Caesium Extraction

Shen and Ii [149] extracted caesium (and rubidium) from brine samples with 4-tert-butyl-2-(a methyl-benzyl) phenol prior to atomic absorption spec-trometric determination of the metal. 

Caesium Cs complexed with 4-tetrabutyl-2(a-methyl benzyl) phenol and solvent extracted AAS [149]... 

The ferrocyanide precipitate containing 137caesium is ignited at < 400 °C, the residue is extracted with boiling water, then evaporated and a solution of the residue in acetic acid is treated to precipitate caesium (as Cs3Bi2l9) for /3-counting. 

Riel [67] studied in situ extraction combined with y-ray spectrometry in an underwater probe for the determination caesium and chromium in seawater. 

Uses Of the Stassfurt salts.—The magnesium compounds in the Stassfurt salts are used for the preparation of magnesium and of its salts. The potash salts are an essential constituent of many fertilizers used in agriculture, etc. 22 and potassium chloride is the starting-point for the manufacture of the many different kinds of potassium salts used in commerce—carbonate, hydroxide, nitrate, chlorate, chromate, alum, ferrocyanide, cyanide, iodide, bromide, etc. Chlorine and bromine are extracted by electrolysis and other processes from the mother liquids obtained in the purification of the potash salts. Boric acid and borax are prepared from boracite. Caesium and rubidium are recovered from the crude carnallite and sylvite. 

Lithium, rubidium, and caesium.—F. C. Robinson and C. C. Hutchins 7 extracted all three alkalies—lithium, rubidium, and caesium—by decomposing the mineral with fluorspar in the following manner ... 

Precipitate with aq. ammonia. Evaporate the soln. down to about 100 c.c., and filter the ot liquid so as to remove calcium sulphate. The cone. soln. is sat. with ammonium alum and allowed to stand for some time. The mixed crystals of potassium, rubidium, and oeesium alums and of lithium salt are dissolved in 100 c.c. of distilled water and recrystal-lized. The recrystallization is repeated until the crystals show no spectroscopic reaction for potassium or lithium. The yield naturally depends on the variety of lepidolite employed. 100. grms of an average sample gives about 10 grms. of crude crystals and about 3 grms. of the purified caesium and rubidium alums. For the purification of caesium and rubidium salts, see the chlorides. The mother-liquors are treated with an excess of barium carbonate, boiled, and filtered. The filtrate is acidified with hydrochloric acid, and evaporated to dryness. The residue is extracted with absolute alcohol in which lithium chloride is soluble, and the other alkali chlorides are sparingly soluble. 

The sample, introduced in a solid form, is bombarded by caesium ions. The first mass analyser is used to extract negative ions at selected masses. The ions are then accelerated through a potential difference of several megavolts to eliminate isobaric... 

Ccesium Niobates.—Fusion of niobium pentoxide and caesium carbonate and extraction of the melt with water yields monoclinic crystals which have the composition 4Cs20.3Nb205.14H20, and which are iso-morphous with the rubidium salt. Addition of alcohol to the aqueous solution furnishes crystals of 7Cs2O.6Nb2O5.80H2O. ... 

Rubidium Niobates.—When niobium pentoxide is fused with rubidium carbonate and the melt is extracted with water, fine, silky needles of composition 3Rb20.4Nb205.9 Ha0 are left behind. Concentration of the filtrate yields monoclinic crystals of 4Rb20.3Nba0B. 14H20, which are isomorphous with the corresponding tantalum salt and with the corresponding caesium niobate and tantalate. a b c= 0-8815 1 1-0491 j3=95° 53. It slowly loses some of its water on exposure to- air.3... 

Caesium Tantalates.—Fusion of tantalum pentoxide with caesium carbonate and extraction with water yields monoclinic crystals of the 4 3 salt, 4Cs20.3Taa05.14H20 addition of alcohol to its aqueous solution precipitates the 7 6 salt, 7Cs20.6Ta205.38H20.4... 

Rais, J., Selucky, P, Kyrs, M. Extraction of caesium into nitrobenzene in the presence of univalent polyhedral borate anions. J. Inorg. Nucl. Chem. (1976), 38 (7), 1376-1378. 

GC isotope ratio mass spectrometry [7] and GC using a caesium bromide thermionic detector [8] have been used to determine, respectively, carboxylic ethers in apples and tetraethyl pyrophosphate in chloroform-acetone extracts of crops in amounts down to 0.01 ppm. 

H. citelli, H. diminuta and H. microstoma, one of which is mitochondrial DNA (mtDNA) (394). The mtDNA of H. diminuta has been isolated (118) and has been shown to be a typical circular molecule. The characteristics of H. diminuta DNA are shown in Table 6.11. In contrast, E. multilocularis and E. granulosus produced two distinct DNA bands after fractionation in caesium chloride, but there was no evidence that the DNA from either band represented mtDNA (493). There is presumably so little mtDNA in comparison to nuclear DNA in these organisms that it is completely masked in preparations of total DNA by this method. That this is the case has been shown by a recent study (976), where a different procedure, based on the selective precipitation of nucleic acids by cetyltrimethylammonium bromide (CTAB), was employed to extract mtDNA from isolated mitochondria. Some 300 g and 50 g, respectively, of Taenia spp. and Echinococcus sp. tissue yielded approximately only 1 ng mtDNA. 

SK 23) (Table 2) using a modified hexadecylt-rimethylammonium bromide (CTAB) extraction protocol (Doyle and Doyle 1990 Lange 1997). Nuclear DNA was purified by ultracentrifugation through a caesium chloride—ethidium bromide density gradient (Lange 1997). This DNA was used to create enriched microsatelhte libraries... 

Preparation.—The main source of rubidium compounds is the residual mother-liquor obtained in the extraction of potassium chloride from carnallite. The solution contains rubidium-carnallite, RbCl,MgCI2, a substance transformed by addition of aluminium sulphate into rubidium-alum, RbAl(S04)8,12H20. Separation from the potassium and caesium salts also present is effected by fractional crystallization of the alum,8 of the chloroplatinate 8 Rb2PtCl8, of rubidium-iron-alum,4 and of the double chloride with stannous chloride5 or with antimony trichloride.6... 

Cs (a) Extraction as caesium tetraphenylborate into amyl acetate. Back-extraction with 3 M HCl. (b) After separation of alkali ions, Ru and rare-earth elements, precipitation of Cs as CsAl (S04)2. 

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