Extraction from sulphate solution

Attempts have also been made to solvent-extract thorium directly from the sulphate liquor obtained by the acid breakdown of monazite. Tributyl phosphate can be used as the solvent provided a large concentration of nitric acid is added to the liquor before extraction. In order to make the process economic, a high proportion of the nitric acid must then be recovered by distillation of the raffinate liquor. Processes are also being developed which are based upon the use of higher alkyl phosphate or amine solvents to extract from sulphate solutions without the addition of nitric acid, as in the case of uranium. For example bis(l-isobutyl 1-3-5 dimethyl-hexyl) amine, di-2-ethylhexyl hydrogen phosphate and Primene JM-T have been used. 

L.J. Lozano, C. Godinez, Comparative study of solvent extraction of vanadium from sulphate solutions by Primene 81R and Alamine. Min. Eng. 16 (2003) 291-294. 

In our previous papers iron removal from sulphate solutions has been studied by precipitation as goethite and by solvent extraction in D2EHPA solutions. In the present paper, jarosite precipitation has been studied. ... 

Leptazol, or l,5 pentamethylenetetrazole, can be extracted from aqueous solution saturated with ammonium sulphate by solvents such as chloroform or carbon tetrachloride but it has a low melting-point to 60°) and is appreciably volatile at 100°, less so at room temperature. It forms complexes with many inorganic salts, some having relatively low solubilities. A method of assay for solutions using mercuric chloride has been proposed by Horsley as the solubility of the leptazol complex in 3-5 per cent mercuric chloride was found to be of the order of 0 01 per cent to 0-02 per cent and allowance for the precipitate is necessary, a method of using two dilutions is employed ... 

In the isolation of organic compounds from aqueous solutions, use is frequently made of the fact that the solubility of many organic substances in water is considerably decreased by the presence of dissolved inorganic salts (sodium chloride, calcium chloride, ammonium sulphate, etc.). This is the so-called salting-out effect. A further advantage is that the solubility of partially miscible organic solvents, such as ether, is considerably less in the salt solution, thus reducing the loss of solvent in extractions. 

CAUTION. Ethers that have been stored for long periods, particularly in partly-filled bottles, frequently contain small quantities of highly explosive peroxides. The presence of peroxides may be detected either by the per-chromic acid test of qualitative inorganic analysis (addition of an acidified solution of potassium dichromate) or by the liberation of iodine from acidified potassium iodide solution (compare Section 11,47,7). The peroxides are nonvolatile and may accumulate in the flask during the distillation of the ether the residue is explosive and may detonate, when distilled, with sufficient violence to shatter the apparatus and cause serious personal injury. If peroxides are found, they must first be removed by treatment with acidified ferrous sulphate solution (Section 11,47,7) or with sodium sulphite solution or with stannous chloride solution (Section VI, 12). The common extraction solvents diethyl ether and di-tso-propyl ether are particularly prone to the formation of peroxides. 

Decant the liquid layer into a 2 5 litre flask, and dissolve the sodium derivative of acetylacetone in 1600 ml. of ice water transfer the solution to the flask. Separate the impiue ethyl acetate layer as rapidly as possible extract the aqueous layer with two 200 ml. portions of ether and discard the ethereal extracts. Treat the aqueous layer with ice-cold dilute sulphimic acid (100 g. of concentrated sulphiu-ic acid and 270 g. of crushed ice) until it is just acid to htmus. Extract the diketone from the solution with four 200 ml. portions of ether. Leave the combined ether extracts standing over 40 g. of anhydrous sodium sulphate (or the equivalent quantity of anhydrous magnesium sulphate) for 24 hours in the ice chest. Decant the ether solution into a 1500 ml. round-bottomed flask, shake the desiccant with 100 ml. of sodium-dried ether and add the extract to the ether solution. Distil off the ether on a water bath. Transfer the residue from a Claisen flask with fractionating side arm (Figs. II, 24, 4r-5) collect the fraction boiling between 130° and 139°. Dry this over 5 g. of anhydrous potassium carbonate, remove the desiccant, and redistil from the same flask. Collect the pure acetji-acetone at 134r-136°. The yield is 85 g. 

Preparation. The mother liquors from strychnine manufacture are concentrated and the alkaloids precipitated as neutral oxalates. The precipitate is dried and extracted with dry alcohol in which the strychnine salt is the more soluble. The less soluble salt dissolved in water is decolorised with charcoal, the alkaloid regenerated with ammonia and purified by crystallisation as the sulphate. According to Saunders, pure brucine may be obtained by slow crystallisation from a solution of the pure hydrochloride in alcoholic ammonia. A method of separation depending on the greater solubility in water of strychnine hydriodide was employed by Shenstone, whilst others have made use of the sparing solubility of strychnine chromate for the removal of small quantities of this alkaloid from brucine. For a large scale process see Schwyzer. ... 

