Metal separations using aqueous biphasic partitioning systems

Chaiko, David J.; Zaslavsky, Boris Y.; Rollins, Andrew N.; Vojta, Y.; Gartelmann, J.; Mego, W.

doi:10.2172/231396

Cited by 6 publications

(8 citation statements)

References 14 publications

(25 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During the same time frame, applications of ABS to biotransformations have also been the subject of some interest. , In more recent years, increasingly diverse applications of ABS have appeared in the literature. These include applications to the recovery of metal ions and radiochemicals; − applications in the recovery of dyes, drug molecules, and small organic species; − and applications to the recovery of inorganic particles . A yet more recent emerging trend has been the investigation of ABS as an alternative solvent system for chemical reactions.…”

Section: Introductionmentioning

confidence: 99%

Phase Diagram Data for Several PEG + Salt Aqueous Biphasic Systems at 25 °C

2003

View full text Add to dashboard Cite

Phase diagrams determined by the cloud point method at 25 °C, including tie lines assigned from mass phase ratios according to the lever arm rule, are presented for several poly(ethylene glycol) (PEG) + salt aqueous biphasic systems (ABS). The systems include PEG-1000 + K3PO4, PEG-2000 + K3PO4, PEG-3400 + K3PO4, and PEG-2000 in combination with the following salts K2CO3, (NH4)2SO4, Li2SO4, ZnSO4, MnSO4, and NaOH.

show abstract

Section: Introductionmentioning

confidence: 99%

Phase Diagram Data for Several PEG + Salt Aqueous Biphasic Systems at 25 °C

2003

View full text Add to dashboard Cite

show abstract

“…Thus, they can be used for the differential distribution of added solutes. Because of their mild nature, which is consonant with the maintenance of macromolecular structure, such systems have been employed for the separation of biological macromolecules and particles for over 40 years. − Recently, these systems have shown promise as unique, environmentally benign alternatives to traditional solvent-based biphasic systems for the separation of metal ion species, − small organic molecules, − and lignins from cellulose in the paper pulping process. − …”

Section: Introductionmentioning

confidence: 99%

“…Separation processes are ubiquitous in the chemical industry, and as a result, increasing attention is being shown to these processes, particularly with regard to their environmental impact. Thus, more environmentally benign separation processes are being developed and utilized in industry such as solid-phase extraction (SPE), supercritical fluid extraction (SFE), and room-temperature ionic liquids (RTILs). , Aqueous biphasic systems represent safe, nontoxic, nonflammable, nonvolatile, and relatively environmentally benign extraction media that can be utilized in the separations of a wide range of molecular species ranging from metal ions through small organic molecules to macromolecules and even particles, both in industrial and analytical separations and in environmental applications. ,− …”

Section: Introductionmentioning

confidence: 99%

Solvent Properties of Aqueous Biphasic Systems Composed of Polyethylene Glycol and Salt Characterized by the Free Energy of Transfer of a Methylene Group between the Phases and by a Linear Solvation Energy Relationship

Willauer

Huddleston

Rogers

2002

Ind. Eng. Chem. Res.

105

139

View full text Add to dashboard Cite

Aqueous biphasic systems (ABSs) composed of poly(ethylene glycol) (PEG) and salt have been examined as potential environmentally benign solvents for liquid/liquid extraction. These systems might also represent an alternative to traditional solvent/water systems used in quantitative structure-activity relationships (QSARs). For the application and design of these systems, it is important to have a thorough understanding of the nature of the solvent and its interactions with the solute, and thus, PEG/salt ABSs have been characterized to this end by a variety of methods. The relative hydrophobicities of several PEG/salt ABSs composed of different molecular weights of PEG (1000, 2000, and 3400) and a variety of inorganic salts [K 3 PO 4 , K 2 CO 3 , (NH 4 ) 2 -SO 4 , Li 2 SO 4 , MnSO 4 , ZnSO 4 , and NaOH] were measured by the free energy of transfer of a methylene group ∆G CH 2 . These results indicate that the relative hydrophobicity of a PEG/salt ABS is a function of only the degree of phase divergence of the biphasic system as expressed by the difference in polymer concentration between the phases [delta poly(ethylene glycol) (∆PEG), delta ethylene oxide monomer (∆EO)] or the tie line length (TLL). The distributions of a wide range of solutes differing in structure and functionality were also measured in PEG/salt ABSs, and the results were compared to the corresponding 1-octanol/water partition coefficients. These data were used to develop a linear free energy relationship (LFER) based on Abraham's generalized solvation equation, enabling a direct comparison to be made between the solvent properties of PEG/salt ABSs and those of traditional solvent/water systems used, for example, in the determination of log P. Similar comparisons are also enabled with the properties of certain aqueous micellar systems.

show abstract

“…Patenting activity in this field is very diverse. While the use of alkylammonium surfactants has become common practice, several groups dedicate their research to the development of heat resistant organoclays [51][52][53], others make efforts to facilitate the exfoliation by incorporating two or more intercalants [54,55] or polymeric ammonium [56] and some seek solutions for very specific applications such as improved flame retardancy [57].…”

Section: Organoclays For Melt Intercalation Methodsmentioning

confidence: 99%

Patenting Activity in Manufacturing Organoclays for Nanocomposite Applications

Naveau¹,

Detrembleur²,

Jérôme³

et al. 2009

MATS

View full text Add to dashboard Cite

For the last two decades, intensive research has been focused on developing reinforced polymers with incorporation of nanometric fillers. Amongst the different types of nanofillers, those based on layered silicates (commonly known as clays), have been most widely investigated. Dispersing clay sheets on a nanoscopic scale (so-called exfoliation) indeed allows materials with enhanced thermal, mechanical, rheological, flame retardancy and barrier properties to be produced. However, the nanocomposite performances are strongly dependent upon the extent of clay exfoliation. In order to enhance the compatibility between the pristine clay, hydrophilic, and the polymer, hydrophobic, and to achieve a good delamination of the nanolayers, an organo-modification of the clay is most usually necessary. This mini-review will provide an outline of patenting activity in the field of manufacturing organoclays through ionic exchange. The variety of organic modifiers and the diverse processing techniques will be detailed, aiming to extract the most relevant organoclays for successful nanocomposite formation at industrial scale.

show abstract

Metal separations using aqueous biphasic partitioning systems

Cited by 6 publications

References 14 publications

Phase Diagram Data for Several PEG + Salt Aqueous Biphasic Systems at 25 °C

Phase Diagram Data for Several PEG + Salt Aqueous Biphasic Systems at 25 °C

Solvent Properties of Aqueous Biphasic Systems Composed of Polyethylene Glycol and Salt Characterized by the Free Energy of Transfer of a Methylene Group between the Phases and by a Linear Solvation Energy Relationship

Patenting Activity in Manufacturing Organoclays for Nanocomposite Applications

Contact Info

Product

Resources

About