Inorganic-organic hybrid sorbent for aromatic desulfurization of hydrocarbons: Regenerative adsorption based on a charge-transfer complex
Document Type
Article
Publication Date
1-1-2016
Abstract
A new series of inorganic-organic hybrid materials as sorbents for the adsorption of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) have been prepared by functionalizing mesoporous silica with 9,10-anthraquinone derivatives. A selected sorbent was fully characterized via13C and 29Si cross-polarization magic-angle solid-state nuclear magnetic resonance (CP-MAS NMR), FTIR spectroscopy, powder X-ray diffraction (PXRD) and thermal analysis (TGA-DTA). The prepared materials were used to adsorb DBT and 4,6-DMDBT from C7 hydrocarbons under ambient conditions. The results show that the hybrid material prepared by the functionalization of mesoporous silica with 9,10-dioxo-5-((3-(triethoxysilyl)-propyl)amino)-1,5-dichloro-4,8-dinitroanthraquinone is an efficient and regenerable sorbent for adsorption of DBT and 4,6-DMDBT by π-π interaction. To demonstrate the adsorption of DBT and 4,6-DMDBT through π-π interaction, a charge-transfer complex (CTC) of 1,5-dichloro-4,8-dinitroanthraquinone and 4,6-DMDBT was prepared and characterized by FT-IR, 1H and 13C NMR spectroscopy, MS, TGA-DTA and single-crystal X-ray diffraction. The results show that 1,5-dichloro-4,8-dinitroanthraquinone produces a CTC with 4,6-DMDBT, and when it is grafted on Si-MCM-41, it produces a hybrid material with the capability of adsorbing only aromatic DBT and 4,6-DMDBT rather than anthracene, naphthalene and xylene. In contrast, 1,5-dichloroanthraquinone and 1,5-dicyanoanthraquinone neither produce a CTC nor adsorb DBT, 4,6-DMDBT, anthracene, naphthalene and xylene after they are grafted on Si-MCM-41. This study proves that the hybrid material prepared from mesoporous silica and 9,10-dioxo-5-((3-(triethoxysilyl)-propyl)amino)-1,5-dichloro-4,8-dinitroanthraquinone is an efficient, environmentally benign and regenerable sorbent for the removal of DBT and 4,6-DMDBT from C7 hydrocarbons.
Keywords
Adsorption, Anthracene, Aromatic compounds, Aromatic hydrocarbons, Charge transfer, Fourier transform infrared spectroscopy, Grafting (chemical), Hydrocarbons, Mesoporous materials, Naphthalene, Nuclear magnetic resonance spectroscopy, Silica, Single crystals, Sorbents, Sorption, Thermoanalysis, X ray diffraction, Xylene
Divisions
Science
Publication Title
RSC Advances
Volume
6
Issue
88
Publisher
Royal Society of Chemistry