MMT-supported Ni/TiO2 nanocomposite for low temperature ethanol steam reforming toward hydrogen production

Ni/TiO2 nanoparticles dispersed on montmorillonite (MMT) clay with different sizes for selective ethanol steam reforming with regard to hydrogen production has been investigated. Ni/MMT-TiO2 nanocomposite catalysts were prepared by a sol-gel assisted impregnation method. The samples were extensively characterized by X-ray diffraction (XRD), N-2 adsorption-desorption, Fourier transfer infrared (FTIR) spectroscopy, scanning electron coupled with energy dispersive X-ray (SEM-EDX) spectroscopy and thermogravimetric analysis (TGA). While Ni content progressively promoted the activity of TiO2 toward ethanol conversion and H-2 yield, modification with MMT controlled the crystal growth and produced anatase phase of delaminated MMT/TiO2 nanocomposite. Formation of a surface Ni-MMT phase in the modified Ni/MMT-TiO2 nanocomposite catalyst enhanced Ni-dispersion and reducibility. Various parameters concerning the effect of temperature, steam-to-ethanol (S/E) feed ratio, MMT loading and Ni-metal loading on the catalytic performance, were thoroughly studied. The optimal performance was achieved for 12 wt. % Ni/20 wt. % MMT-TiO2, achieving an ethanol conversion of 89% and a H-2 yield of up to 55% at 500 degrees C. In addition, the Ni/MMT-TiO2 nano-composite catalyst possessed the excellent stability at the optimum temperature, over 20 h reaction time. The relative low cost, good activity and stability of MMT modified Ni/TiO2 catalyst offers for an economical and feasible route for production of renewable hydrogen from ethanol. (C) 2017 Elsevier B.V. All rights reserved.