Hydroxamic Acids as Chelating Mineral Collectors

Abstract

Owing to the ability to form coordination complexes with several metal ions, hydroxamic acids have application in different fields such as analytical chemistry, chelation therapy, nuclear fuel reprocessing, solvent extraction, ion exchange and mineral processing. Application of hydroxamic acids as chelating mineral collectors for ore beneficiation is a unique area of their use and has attracted the attention of limited readers working in the relevant area. A review of the use of alkyl and aryl hydroxamic acids in mineral processing is presented. Some basic information on mineral flotation chemistry is provided for the sake of common readers. Adsorption of hydroxamates on several minerals is compared because mostly the mineral flotation studies are preceded with adsorption studies. Usually, hydroxamic acids take the trans conformation about the carbonyl carbon and amine nitrogen bond. However, crystal structures of two aryl hydroxamic acids with cis conformation are furnished. Extension of QSAR approach and molecular modelling, hitherto known in drug design, is also covered to present them as scientific tools for design of mineral collectors that are more selective.