Ni as the promoter on hydrogen spillover for better hydrogenative regeneration on Pt/Y based catalysts

For (Ni-Pt)/YA catalyst, the apparent active energy is approximately equal to that of hydrogen spillover (11.9 kal/mol), which is almost 30% lower than that of Pt/YA (17.3 kal/mol). [Display omitted] •H2 activation was divided into H2 dissociation and hydrogen spillover.•Ni increased the capability of H2 activation over (Ni-Pt)/YA experimentally.•Ni was selected as the promoter on hydrogen spillover theoretically.•With much less Pt, (5Ni-0.1Pt)/YA could completely be regenerated over 10 circles. Hydrogenative regeneration of Pt/YA catalysts is vital to continuous operation of solid acid isobutane/butene alkylation. From the view of H2 activation, the mechanism of hydrogenative regeneration was investigated experimentally and theoretically. Herein with Pt/YA as reference, (Ni-Pt)/YA catalysts were prepared with almost identical cell parameter and different Ni/Pt contents by wet impregnation method following by several characterization methods, such as XPS, H2-TPR, H2-TPD, STEM-CS and Elemental mapping. Strong interactions between Ni and Pt were proven by XPS and H2-TPR. Moreover Ni can increase the capability of hydrogen spillover, which could be observed by H2-TPD, with the higher desorption temperature and more desorbed H2. DFT calculations revealed that hydrogen spillover is the rate determining step for the overall H2 activation over Pt/YA, and Ni as the hydrogen spillover promoter could couple with Pt to enhance the overall H2 activation because of almost 30% lower energy barrier for hydrogen spillover. With rather low Pt content, no obvious loss in lifetime in the 10 cycles of reaction-regeneration was observed over (5Ni-0.1Pt)/YA with rather stable product distribution.