Magnetization and Mössbauer spectroscopic study of adsorption oxalic acid on α-Fe2O3 from solutions

✍ Scribed by Nai Fu Zhou; Long-Wu Chen; Yin-Sheng Wang; Ji-Sen Jiang

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 614 KB
• Volume: 224
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(94)00594-x

✦ Synopsis

The adsorption of oxalic acid on (]-Fe203 (hematite) from solutions was studied by magnetization and M6ssbauer spectroscopic measurements. The adsorption showed a Langmnir isotherm and strong dependence on the solution pH. However, the magnetization and the surface M6ssbauer parameters of hematite after adsorption of oxalic acid were affected by the temperature rather than the solution pH. Two types of interactive force were identified, i.e. physical adsorption and the surface chemical reaction with the formation of ferric oxalate. A 'spin pinning' magnetic model was proposed for explaining the depression of magnetization for the surface species.