Simultaneous extraction

The procedure of simultaneous extracting-spectrophotometric determination of nitrophenols in wastewater is proposed on the example of the analysis of mixtures of mono-, di-, and trinitrophenols. The procedure consists of extraction concentrating in an acid medium, and sequential back-extractions under various pH. Such procedures give possibility for isolation o-, m-, p-nitrophenols, a-, P-, y-dinitrophenols and trinitrophenol in separate groups. Simultaneous determination is carried out by summary light-absorption of nitrophenol-ions. The error of determination concentrations on maximum contaminant level in natural waters doesn t exceed 10%. The peculiarities of application of the sequential extractions under fixed pH were studied on the example of mixture of simplest phenols (phenol, o-, m-, />-cresols). The procedure of their determination is based on the extraction to carbon tetrachloride, subsequent back-extraction and spectrophotometric measurement of interaction products with diazo-p-nitroaniline. 

Since the extraction is slow, it is advisable to divide th material into several portions and carry out a number of simultaneous extractions. The extractor used was a modified Soxhlet arranged so that the extractor tube is heated by the vapor o the solvent (Org. Syn. 16, 69, Note 3). 

At first, the reaction was investigated in batch mode, by use of different ionic liquids with wealdy coordinating anions as the catalyst medium and compressed CO2 as simultaneous extraction solvent. These experiments revealed that the activation of Wilke s catalyst by the ionic liquid medium was clearly highly dependent on the nature of the ionic liquid s anion. Comparison of the results in different ionic liquids with [EMIM] as the common cation showed that the catalyst s activity drops in the order [BARF] > [Al OC(CF3)2Ph 4] > [(CF3S02)2N] > [BFJ . This trend is consistent with the estimated nucleophilicity/coordination strength of the anions. 

Figure 15-12 is a schematic illustration of a technique known as acid volatile sulfides/ simultaneously extracted metals analysis (AVS/SEM). Briefly, a strong acid is added to a sediment sample to release the sediment-associated sulfides, acid volatile sulfides, which are analyzed by a cold-acid purge-and-trap technique (e.g., Allen et ai, 1993). The assumption shown in Fig. 15-12 is that the sulfides are present in the sediments in the form of either FeS or MeS (a metal sulfide). In a parallel analysis, metals simultaneously released with the sulfides (the simultaneously extracted metals) are also quantified, for example, by graphite furnace atomic absorption spectrometry. Metals released during the acid attack are considered to be associated with the phases operationally defined as "exchangeable," "carbonate," "Fe and Mn oxides," "FeS," and "MeS."... 

Fig. 15-12 Schematic illustration of the acid volatile sulfides (AVS)/simultaneously extractable metal (SEM) analysis. Refer to the text for details.

Allen, H. E., Fu, G. and Deng, B. (1993). Analysis of acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) for the estimation of potential toxicity in aquatic sediments. Environ. Toxicol. Chem. 12,1441-1453. 

The superiority of extractive hydrolysis over acid hydrolysis with respect to its productivity, yield, raw materials, and waste streams, for the transformation of drug intermediates (e.g. for Primaxin) in formate ester form to the corresponding alcohol, has been effectively demonstrated by King et al. (1985). They carried out the hydrolysis of the relevant formate ester with simultaneous extraction of the desired product from the undesired impurities by two-phase reaction/extraction with a base. 

The concept of extractive reaction, which was conceived over 40 years ago, has connections with acid hydrolysis of pentosans in an aqueous medium to give furfural, which readily polymerizes in the presence of an acid. The use of a water-immiscible solvent, such as tetralin allows the labile furfural to be extracted and thus prevents polymerization, increases the yield, and improves the recovery procedures. In the recent past an interesting and useful method has been suggested by Rivalier et al. (1995) for acid-catalysed dehydration of hexoses to 5-hydroxy methyl furfural. Here, a new solid-liquid-liquid extractor reactor has been suggested with zeolites in protonic form like H-Y-faujasite, H-mordenite, H-beta, and H-ZSM-5, in suspension in the aqueous phase and with simultaneous extraction of the intermediate product with a solvent, like methyl Aobutyl ketone, circulating countercurrently. 

Solvent extraction. Extraction of neonicotinoid insecticides from water is a simple process involving saturation with sodium chloride and extraction with diethyl ether, dichloromethane or ethyl acetate. This extraction procedure will allow the simultaneous extraction of all neonicotinoids. 

Several other useful modifications of calciothermic reduction have been successfully developed for the preparation of this neodymium-bearing magnetic alloy. One of these is reduction-extraction which involves the reduction of neodymium sesquioxide (Nd203) with calcium in a molten calcium chloride-sodium chloride salt bath at 750 °C and the simultaneous extraction of the reduced metal into a molten neodymium-zinc or neodymium-iron alloy pool. The neodymium-zinc alloy product is treated in vacuum to remove zinc and produce neodymium metal, while the neodymium-iron alloy is itself the end product of... 

