title: Effective adsorptive removal of indole from model fuel using a metal-organic framework functionalized with amino groups.
abstract: Nitrogen-containing compounds (NCCs) should be removed from fuels because of the negative effect of NCCs on the environment and catalyst stability. NCCs are composed of basic materials such as quinoline (QUI) and neutral materials such as indole (IND). The NCCs can be removed by various methods including adsorption. Compared with basic NCCs, neutral NCCs are more difficult to remove through adsorption due to their less affinity toward adsorbents. In this report, adsorption of IND (as one of the representative neutral NCCs) was studied over the metal-organic frameworks (MOFs), UiO-66 and UiO-66-NH2, which contain terephthalate and aminoterephthalate linkers, respectively. In spite of the reduced porosity of UiO-66-NH2, the adsorption capacity of IND was improved upto 46% when compared with pristine UiO-66. Therefore, the additional amino group in the MOF imparts extra adsorption capability on the MOF. For a detailed investigation, adsorption of other NCCs such as QUI, pyrrole, and methylpyrrole was studied. The improved adsorption of IND over amino-functionalized MOFs could be attributed to the improved interaction of IND with the MOF via H-bonding because of the NH2 group. In addition to this remarkable improvement in IND adsorption, UiO-66-NH2 could be regenerated several times for the adsorption of IND by simple solvent washing.
authors.affiliation: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea.
authors.forename: Imteaz
authors.initials: I
authors.lastname: Ahmed
authors.affiliation: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea. Electronic address: sung@knu.ac.kr.
authors.forename: Sung Hwa
authors.initials: SH
authors.lastname: Jhung
mesh_terms: D000327:Adsorption; D005579:Fossil Fuels; D007211:Indoles / Q000737:chemistry*; D017672:Nitrogen Compounds / Q000737:chemistry*
chemical_list: D005579:Fossil Fuels; D007211:Indoles; D017672:Nitrogen Compounds; C030374:indole
keywords: Amino group; Hydrogen-bond; Indole adsorption; Metal-organic frameworks; UiO-66