The effect of calcium ions on the adsorption of phosphonic acid: a comparative investigation with emphasis on surface analytical methods

✍ Scribed by E. Kálmán; F.H. Kármán; I. Cserny; L. Kövér; J. Telegdi; D. Varga

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 403 KB
• Volume: 39
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(94)e0034-w

✦ Synopsis

The mllueme of calcmm ions on the adsorption of 1-hydroxy-ethane-1,ldlphosphomc acid (HEDP) on Fe electrodes has been examined Surface analytical methods (XPS and XAES) have been applied m order to obtam direct mformatlon on the structure of the surface layer On the surfaces of electropohshed samples, vanous Fez+, Fe3+ and FeOOH compounds as well as the metalhc state of Fe could be ldentdied m the surface layers HEDP was adsorbed on the iron surface in almost the same extent, when the basic solutions were bldlstdled water or 0 5mol dme3 NaCIO,, respecttvely The presence of Ca2 + cations increased the quantity of phosphonate adsorbed on the metal surface considerably Varymg the Ca/HEDP molar ratio m the solution between 0 5 and 4 0, the Ca/HEDP molar ratio on the metal surface remained under a llrmt close to one, correspondmg to what could be expected on the basis of the results obtained by radiotracer method