Mix I gram of phenol with i c.c. of dimethyl sulphate and add 4 c.c. of a lo per cent, solution of caustic soda. Warm and shake. The odour of phenol is replaced by that of anisole, which can be extracted from the licjuid by ether (Ullmann s reaction). See Appendix. p. 294. 

Bhaskara Sarma, P. V. R. Reddy, B. R. Liquid-liquid extraction of nickel at macro-level concentration from sulphate/chloride solutions using phosphoric acid based extractants. Miner. Eng. 2002, 15, 461-464. 

Ocana, N. Alguacil, F. J. Cobalt-manganese separation The extraction of cobalt(II) from manganese sulphate solutions by Cyanex 301. J. Chem. Technol. Biotechnol. 1998, 73, 211-216. 

Cotterill [222] has developed a procedure, discussed below, in which the herbicides are extracted from soil with saturated calcium hydroxide solution. After clean-up the residues are ethylated using iodoethane and tetrabutylammonium hydrogen sulphate as counter ion. Liquid-liquid partition and the use of a macroreticular resin column were compared as clean-up steps and the reaction conditions for optimum yield of ethyl ester were evaluated. 

Aznarez et al. [2] have described a Spectrophotometric method using curcumin as chromopore for the determination of boron in soil. Boron is extracted from the soil into methyl isobutyl ketone with 2-methylpentane-2,4-diol. In this method 0.2-lg of finely ground soil is digested with 5ml concentrated nitric-perchloric acid (3 + 1) in a polytetrafluoroethylene lined pressure pump for 2h at 150°C. The filtrate is neutralized with 6M sodium hydroxide and diluted to 100ml with hydrochloric acid 1+l.This solution is triple extracted with 10ml of methyl isobutyl ketone to remove iron interference. This solution is then extracted with 10ml 2-methyl pentane-2,4 diol and this extract dried over anhydrous sodium sulphate. 

Thiophenol.—Benzene sulphochloride (8 g.) is allowed to run in small portions from a dropping funnel into a round-bottomed flask containing 20 g. of finely granulated tin and 50 c.c. of concentrated hydrochloric acid. During the addition of the sulphochloride and until most of the tin has dissolved, the flask, which is fitted with a double neck attachment carrying a reflux condenser, is heated on the boiling water bath. The mercaptan produced is distilled with steam and extracted from the distillate with ether. The ethereal solution is dried over sodium sulphate, the ether is removed by distillation, and the thiophenol which forms the residue is likewise distilled. It passes over as an almost colourless liquid at 173°. 

Solution 1 is prepared from exactly 5 ml of 0.4092% w/v atropine sulphate solution and exactly 1 ml of 2.134% w/v homatropine hydrobromide solution. The solution is basified and extracted, the solvent is removed and the residue is treated with 2 ml of BSA and then diluted to 50 ml with ethyl acetate. Solution 3 is prepared from exactly 2 ml of eyedrops and exactly 1 ml of 2.134% w/v homatropine hydrobromide solution. The solution is basified and extracted, the solvent is removed and the residue is treated with 2 ml of BSA and then diluted to 50 ml with ethyl acetate. 

Filter off the barium sulphate precipitate and evaporate the solution in a porcelain bowl first on a flame up to one-fourth of its initial volume, and then in a water bath until dry, Rapidly cool the hot bowl with cold water to facilitate the separation of the precipitate. Extract the hydroxylamine chloride from the solution, for which end transfer the triturated substance into a flask with a reflux condenser, pour in 30 ml of ethanol, and heat it on an electric stove with an enclosed heating element up to boiling. Pour off the liquid into a beaker and treat the solid substance again with 15 ml of ethanol. Combine the ethanol extracts, filter them through a crucible with a glass filtering bottom, and then evaporate the filtrate in a water bath up to the beginning of crystallization. 

Pour a small amount of copper sulphate, silver nitrate, and potassium manganate solutions into three beakers and drop a small piece of white phosphorus into each of them. In 10 or 15 minutes, extract the phosphorus from the solutions. Dry it as indicated above, put it on an iron plate, and heat it. What happens How do the given salts affect white phosphorus How can the different activity of white and red phosphorus be explained Write the equations of [the [reactions. 

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