Antimony crude

A mixture is made of the antimony ore or of antimony crude with the metal or its oxide, in such proportion as will yield one-tenth of the metal in the ore as charged into a reverberatory furnace, a rotatory furnace, or a crucible. The auriferous antimony thus... 

Crude lead contains traces of a number of metals. The desilvering of lead is considered later under silver (Chapter 14). Other metallic impurities are removed by remelting under controlled conditions when arsenic and antimony form a scum of lead(II) arsenate and antimonate on the surface while copper forms an infusible alloy which also takes up any sulphur, and also appears on the surface. The removal of bismuth, a valuable by-product, from lead is accomplished by making the crude lead the anode in an electrolytic bath consisting of a solution of lead in fluorosilicic acid. Gelatin is added so that a smooth coherent deposit of lead is obtained on the pure lead cathode when the current is passed. The impurities here (i.e. all other metals) form a sludge in the electrolytic bath and are not deposited on the cathode. 

Roh-alkohol, m. crude (or raw) alcohoL -analyse, /. rough or approximate analysis, -antimon, n. crude antimony, -arbeit, /, (Metal.) ore smelting, -asbest, m. crude asbestos. -aufbereitung, /. preliminary preparation, -benzol, n. crude benzene, benzol (or benzole), -blei, n. crude lead, -blende, /. (Mining) crude blende, -block,... 

Nickel aluminate, a spinel, has long been known to trap nickel. Metals like arsenic(19), antimony(20-21) and bismuth(20) are known to passivate transition elements and can be used to decrease and coke make. Sulfur is also a known inhibitor for nickel therefore, higher sulfur-containing crudes may be a little less sensitive to nickel poisoning. In our work we also found that nickel at low concentrations is actually a slight promoter of the cracking reaction when incorporated into a molecular sieve (Figure 17). 

Antimony may bo obtained in the pure condition by reducing, with charcoal, the oxide formed by the action of nitric acid upon crude antimony. 

Forman s tastes in alchemical texts were unrefined and his transcriptions informed more by happenstance than deliberation. He copied texts reputedly ancient and modern, English and Arabic, transmutational, medical, and spiritual. Of cako explicitly praised the medicinal virtues of alchemical preparations. When cako (crude antimony in Suchten s text) was taken from the mine, the author (Suchten) explained, it needed to be purged and cleansed in a series of four operations in order to reduce or mature it into progressively purer... 

In either case the crude metal is treated with an excess of hydrochloric acid, when the tin, zluc, bismuth, copper, and iron are dissolved, whilst the arsenic and antimony will be separated the former volatilized in the form of terhydride of arsenic, and the latter partly deposited as a black powder in the liquid, and partly dispelled as antlmomde of hydrogen. The solution is filtered, and the liquid concentrated at a boiling temperature, and strong nitrio acid in excess added, after which the evaporation is continued to dryness. The tin is thus obtained in the state of binoxide, which should he treated with a little hydrochloric acid, then filtered, washed thoroughly, and (hied, mixed with charcoal, and reduced at a whita heat in a charoool-Iincd crucible. 

The writings of Sylvius were first published between 1659 and 1674, all on medical subjects primarily, unless we except his brief treatise on Chemical Medicines,10 which is practically confined to the various medicinal compounds of antimony— flowers, liver, regulus, glass, antimony diaphoreticum, butter of antimony, the latter made by distilling crude antimony (that is sulphide) with mercury sublimate (that is mercuric chloride). These compounds were, however, all known by 1600 and well summarized in pseudo-Basilius s (Tholden s) Currus Tri-umphalis Antimonii. 

The bomb contents are digested with concentrated hydrochloric acid, and material still undissolved is then digested with potassium hydroxide and hydrogen peroxide. A crude separation is made by a sulfide precipitation from the combined digestion solutions. The sulfides are dissolved in aqua regia, the solution is evaporated, and antimony in the residue is reduced to antimony (III) with hydroxylamine hydrochloride. The sample, in ammonium thiocyanate-hydrochloric acid medium, is loaded onto a Dowex 2 column (SCN" form). Arsenic and other impurities are eluted with aliquots of more dilute ammonium thiocyanate-hydrochloric acid solutions. Antimony is eluated with sulfuric acid and fixed in solution by addition of hydrochloric acid. The activity of the solution caused by the 0.56 MeV y-ray of 2.8-day 122Sb is counted. 