Advantages Low cost No grinding Broad applicability High b.p. solvent contamination of analyte Low investment Simple equipment Simultaneous extractions in series Low investment Simple equipment Rapid Economic solvent use Good reproducibility Low investment Simple equipment Economical Simple equipment Not traumatic Almost solvent free Concentrated analyte Rapid Low temperatures Rapid Automated Simultaneous extraction Low solvent use Rapid User friendly Automated Sequential extractions Not analyst labour intensive... 

Ability to simultaneously extract analytes of wide polarity range... 

MPE In situ to extract VOCs and treatment using aboveground processes Simultaneous extraction of VOCs... 

Allen HE, Fu G, Boothman W, et al. 1994. Determination of acid volatile sulfide and selected simultaneously extractable metals in sediment. PB94-183852. 

Gonzalez S, Petrovic M, Barcelo D (2004) Simultaneous extraction and fate of linear alkylbenzene sulfonates, coconut diethanol amides, nonylphenol ethoxylates and their degradation products in wastewater treatment plants, receiving coastal waters and sediments in the Catalonian area (NE Spain). J Chromatogr A 1052(1-2) 111-120... 

Soltanpour P.N., Schwab A. P. A new soil test for simultaneous extraction of macro- amd micro-nutrients in alkaline soils. Commun Soil Sci Plant Anal, 1977 8 195-207. 

P. Rivalier, J. Duhamet, C. Moreau, and R. Durand, Development of a continuous catalytic heterogeneous column reactor with simultaneous extraction of an intermediate product by an organic solvent circulating in countercurrent manner with the aqueous phase, Catal. Today, 24 (1995) 165-171. 

Procedures using chelation followed by extraction have been described for manganese using the 8-hydroxy-quinoline-chloroform system [432,444], Dithiocarbamate systems can simultaneously extract manganese, along with other trace metals under suitable conditions [445-447]. 

Imperial Smelting A process for simultaneously extracting zinc and lead from sulfide ores, developed and commercialized by the Imperial Smelting Corporation at Avonmouth, UK, after World War II, and now widely used. Based on an invention by L. J. Derham in which the vapors emerging from a reducing kiln are rapidly quenched in a shower of droplets of molten lead. The first trial was made in 1943 but most of the development work was done from 1945 to 1947. Eleven plants were operating in 1973. 

An analogous system to the cation sensors is the use of optically nonactive anion ionophores together with a pH-sensitive chromophore for the anion sensing. In this system, simultaneous extraction of H+ and anion X- from the aqueous solution into an organic phase results in protonation of the chromophore anion C, e.g. 

In situ derivativization and supercritical fluid extraction has been used for the simultaneous extraction and determination of butyl tin and phenyltin compounds in soils and sediments [73]. 

Yang S, Cha J, Carlson K (2005) Simultaneous extraction and analysis of 11 tetracycline and sulphonamide antibiotics in influent and effluent domestic wastewater by solid-phase extraction and liquid chromatography-electrospray ionization tandem mass spectrometry. J Chromatogr A 1097 40-53... 

Instead, foodstuffs are a greater challenge due to the complexity of their matrices and the low natural concentration of vitamins in food. The different stability and the numerous vitamers present in foodstuffs required dedicated extraction procedures. The simultaneous extraction of vitamin B B2 has been performed in a unique step several times. However their detection, if MS is not applied, usually needs to be performed under different conditions, which means carrying out two different chromatographic analyses. 

Hiraga, Y., N. Nakata, H. J in, et al. Effect of the rice bran-derived phytosterol cycloartenol ferulic acid ester on the central nervous system. Arz-neim-Forsch 1993 43(7) 715-721. Mao, X. H., R. P. Xu, S. G. Wang, et al. Simultaneous extraction of oryzanol and yazhouning from crude rice bran oil. Patent-Faming Zhuanli Shenqing Gongkai Shuomingshu—1,067,448 1992 14 pp. 

System (3) described the use of stable-isotope-dilution mass spectrometry for the simultaneous determination of cortisol, cortisone, prednisolone, and prednisone in plasma [177]. Cortisol, cortisone, prednisolone, and prednisone were simultaneously extracted from acidified plasma on a Sep-Pak Ci8 cartridge. The column was eluted with methanol, the eluent evaporated, and the residue compounds reacted to their bismethylenedioxy-3-heptafluoro-n-butyryl derivatives by treatment with formaldehyde and heptafluoro-n-butyric anhydride. The derivatives were... 

Dual-phase extraction accelerates site remediation by simultaneously extracting contaminated liquid and soil vapor from the subsurface. The technology can be used to treat soil or groundwater contaminated with chlorinated solvents and petroleum hydrocarbons. 

HF Mass transfer model Simultaneous extraction and strip- [27]... 

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