Remarkable improvement in adsorptive denitrogenation of model fossil fuels with CuCl/activated carbon, prepared under ambient condition

CuCl-loaded activated carbons (ACs) have been used for the first time to remove harmful nitrogen-containing compounds (NCCs) from model fossil fuels. The CuCl/ACs were obtained by reducing CuCl₂/ACs with Na₂SO₃ under ambient conditions. A mixture of quinoline (QUI), indole (IND) and benzothiophene (BT) was used to investigate the adsorption behaviors. QUI and IND were used to represent basic and neutral NCCs, respectively. On the other hand, BT is a sulfur-containing compound (SCC) that was used to mimic commercial fuels and investigate the selectivity of adsorption for NCCs over SCCs. The adsorption capacities of CuCl/AC for QUI and IND increased by almost 100% from that of pristine AC, even though the surface area of the CuCl/AC was lower than that of the AC. On the contrary, the adsorbed amounts over CuCl₂/AC (loaded without using Na₂SO₃) for QUI and IND were slightly lower than the adsorbed amounts over the virgin AC. The improved adsorptive performances of CuCl/AC for NCCs might be due to π-complexation between Cu⁺ species and NCCs.