Thiacalixarenes as selective carriers for the transport and separation of gold,palladium and platinum by using supported liquid membrane systems

摘要

From an environmental and economic viewpoint,there remains a need to discover more selective and effective extractant for toxic and valuable metals from waters and soils.The challenge is to find complexants that selectively extract commercially useful metals from a mixture and allow them to be released in a pure form.In view of these considerations,we have tested some calixarenes as carriers for noble metals.Calixarenes are macrocy-clic molecules composed of phenolic units linked by methylene groups.A new family of these metacyclophanes,namely thiacalixarenes,which present sulfur atoms in place of the usual methylene has recently emerged.