Effect of different precursor species on the metal dispersion of a Ni/γ-Al2O3 adsorbent for sulfur adsorption

Nickel adsorbents supported on the gamma-Al2O3 with different nickel precursor species were prepared by the incipient impregnation method to investigate the influence of different precursor species on the metal dispersion and the sulfur capacity of the adsorbents. The adsorbents were characterized by N-2 adsorption-desorption, H-2 temperature-programmed reduction (TPR), transmission electron microscopy (TEM), O-2-H-2 chemisorption, and FT-IR of adsorbed pyridine. The sulfur adsorption performance was investigated at ambient temperature and pressure. The results showed that adsorbent's metal dispersion and sulfur capacity were influenced significantly by the metal precursor species. The adsorbents prepared by nickel nitrate exhibited higher sulfur capacity and metal dispersion compared to the adsorbents prepared by nickel formate and nickel acetate. The higher performance of adsorbent prepared by nickel nitrate can be mainly attributed to the relatively more uniform metal dispersion and the smaller particle size of the nickel particles. This study demonstrates that the precursor species is an important factor for affecting the adsorption performance and provides a novel design idea of high metal dispersed catalysts.