Efficient Adsorptive Denitrogenation of Liquid Fuel with Polyaniline-Derived Porous Carbons

Highly porous polyaniline-derived carbons (pDCs) were used as adsorbents to adsorb/remove hazardous organonitrogens (ONs) from liquid fuel for the first time. The nitrogen-rich pDCs were obtained via the carbonization of polyaniline (pANI) under an inert atmosphere. Further, the pDCs were activated in the presence of KOH (as a chemical activating agent) at different pyrolysis temperatures (600 to 800 oC) to increase the porosity or surface area of the pDC. One pDC prepared at 700 oC (named pDC-b) showed very efficient adsorptions of representative ONs (indole and quinoline) from liquid fuel. The pDC-b had a maximum adsorption capacity of 458 mg/g of quinoline which is the highest among the reported values with carbon-based adsorbents. The maximum adsorption capacity of the same adsorbent for the adsorption of indole (385 mg/g) was also very competitive against other carbonaceous adsorbents. The high adsorption capacities of the pDC-b could be interpreted by a synergistic effect of an efficient hydrogen bonding (between the heteroatoms of pDC-b and the adsorbates) and high porosity of the adsorbent (SABET> 2000 m2/g). In addition, a simple solvent washing could regenerate the pDC-b for the successive utilization in adsorptions effectively