Mesoporous and Macroporous Alumina-Supported Nickel Adsorbents for Adsorptive Desulphurization of Commercial Diesel

Abstract

High-performance X%NiO x /Al 2 O 3 adsorbents were prepared using mesoporous and macroporous alumina for adsorptive desulphurization (ADS) of commercial diesel (total sulphur content, 150 ppmw) at atmospheric pressure. Among the synthesized adsorbents, the reduced mesoporous and macroporous 20%NiO x /Al 2 O 3 (Re20%NiO x /Al 2 O 3 ) presented the breakthrough capacity of 1.47 mg-S/g-sorbent with sulphur level of 10 ppmw. The ultra-deep desulphurization properties for two adsorbents were evaluated using simulated fuels. The adsorbent with macropores showed a superior desulphurization performance, and the existence of macropores remarkably increased its breakthrough capacity as well as improved the space steric hindrance effect. The adsorbents synthesized were characterized by nitrogen adsorption isotherms (BET), X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, temperature-programmed reduction of hydrogen, temperature-programmed desorption of ammonia and Fourier transform infrared techniques. The results showed that the synthesized adsorbents were stable, contained acid sites, especially Lewis acid sites, which played an important role in ADS. Even after three cycles of regeneration, the organic sulphur-adsorption capacity of Re20%NiO x /Al 2 O 3 was more than 80%.