Selectivity, separation and

Finally, selective separation and dewatering of one suspended substance in a slurry containing different minerals or precipitates is possible by selectively adsorbing a magnetic material (usually hydrophobic) onto a soHd that is also naturally or chemically conditioned to a hydrophobic state. This process (Murex) was used on both sulfide ores and some oxides (145). More recently, hydrocarbon-based ferrofluids were tested and shown to selectively adsorb on coal from slurries of coal and mineral matter, allowing magnetic recovery (147). Copper and zinc sulfides were similarly recoverable as a dewatered product from waste-rock slurries (148). 

Eigure 13.25 was published in Chemical Engineering Science, 61, Gounaris, C., Eloudas, C.A., Wei, J., Rational design of shape selective separation and catalysis - I concepts and analysis, p. 7933-7948, Copyright Elsevier (2006)... 

J.F. Keenedy, G.O. Phillips, PA. Williams. Cellulosics Materials for Selective Separations and Other Technologies. Horwood, New York, 1993. 

Amino acids in general Crown ether and open chain polymer of transtetra-hydro furan, 2,5-bis acetylene unit SLM Highly selective separation and enantiomeric resolution [98,99]... 

Stepnowski, R, Nichthauser, Mrozik, W., and Buszewski, B., Usefulness of jt- -n aromatic interactions in the selective separation and analysis of imidazolium and pyridinium ionic liquid cations. Anal. Bioanal. Chem., 385, 1483-1491,2006. 

At the same time, it is perhaps not unreasonable to ask coal petrographers to refrain from undue criticism unless they are prepared to help us select, separate, and characterize suitable materials for chemical research. 

R.J. Valus, R. Eshraghi, A.E. Velikoff and J.C. Davis, High Pressure Facilitated Membranes for Selective Separation and Process for the Use Thereof, US Patent 5,057,641 (October, 1991). 

Parthasarathy, N., J. Buffle, N. Gassama, and F. Cuenod. 1999. Speciation of trace metals in waters Direct selective separation and preconcentration of free metal ion by supported liquid membrane. Chem. Anal. 44 455 170. 

Modeling and optimization of pertraction into emulsion in HF contactors is discussed in refs. [77, 138]. The design and optimization of a network of HF contactors with minimum cost that permits the selective separation and recovery of anionic pollutants, for example, Cr(VI), using BLME process for groundwater remediation is presented in ref. [139] and for waste-water treatment in ref. [140]. 

Also, use of functionalized surfactants as the reversed micellar formers (8) tailored for specific components of mixtures should be synthesized and evaluated. Further development of specific affinity ligand co-surfactants for such tailored extractions should also lead to selective separation and purification of biomaterials (377). 

Selective Separation and Removal of Hydrocarbon Vapors from Gas Mixtures.240... 

Teramoto M, Ito N, and Matsumoto H. Selective separation and concentration of carbon dioxide by flowing Uquid membranes. Kagaku Kogaku Ronbunshu, 1990 16(6) 1234-1240. 

Microfiltration processing for clarification and defatting of cheese whey, for selective separation and concentration of micellar caseins from milk for various purposes, for fractionation of caseins and their peptides, for recovery of native whey proteins from milk, for gentle sterilization of milk to produce extended shelf fife liquid milk and cheese milk, for fractionation of globular milk fat and its components, for the reduction of microorganisms in cheese brine, and for the removal of colloidal particles in membrane cleaning solutions. 

Supported liquid membranes, consisting of an organic solution of -octyl(phenyl)-A,iV-diisobutylcarbamoylmethylpho-sphine oxide (CMPO) and tributyl-phosphate (TBP) in decalin, were capable of selective separation and concentration of actinide and lanthanide ions from aqueous nitrate feed solutions and from synthetic nuclear wastes where the strip solution is a mixture of formic acid (FA) and hydroxylammonium formate (HAF) [106,107]. TBP is added to CMPO to improve its solubility in aliphatic diluents. Although low concentration of nitric acid was initially used as the strippant solution, a gradual... 

