Ah Rim Jeong

Adsorptive removal of indole and quinoline from model fuel using adenine-grafted metal-organic frameworks

A highly porous metal-organic framework (MOF), MIL-101, was modified for the first time with the nucleobase adenine (Ade) by grafting onto the MOF. The Ade-grafted MOF, Ade-MIL-101, was further protonated to obtain P-Ade-MIL-101, and these MOFs were utilized to remove nitrogen-containing compounds (NCCs) (such as indole (IND) and quinoline (QUI)) from a model fuel by adsorption. These functionalized MOFs exhibited remarkable adsorption performance for NCCs compared with that shown by commercial activated carbon (AC) and pristine MIL-101, even though the porosities of the functionalized-MOFs were lower than that of pristine MIL-101. P-Ade-MIL-101 has 12.0 and 10.8 times capacity to that of AC for IND and QUI adsorption, respectively; its adsorption performance was competitive with that of other reported adsorbents. The remarkable adsorption of IND and QUI by Ade-MIL-101 was attributed to H-bonding. H-bonding combined with cation-π interactions was proposed as the mechanism for the removal of IND by P-Ade-MIL-101, whereas acid-base interactions were thought to be responsible for QUI adsorption by P-Ade-MIL-101. Moreover, P-Ade-MIL-101 can be regenerated without any severe degradation and used for successive adsorptions. Therefore, P-Ade-MIL-101 was recommended as an effective adsorbent for fuel purification by adsorptive removal of NCCs.

Synthesis, structure, and magnetic properties of dicopper and tricobalt complexes based on N-(2-pyridylmethyl)iminodiethanol

Dinuclear [Cu(H2pmide)(NO3)Cu(Hpmide)](NO3)2 (1) and trinuclear [(pmide)2Co3(CH3CO2)2(NCS)2]·4CH3OH (2) coordination complexes have been prepared by the reaction of the tetradentate H2pmide ligand and Cu(NO3)2·3H2O or Co(CH3CO2)2·4H2O/NaNCS in organic solvent (H2pmide = N-(2-pyridylmethyl)iminodiethanol). In 1, one copper(II) ion is bonded with a H2pmide, and the other is coordinated with a mono-deprotonated Hpmide−. The copper(II) ions are linked through an ethoxo group of the Hpmide− ligand and two oxygen atoms of a nitrate ion, resulting in an asymmetric dinuclear structure. In 2, two terminal cobalt(III) units are coordinated with pmide2−, NCS−, and CH3CO2−. The terminal units are each connected to a central cobalt(II) cation through the two oxygen atoms of pmide2− and one bridged acetate ion, giving rise to a mixed-valence trinuclear cobalt complex formulated as CoIII–CoII–CoIII. Complex 1 shows a strong antiferromagnetic interaction through the ethoxo and nitrato groups between the copper(II) ions [g = 2.070, J = –88.1 cm−1 (–61.2 K)]. However, complex 2 behaves as a paramagnetic cobalt(II) monomer, due to the diamagnetic cobalt(III) ions in the terminal units [g = 2.526, |D| = 51.8 cm−1 (36.0 K)].