A mesoporous carbon (CMC) has been treated under acidic conditions (32.5 wt.% HNO3 at 10°C or 40°C) to prepare two new carbon samples (HCMC10 and HCMC40), which developed higher acidity in terms of quantity of sites and surface acid strength. The properties of the three carbons have been studied with various techniques (N2 adsorption/desorption, TEM, XRPD, Raman spectroscopy, 13C NMR, 2D 1H-13C NMR, and XPS). Aromatic COOH and OH groups were identified as the main surface acid sites. Acid site density has been determined by pulse liquid-solid phase adsorption experiments carried out in different liquids. The samples retained acidity features in water, due to hydrophobicity of the surfaces, while acidity dropped when measured in methanol. From NH3-TPD analysis, a ranking of acid strength could be obtained: HCMC40 > HCMC10 > CMC. The good acidity of the carbon samples allowed them to act as catalysts in the hydrolysis reaction of sucrose to glucose and fructose. The catalytic activity of the carbon samples was compared to that of Amberlite, a commercial sulfated acid resin; the observed kinetic constant of HCMC40 was similar to that of Amberlite.
Tunable acidity in mesoporous carbons for hydrolysis reactions / M. Ferri, S. Campisi, P.I. Carniti, A. Gervasini, J. Shen. - In: NEW JOURNAL OF CHEMISTRY. - ISSN 1144-0546. - 44:15(2020 Apr 21), pp. 5873-5883. [10.1039/D0NJ00750A]
Tunable acidity in mesoporous carbons for hydrolysis reactions
M. Ferri;S. Campisi;A. Gervasini
;
2020
Abstract
A mesoporous carbon (CMC) has been treated under acidic conditions (32.5 wt.% HNO3 at 10°C or 40°C) to prepare two new carbon samples (HCMC10 and HCMC40), which developed higher acidity in terms of quantity of sites and surface acid strength. The properties of the three carbons have been studied with various techniques (N2 adsorption/desorption, TEM, XRPD, Raman spectroscopy, 13C NMR, 2D 1H-13C NMR, and XPS). Aromatic COOH and OH groups were identified as the main surface acid sites. Acid site density has been determined by pulse liquid-solid phase adsorption experiments carried out in different liquids. The samples retained acidity features in water, due to hydrophobicity of the surfaces, while acidity dropped when measured in methanol. From NH3-TPD analysis, a ranking of acid strength could be obtained: HCMC40 > HCMC10 > CMC. The good acidity of the carbon samples allowed them to act as catalysts in the hydrolysis reaction of sucrose to glucose and fructose. The catalytic activity of the carbon samples was compared to that of Amberlite, a commercial sulfated acid resin; the observed kinetic constant of HCMC40 was similar to that of Amberlite.File | Dimensione | Formato | |
---|---|---|---|
NJC_CMC_10-02-2020.pdf
accesso aperto
Tipologia:
Pre-print (manoscritto inviato all'editore)
Dimensione
910.03 kB
Formato
Adobe PDF
|
910.03 kB | Adobe PDF | Visualizza/Apri |
d0nj00750a.pdf
accesso riservato
Tipologia:
Publisher's version/PDF
Dimensione
5.01 MB
Formato
Adobe PDF
|
5.01 MB | Adobe PDF | Visualizza/Apri Richiedi una copia |
Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.