Effect of H{sub 3}PW{sub 12}O{sub 40} impregnation on Sn-MCM-41 mesoporous molecular sieves and their physico-chemical properties

Journal Article · Thu Jan 15 04:00:00 EST 2015 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2014.09.080· OSTI ID:22420734

Nedumaran, D. ^[1]

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1. Department of Chemistry, Institute of Catalysis and Petroleum Technology, Anna University, Chennai 600025 (India)

Graphical abstract: The wide angle XRD shows the well dispersion of HPWA in Sn-MCM-41. It enhances the total acidity of the material. The acidity of the material is correlated with sulfone selectivity. The FT-IR of dibenzothiophene and product shows the formation of sulfone (DBTO{sub 2}). - Highlights: • To enhance the total acidity of Sn-MCM-41 TPA is impregnated. • FT-IR and {sup 31}P MAS NMR confirms the HPWA intact on Sn-MCM-41. • EDAX shows the presence of W and P on Sn-MCM-41. • In ODS formation of sulfone was confirmed by FT-IR and {sup 1}H NMR. • The order of the catalytic activity of the catalysts are 18HSnM > 28HSnM > 8HSnM. - Abstract: Si-Sn-MCM-41 (Si/Sn = 110) mesoporous molecular sieve was synthesized by hydrothermal sol–gel method using cetyltrimethylammonium bromide (CTAB) as surfactant and SnCl{sub 4}·5H{sub 2}O as a metal source. To generate surface acidity of Si-Sn-MCM-41, 12-tungstophosphoric acid (HPWA) is impregnated on it. The acidity of HPWA loading on Sn-MCM-41 was investigated by temperature programmed desorption of NH{sub 3}. The diffused reflectance spectra of ultraviolet radiation, Raman spectra, FT-IR, {sup 29}Si-MAS NMR and {sup 31}P-MAS NMR techniques revealed the intact of α-Keggin anions on Sn-MCM-41. The wide angle XRD results showed that the HPWA is well dispersed on the support. The total acidity was enhanced with increase in loading of H{sub 3}PW{sub 12}O{sub 40}. The catalytic activity was examined in desulfurization of dibenzothiophene in vapor phase system. Among the catalysts 18% HPWA loaded Sn-MCM-41 showed good catalytic activity in desulfurization at 325 °C. The HPWA/Sn-MCM-41 are a suitable solid acid catalyst for converting organic sulfur into insoluble sulfone.

• OSTI ID: 22420734
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Vol. 61; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHEMICAL PROPERTIES
DESORPTION
DESULFURIZATION
FOURIER TRANSFORMATION
HYDROGEN 1
INFRARED SPECTRA
MOLECULAR SIEVES
NANOSTRUCTURES
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
PHOSPHORUS 31
RAMAN SPECTRA
RAMAN SPECTROSCOPY
SILICON 29
SURFACE PROPERTIES
TIN CHLORIDES
TUNGSTOPHOSPHORIC ACID
ULTRAVIOLET RADIATION
X-RAY DIFFRACTION