Desulfurization studies of liquid fuels through nickel-modified porous materials from Pongamia pinnata

Abstract

A new biomass-based carbonaceous adsorbent has been developed from Pongamia pinnata and its effect upon nickel modification- and adsorption-coupled ultrasonication was investigated. Adsorption experiment of the model oil constituting 50 ppm dibenzothiophene in cyclohexane showed the maximum capacity as 8.11, 13.36, and 17.15 mg·g−1 for the commercial carbon DARCO, virgin bio-adsorbent PP, and nickel-modified adsorbent Ni@PP, respectively, with the time required for attaining equilibrium being the fastest in Ni@PP (120 min). The significant effect of ultrasonication was in attaining faster kinetics where ~ 96–98% removal was achieved in only 30 min. Also, the developed adsorbents had a very good specific surface area of 915 and 677 m2·g−1, respectively, for PP and Ni@PP. Investigation of the effect of higher initial sulfur concentration (200 ppm) indicated the significance of Ni modification, where a very high capacity of 66.18 mg·g−1 for Ni@PP was attained against 30.90 mg·g−1 for PP and 13.18 mg·g−1 for DARCO. Ni@ PP was also effective for the simultaneous removal of more refractory sulfur fractions from multicomponent model fuel systems and exhibited good regeneration ability till the fourth cycles or more. Cost estimation showed that the developed adsorbents are relatively ten times cheaper than commercial carbon, while the fixed-bed study indicated a breakthrough time of 250 min and 270 min for PP and Ni@PP, respectively. Graphic abstract

Green Synthesis of Ni/Fe3O4/rGO Nanocomposites for Desulfurization of Fuel

“…In order to define the plausible mechanism for adsorptive desulfurization, all the possible interactions between substrate and adsorbent material and the active centers were identified and investigated properly. A number of interactions such as van der Waals, hydrogen bonding, π–π interaction,and electrostatic attraction are responsible for the adsorption process . In the case of nonmodified carbon nanostructured materials like graphene oxide, acidic (−COOH) and hydroxyl (−OH) groups present on the surface are responsible for the possible acid–base interaction with the S-compound .…”

“…A number of interactions such as van der Waals, hydrogen bonding, π−π interaction,and electrostatic attraction are responsible for the adsorption process. 67 In the case of nonmodified carbon nanostructured materials like graphene oxide, acidic (−COOH) and hydroxyl (−OH) groups present on the surface are responsible for the possible acid−base interaction with the S-compound. 68 Additionally, there is a π−π interaction between conjugated π-bonds of the two benzene rings of DBT and graphene oxide, which is also responsible for desulfurization.…”

Sequential Approach to Liquid Fuel Desulfurization through Rhodococcus erythropolis Assisted Molybdenum Modified Euryale ferox Biomass

“…The FAT synthesis procedure was followed by a slightly modified version of our previously reported carbonization method Euryale ferox shells were obtained locally near Delhi (India), washed adequately with tap water to remove all impurities, and sun-dried for 12 h. The dried pods were crushed into a fine powder and sieved through a 60/ASTM-30 sieve (aperture width: 0.592 mm).…”

“…The FAT synthesis procedure was followed by a slightly modified version of our previously reported carbonization method. 35 impurities, and sun-dried for 12 h. The dried pods were crushed into a fine powder and sieved through a 60/ASTM-30 sieve (aperture width: 0.592 mm). The sieved powder was then treated with H 3 PO 4 (1:1; w/ v) at 60 °C for 1 h and then heated to 500 °C for 1 h at a rate of 10 °C per min in a muffle furnace.…”

“…As a result, their residue is employed as a starting material for the production of activated carbon (FAT). Activated carbon has a number of exposed surface groups, such as hydroxyl, carboxyl, amines, etc., that act as binding sites for incoming highly electropositive metal ions via electrostatic, dipole–dipole, and coordinate covalent bonding . Mo in its highest positive oxidation state Mo 6+ , provides unoccupied d- and s-orbitals for interaction with thiophenic compounds during the desulfurization process.…”