The ability of ion-exchanger membranes to act as a separation wall, along with the chemical and electrochemical properties of the ion exchangers, provides manifold opportunities toward selective separation and movement of ions. The principal phenomenon in any ion-exchanger membrane is Donnan coion exclusion. Consider an ion-exchanger membrane that separates two solutions containing ions (both cation and anion) of different concentration. If the ions were without any charge, these concentration differences... 

Ashraf, M. W., Mian, A. (2006). Selective separation and preconcentration studies of chromium(VI) with Alamine 336 supported liquid membrane. Toxicol. Environ. Chem., 88, 187-96. 

Solute transport through the LM enhances by water-immiscible species, dissolved in the solvent (water immiscible also) and selectively interacted with solutes. These species are named carriers and transport is facilitated, or membrane-mediated, or carrier-enhanced, or... (authors use different terms for the same phenomenon). Most LM carriers are originally extractants developed for solvent extraction processes. The reader can find their descriptions in the Solvent Extraction Handbooks, for example [88, 89]. Many new carriers are developed specially for LM (see Section 4). The use of LM with carriers offers an alternative to solvent extraction for selective separation and concentration of metal ions from dilute solutions. 

Selective separation and concentration of both cations and anions using water-soluble polymer solutions LM as carriers and hoUow-fiber units (artificial kidneys) as membrane barrier were tested. The authors termed the process as affinity dialysis [74]. Hollow fiber units of Spectrum Medical Industries, Inc. with fibers of 5000 molecular weight cutoff and 150 cm surface area from Spectrapor were used in the experiments. 

A big number of publications were appeared last years in research of WSP-metal ion interactions [111]. Interactions of metal ions with WSP are mainly due to electrostatic forces and the formation of coordinating bonds. Other weak interactions may appear such as trapping metal ions in the bulk of the polymer phase. The author stated that WSP are very perspective for selective separation and concentration (enrichment) of metal ions from the treated diluted solutions (wastewaters, desalination of sea water). 

The subtraction method is widely used in gas chromatography (GC) for the qualitative and quantitative analysis of complex mixtures. It is a modification of the method of selective separation and is based on selective removal of one or a group of components from the test mixture. Removal (subtraction) may be achieved either by a chemical reaction leading to the formation of involatile (or, on the contrary, super-volatile, according to the experimental conditions) compounds from a number of components of the mixture being analysed, or by physical methods leading to the formation of a new involatile (e.g., adsorption) phase for a number of components. 

Many different trace/matrix separation procedures are also applied prior to the ICP-MS determination, or even on-line (e.g. Muller and Heumann 2000). ID finds increasing application in combination with ICP-MS, thereby reducing the problems of analyte losses in sample preparation, but not the problem of interferences in the ICP-MS measurements (e.g., Yi and Madusa 1996) and that of contamination during sample preparation. Schuster and Schwarzer (1998) have described a new very versatile online capable column t/m-separation and preconcentration procedure for the selective separation and preconcentration of Pd even from solutions containing high concentrations of the other PGM. Moldovan et al. (2003) recently published another method for on-line preconcentration and determination of Pd using ICP-MS. 

Chajduk-Maleszewska E., Dybcz3mski R. Selective separation and preconcentration of trace amounts of Pd on Duolite ES 346 resin and its use for the determination of Pd by NAA. Chemia Analityczna 2004 49 281-297. 

Biocatalytic processes for the manufacturing of complex or sensitive molecules require highly selective separation and purification methods. The in situ separation of inhibitory or toxic byproducts or the shifting of unfavourable equilibria are additional aims of bioprocess control technologies. In situ product removal advances both the control of biocatalytic processes and the recovery of target molecules. 

Aires-Barros MR, Cabral JMS (1991) Selective separation and purification of two lipases firom Chromobacterium viscosum using AOT reversed micelles. Biotechnol Bioeng 38 1302-1307... 

Urtiaga A., Bringas E., Mediavilla R., and Ortiz L, The role of liquid membranes in the selective separation and recovery of zinc for the regeneration of Cr(III) passivation baths, J. Membr. Sci. 356, 88, 2010. 

---