Hierarchical Porous Nitrogen-Doped Carbon Modified with Nickel Nanoparticles for Selective Ultradeep Desulfurization

We report herewith, a biomass derived carbon from groundnut shell (GN-AC) treated with melamine to achieve nitrogen-doped carbon (CN), followed by modification with nickel-precursor by solid-state impregnation to achieve reticulated nickel nanoparticles-modified nitrogen-doped carbon (Ni-CN) adsorbent. Incorporation of heteroatoms and the subsequent loading of nickel nanoparticles on the porous carbon exhibits fast and remarkable adsorption capacity for dibenzothiophene. The sulfur removal efficiencies of CN and Ni-CN are 40.49 and 44.77 mg-S/g-adsorbent, respectively, compared to 29.63 mg-S/g achieved for bare carbon in 500 ppmw-S. This excellent performance is attributed to synergy effect of nitrogen heteroatoms and nickel nanoparticles with improved surface chemistry and textural properties. The physical-chemical properties of the adsorbents were characterized by Boehm titration, N₂-physisorption, FTIR, XRD, XPS, Raman, SEM and TEM. The kinetics and isotherms investigation of the adsorbents data fitted pseudo-first order and Langmuir models, respectively. The Ni-CN adsorbent also displays an excellent selectivity and regeneration potential for commercial viability.