EXTRACTION OF INORGANICS

R M Diamond and D G Tuck, Extraction of inorganic compounds into organic solvents. In Progress in Inorganic Chemistry, Vol 2, F A Cotton (Ed), Interscience, New York, 1960... 

Extraction of inorganic compounds into organic solvents. R. M. Diamond and D. G. Tuck, Prog. Inorg. Chem., 1960,2,109-192 (325). 

Diamond, R. M. and Tuck, D. G., Extraction of Inorganic Compounds into... 

Chapters 11 and 12 are the result of separating Chapter 7 from the First Edition into two chapters. Chapter 11 deals specifically with the extraction of inorganic analytes and Chapter 12 deals with organic analyte extraction. 

A majority of soil extractions of inorganic constituents are carried out to determine the metal content of a soil sample. In these cases, it is common to use add extracting solutions. Dilute hydrochloric and sulfuric acids are most commonly used. Nitric acid is an oxidizer, so undesired oxidation can occur during the extraction process using this reagent. Phosphate is a natural... 

The industrial use of solvent extraction of inorganic compounds grew out of the analytical work. As both areas, analytical as well as industrial, needed both better extractants and an understanding of the reaction steps in the solutions in order to optimize the applications, theoretical interpretations of the molecular reactions in the solutions became a necessity, as will be described in later chapters. 

The mechanism of separation of biological molecules such as proteins and amino acids, and the parameters that affect the extraction distribution coefficient and the kinetics of extraction have been studied more extensively than the extraction of inorganic solutes. This is mainly due to the variety of size and structure of these molecules and, furthermore, to the fact that their characteristics may be adversely affected by their contact with solvents and surfactants. 

Li and coworkers synthesized the novel IL l-butyl-3-trimethylsilylimid-azolium hexafluorophosphate and demonstrated its utility for liquid/ liquid extraction of inorganic mercury. Using o-carboxyphenyl diazoamino p-azobenzene as a chelator to form a stable neutral complex with the metal ion, the authors demonstrated selective extraction into the hydrophobic IL phase [19]. When sodium sulfide was added to the IL phase, the mercury ion was back-extracted into the aqueous layer, providing an avenue for recycling the IL. The authors report extraction and back-extraction efficiencies of 99.9 and 100.1%, respectively, for a 5.0 pg/L aqueous mercury standard. The mercury detection limit was 0.01 ng/mL in water and the method was successfully applied to detecting trace mercury in natural water samples. 

While the liquid-liquid extraction of inorganic elements as coordination complexes with thiocyanate ions can be traced back to Skey (1867), the extraction from hydrochloric acid into ether of iron(III) (J. W. Rothe, 1892) or gallium (E. H. Swift, 1924) depends on the formation of solvated acido complexes derived from HMC14 extractions of metal complexes from nitric, thio-cyanic, hydrofluoric, hydrochloric and hydrobromic acids were studied exhaustively by Bock and his collaborators (1942—1956).6... 

Chiarizia, R., Briand, A. 2007. Third phase formation in the extraction of inorganic acids by TBP in n-octane. Solvent Extr. Ion Exch. 25 (3) 351-371. 

The extraction of inorganic species such as Fe [146], and Cu, Pb, As, Se, Hg and Cd [172], from soils was investigated on a pilot plant scale with a view to developing an industrial-scale method for decreasing allowed levels of the metals used to manufacture cement. To this end, kinetic curves for the extraction rate were used that allowed the time... 

Several comprehensive reviews on the extraction of inorganic materials from sea water have already been published. Tallmadge, Butt, and Solomon 7) evaluated methods for recovery of different minerals. Mcllhenny has reviewed the extraction of raw materials and economic inorganic materials from sea water5). The recovery of minerals from the oceans is also discussed by Hanson and Murthy 9), Seetharam and Srinivasan 10), and very recently by Massie U) and Ogata 12). 

Phosphorus is not a TE but a major nutrient element. Nevertheless, fractionation of this element is essential for environmental studies, and hence it seems reasonable to highlight here some relevant SEPs. Four different procedures for the fractionation of P in lake sediment samples have been tested in an interlaboratory study in the framework of the SM T program (Ruban et al., 1999). As a result, a novel scheme based on the Williams protocol (Williams et al., 1976) has been developed aimed at the restoration of lake sediments. The scheme comprises three separate assays (1) sequential extraction of NaOH-extractable (Fe- and Al-bound) and HCl-extractable (Ca-bound) fractions, (2) sequential extraction of inorganic and organic phosphorus and (3) single extraction, after calcination, of concentrated HCl-extractable (total P) fraction (see Table 12.3 for further details). Further discrimination of specific compounds is made feasible by the use of chromatographic and capillary separation techniques as reviewed by Spivakov et al. (1999). 

Work by Ruiz et al. in the analysis of water soluble inorganic phosphates in vegetables, such as tomato, lettuce, marrow, mushroom, celery, cauliflower, chard, onion, carrot, used SPE with Sep-Pak C18 cartridges for removal of organic compounds prior to IC analysis. Spiro and co-workers studied the kinetics of extraction of inorganic anions, including phosphate, from different types of tea into water. 

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