Antimony extraction

It is recommended that the eompound be fused with a mixture of sodium carbonate (2 parts) and sodium peroxide (1 part) as in the test for Plvoaphoms. Extract the fused mass with water, filter, and acidify with dilute hydrochloric acid. Pass hydrogen sulphide through the hot solution arsenic is precipitated as yellow arsenic sulphide. If antimony is present, it will be precipitated as orange antimony trisulphide. 

Many nonferrous metals can be extracted by reduction smelting, eg, copper, tin, nickel, cobalt, silver, antimony, and bismuth. Blast furnaces are sometimes used for the smelting of copper or tin, but flash and reverberatory furnaces are more common for metals other than lead. 

The standard chemical and biological methods of analysis are those accepted by the JnitedStates Pharmacopeia XXIII as well as the ones accepted by the AO AC in 1995 (81—84). The USP method involves saponification of the sample (dry concentrate, premix, powder, capsule, tablet, or aqueous suspension) with aqueous alcohoHc KOH solvent extraction solvent removal chromatographic separation of vitamin D from extraneous ingredients and colormetric deterrnination with antimony trichloride and comparison with a solution of USP cholecalciferol reference standard. 

Hydrochloric acid digestion takes place at elevated temperatures and produces a solution of the mixed chlorides of cesium, aluminum, and other alkah metals separated from the sUiceous residue by filtration. The impure cesium chloride can be purified as cesium chloride double salts such as cesium antimony chloride [14590-08-0] 4CsCl SbCl, cesium iodine chloride [15605 2-2], CS2CI2I, or cesium hexachlorocerate [19153 4-7] Cs2[CeClg] (26). Such salts are recrystaUized and the purified double salts decomposed to cesium chloride by hydrolysis, or precipitated with hydrogen sulfide. Alternatively, solvent extraction of cesium chloride direct from the hydrochloric acid leach Hquor can be used. 

Another point is related to the high acidity level of the final solution, which leads to certain limitations in the subsequent technological steps. Specifically, the high acidity of the initial solution eliminates any possibility for selective extraction, i.e. sequential separation of tantalum and then of niobium. Due to the high concentration of acids, only collective extraction (of tantalum and niobium together) can be performed, at least at the first step. In addition, extraction from a highly acidic solution might cause additional contamination of the final products with antimony and other related impurities. In order to reduce the level of contaminants in the initial solution, some special additives are applied prior to the liquid-liquid extraction. For instance, some mineral acids and base metals are added to the solution at certain temperatures to cause the precipitation of antimony [455 - 457]. 

The reaction is a sensitive one, but is subject to a number of interferences. The solution must be free from large amounts of lead, thallium (I), copper, tin, arsenic, antimony, gold, silver, platinum, and palladium, and from elements in sufficient quantity to colour the solution, e.g. nickel. Metals giving insoluble iodides must be absent, or present in amounts not yielding a precipitate. Substances which liberate iodine from potassium iodide interfere, for example iron(III) the latter should be reduced with sulphurous acid and the excess of gas boiled off, or by a 30 per cent solution of hypophosphorous acid. Chloride ion reduces the intensity of the bismuth colour. Separation of bismuth from copper can be effected by extraction of the bismuth as dithizonate by treatment in ammoniacal potassium cyanide solution with a 0.1 per cent solution of dithizone in chloroform if lead is present, shaking of the chloroform solution of lead and bismuth dithizonates with a buffer solution of pH 3.4 results in the lead alone passing into the aqueous phase. The bismuth complex is soluble in a pentan-l-ol-ethyl acetate mixture, and this fact can be utilised for the determination in the presence of coloured ions, such as nickel, cobalt, chromium, and uranium. 

Procedure. Dissolve a suitable weight of the sample of lead in 6M nitric acid add a little 50 per cent aqueous tartaric acid to clear the solution if antimony or tin is present. Cool, transfer to a separatory funnel, and dilute to about 25 mL. Add concentrated ammonia solution to the point where the slight precipitate will no longer dissolve on shaking, then adjust the pH to 1, using nitric acid or ammonia solution. Add 1 mL freshly prepared 1 per cent cupferron solution, mix, and extract with 5 mL chloroform. Separate the chloroform layer, and repeat the extraction twice with 1 mL portions of cupferron solution + 5 mL of chloroform. Wash the combined chloroform extracts with 5mL of water. Extract the bismuth from the chloroform by shaking with two 10 mL portions of 1M sulphuric acid. Run the sulphuric acid solution into a 25 mL graduated flask. Add 3 drops saturated sulphur dioxide solution and 4 mL of 20 per cent aqueous potassium iodide. Dilute to volume and measure the transmission at 460 nm. 

V. H. Aprahamian and D. G. Demopoulos, The Solution Chemistry and Solvent Extraction Behaviour of copper, iron, nickel, zinc, lead, tin, Ag, arsenic, antimony, bismuth, selenium and tellurium in Acid Chloride Solutions Reviewed from the Standpoint of PGM Refining, Mineral Processing and Extractive Metallurgy Review, Vol. 14, p. 143,1995. 

The Extraction of Antimony from its ore. rhttp //wwwlevitv.com/alchemv/separati.html1. 

The following photographic documentation of the process of extracting antimony from its ore made by one of my French correspondents and one of his colleagues. He says -"These pictures describe an experiment undertaken a few years ago related to the Dry path of antimony (or Stibnite Path) as followed by E. Canseliet and, I guess (but opinions could differ on this point ) by Fulcanelli. The first group concerns the "liquation", i.e. the preliminary purification of the antimony ore (stibinite). The second series shows the Separation. Except for the ore which came from Bolivia, we worked with commercial products coming from a local chemical dealer."... 

Selenium is extracted as diethyldithiocarbamate complex from the solution containing citrate and EDTA [5]. Ohta and Suzuki [6] found that only a few elements, such as copper, bismuth, arsenic, antimony, and tellurium, are also extracted together with selenium. They examined this for effects of hundredfold amounts of elements co-extracted with the selenium diethyldithiocarbamate complex. An appreciable improvement of interferences from diverse elements was observed in the presence of copper. Silver depressed the selenium absorption in the case of atomisation of diethyldithiocarbamate complex, but the interference of silver was suppressed in the presence of copper. The atomisation profile from diethyldithiocarbamate complex was identical with that from selenide. 

Two ml of citrate buffer (purified by an Fe-APDC precipitation) were added to maintain a pH of 5- 6. The sample was degassed for 100 s prior to the injection of 2 ml of 5% sodium borohydride. The sample was stripped for 300 s. This procedure gives a complete extraction of antimony (III) and no extraction of antimony (V), even in the presence of hundredfold higher concentrations of antimony (V). 

Rozan A variation of the Pattinson process for extracting silver from lead, in which steam is blown through the molten metal. This oxidizes the zinc and antimony, which come to the surface and are removed. 

Salsigne A cyanide process for extracting gold from ores containing arsenic or antimony. Pre-treatment with a lime slurry reduces cyanide losses. 

Antimony is then determined by a spectrophotometric method utilizing crystal violet in which the extract is treated with this chromogenic agent and... 

Two people are responsible for the discovery of tellurium. First, Franz Joseph Muller von Reichenstein (1743—1825), chief inspector of a gold mine in Transylvania (part of Romania), experimented with the ores in his mine between 1782 and 1783. From an ore known as aurum album, he extracted an element that, at first, was thought to be antimony. He sent a sample to Martin Heinrich Klaproth (1743—1817), who 16 years later correctly identified it as a new element and named it tellurium. However, Klaproth gave Franz Joseph Muller credit for the discovery. 

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