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Fundamental Studies Of Metal Ion Extraction Into Ionic Liquids By Macrocyclic Polyethers, James Lee Wankowski

Theses and Dissertations

The liquid-liquid extraction (LLX) of metal ions from aqueous media into ionic liquids (ILs) by macrocyclic polyethers has proven to be an efficient and selective, but complex approach to their separation. Partitioning in these systems has previously been described using a so-called ‘three-path’ model comprising three distinct extraction pathways: neutral complex / ion pair extraction, exchange of the IL cation for a metal-extractant complex, and exchange of the metal ion for a hydronium ion bound to the extractant. The balance of these three paths has been reported to be affected by several characteristics of the LLX system, including the structure …

Extraction Of Indicator Dyes Into Imidazolium-Based Ionic Liquids, Sarah Oplawski

Theses and Dissertations

Among the major classes of water pollutants, dyestuffs have proven to be particularly problematic, both in terms of the quantities released to the environment and the difficulties involved in their recovery from aqueous solution. Each year, textile mills worldwide discharge millions of gallons of dye-laden effluents, leading to significant adverse environmental impact as a consequence of the high chemical oxygen demand and toxicity of these effluent streams. For this reason, there has been considerable interest in the development of a means by which to remove dyes from aqueous waste streams. To accomplish this, textile mills generally employ a combination of …

Anion Effects In The Extraction Of Metal Ions Into Room-Temperature Ionic Liquids (Rtils), Sarah Lynn Garvey

Theses and Dissertations

As part of a broader program directed at the development of improved approaches to the removal of actinides and heat-producing fission products from spent nuclear fuel, the fundamental aspects of the partitioning of selected metal ions between aqueous solution and various room-temperature ionic liquids (ILs) containing a neutral extractant have been investigated.

Prior work has shown that in contrast to the partitioning of alkaline earth cations into conventional solvents in the presence of a crown ether, which is known to proceed via a single pathway (i.e., neutral complex extraction), their extraction into an IL is often a complex, multi-path process …