Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 21st October 2020 from 07:00 AM to 07:00 PM (BST).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.

Issue 17, 2002
Previous Article Next Article

Acid–base properties of Cu1−xCoxFe2O4 ferrospinels: FTIR investigations

Author affiliations


Systematic IR spectroscopic studies were undertaken to investigate the acid–base properties of Cu–Co ferrospinels Cu1−xCoxFe2O4 (x = 0 to 1) employed in phenol methylation to produce 2,6-xylenol. The IR spectra of the ferrospinels reveal that Fe3+ and Co2+ ions are mainly responsible for the various hydroxy groups on the surface. Temperature dependent IR studies of pyridine adsorbed on spinels and on the spinel phase with deliberately added metal oxide exemplify the contribution of the metal ions and their coordination state towards Lewis acidity. IR studies of the spinel surface with adsorbed CO2 and adsorption studies of electron acceptors such as 7,7,8,8-tetracyanoquinodimethane, 2,3,5,6-tetrachloro-1-4-benzoquinone and p-dinitrobenzene were carried out to evaluate the nature of the basic sites and the strength and distribution of the electron donor sites present on the spinel surface. It was found that the acidity (basicity) of the Cu1−xCoxFe2O4 spinel system increases (decreases) from x = 0 to 1. A correlation between acidity, basicity and catalytic performance reveals that an intermediate acid–base character enhances the phenol methylation activity.

Back to tab navigation

Article information

02 May 2002
24 Jun 2002
First published
19 Aug 2002

Phys. Chem. Chem. Phys., 2002,4, 4260-4267
Article type

Acid–base properties of Cu1−xCoxFe2O4 ferrospinels: FTIR investigations

T. Mathew, B. B. Tope, N. R. Shiju, S. G. Hegde, B. S. Rao and C. S. Gopinath, Phys. Chem. Chem. Phys., 2002, 4, 4260
DOI: 10.1039/B204226F

Social activity

Search articles by author