Adsorptive desulfurization and denitrogenation by nickel impregnated activated carbon

Abstract

Nickel impregnated granular activated carbon (Ni-GAC) has been synthesized and characterized by various techniques like BET, FTIR, SEM, EDX and TGA. It is later employed for the individual adsorption of dibenzothiophene (DBT) and quinoline (QN). The influence of various factors such as percentage of Ni loading, initial concentration, time, adsorbent dose and temperature on the individual adsorption of DBT and QN from model fuel by Ni-GAC have been investigated. On the basis of the present study, 1%Ni-GAC is found to be the best among various wt.% Ni-GAC. Equilibrium time for DBT and QN adsorption is found to be 6 hr and 9 hr, respectively. The optimum adsorbent dose is found to be 20 g/L. Adsorption kinetics of the both DBT and QN are represented by pseudo-second-order kinetic model. For single component systems, the experimental equilibrium data is well matched with R-P isotherm. Values of change in enthalpy and entropy for DBT and QN were found to be 2.04, 1.55 kJ/mol and 10 and 20 J/mol K, respectively. Isosteric heat of adsorption is modeled in terms of surface heterogeneity.