An Intimate mixture of 25g stibnite, llg iron powder or filings, 2.5g anhydrous sodium sulfate, and 0.6g charcoal is placed in a covered crucible and heated about 20 minutes with a Meker burner so that the fusion mixture softens but does not quite melt This is determined by momentarily stirring with an iron rod. The melt is allowed to cool and the crucible is broken. A mass of crude fused antimony weighing about 15g is found at the bottom this is mechanically cleaned and then washed with hot water. 

Metals passivation allows refiners to maximize the charge of lower value feeds. Injection of antimony into the Phillips Sweeny, Texas HOC decreased unit hydrogen production and decreased the process gas compressor speed about 500 rpm. This enabled the refinery to increase throughput 10% and process a more difficult to crack feedstock (14). Fifteen percent of Oriente crude from Ecuador was blended into the Phillips Borger, Texas refinery crude slate with the use of metals passivation at its HOC. Metals in the HOC feed and on the HOC catalyst increased significantly, but yield of hydrogen was still less than it had been prior to metals passivation (6). 

Hexachloro-l,3-difluoropropane (CCI2FCCI2CCI2F). 0 In a round-bottomed flask equipped with an air-cooled reflux condenser a mixture of 1500 g. of octachloropropane, 560 g. of antimony, trifluoride, and 75 g. of antimony pentachloride is heated for five hours on a steam bath. A further quantity of 100 g. of antimony pentachloride is then added in small portions, and the heating is continued for twenty hours. The reaction mixture, which gradually becomes homogeneous, is allowed to cool before it is poured into aqueous acid, then is washed and dried. The crude product amounts to 1092 g., from which about 750 g. of difluoride is obtained by fractional distillation at 90 mm. The boiling. point at 760 mm. is 194°, and the freezing point is 29.8°. 

It is not very difficult to recover stibnite from other minerals because the melting point of this antimony mineral is low (546 °C). Heating in the range of 550 to 600 °C results in selective melting of the stibnite, which can be collected as crude concentrate. Roasting in air produces Sb203 that can be reduced with coke. Another method is to reduce the Sb2S3... 

The preparation of trimethylantimony diiodide is identical to that of trimethylantimony dichloride up to the point of the addition of chlorine. Instead of a gas inlet tube, an addition funnel is mounted on the flask containing the ice-cold distillate of ethyl ether and trimethylstibine. For a reaction carried out on the basis of 0.25 mol of anhydrous antimony(III) chloride, a solution of 63,5 g. (0.25 mol) of iodine in 400 ml. of ethyl ether is prepared. This solution is added dropwise to the cold distillate. Stirring is maintained and the addition is continued until the color of iodine persists. The precipitate of trimethylantimony diiodide is filtered off on a fritted Buchner fuimel and washed with ethyl ether. The jdeld of the crude product is 47.7 to 65.3 g. (45.0 to 61.8% of theoretical based upon antimony (III) chloride). The diiodide may be recrystallized from ethanol. Anal. Calcd. for (CH3) 3Sbl2 Sb, 28.95 C, 8.55 H, 2.16. Found Sb, 29.31 C, 8.16 H, 2.25. The checkers report that the foregoing syntheses are also satisfactory using one-half the amounts prescribed. 

COCIF may be prepared by the passage of a gas stream of chlorine(I) fluoride and an excess of carbon monoxide at -18 C into an iron reaction vessel, with the exclusion of air and moisture. The gaseous reaction product is then condensed into a quartz vessel and the crude product distilled through, and from, antimony powder. The yield was found to vary between 85 and 90% (based upon CIF), and was greater if the reaction was performed more slowly the main contaminants were COF and COClj [1194]. Only a ten percent yield of COCIF was obtained by reaction of CIF 3 and CO (diluted with dinitrogen) at -180 C over activated charcoal [1196a],... 

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