Interfacial behaviour of LIX 63 and The Surface Kinetics of Copper Extraction

✍ Scribed by K. Prochaska; Prof. Dr. J. Szymanowski; K. Alejski; M. A. Hughes

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 736 KB
• Volume: 332
• Category: Article
• ISSN: 1615-4150
• DOI: 10.1002/prac.19903320302

✦ Synopsis

Abstract

Different adsorption isotherms such as the Szyszkowski, Temkin, Frumkin, polynomial and spline functions were explore as fits to the experimental interfacial tension isotherms for LIX‐63‐hexane/water and LIX‐63‐toluene/water systems and then the surface excess isotherms were computed. A good match was obtained. The surface excess isotherms change in a similar way as those reported previously for 2‐hydroxy‐5‐alkylbenzophenone oximes.

Kinetic equations were derived for various versions of the extraction mechanism at the molecular interface, and the interfacial tension data were then used to estimate reaction orders against hydroxyoxime concentrations assuming that the process occurs at the interface of molecular dimensions. A reaction order equal one was obtained in the case of the formation of the stable 2:1 complex from the surface adsorbed intermediate 1:1 complex with a hydroxyoxime molecule held in the aqueous sublayer. This is the slowest step in the overall process. Hydroxyoxime association has only a small effect upon the predicted reaction orders and can be neglected.