH3, SEM, and TPO. It was observed that the introduction of pillars decreased the Bronsted/Lewis ratio, and increased the total strength of acid sites. The catalytic evaluation showed that hydrogen transfer reactions can lead to the formation of H2S or 2-propanethiol (opening of the thiophenic ring). It was verified that the KSF clay possesses a higher Bronsted acid site count, leading, predominantly, to the formation of H2S. The addition of zinc to the pillarized clay (Zn/KSF-PILC) increased the quantity of Lewis acid sites, and decreased hydrogen transfer, having as the main product 2-propanethiol, resultant of the opening of the thiophenic ring. Pillarization also resulted in a lower formation of coke on the catalyst. |
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