Crystallization Cuprous chloride

INTRODUCTION This data sheet presents information on single crystal cuprous chloride. 

Cuprous cyanide solution. The most satisfactory method is to dissolve the cuprous cyanide (1 mol) in a solution of technical sodium cyanide (2 5-2-6 mols in 600 ml. of water). If it is desired to avoid the preparation of solid cuprous cyanide, the following procedure may be adopted. Cuprous chloride, prepared from 125 g. of copper sulphate crystals as described under 1 above, is suspended in 200 ml. of water contained in a 1-litre round-bottomed flask, which is fitted with a mechanical stirrer. A solution of 65 g. of technical sodium cyanide (96-98 per cent.) in 100 ml. of water is added and the mixture is stirred. The cuprous chloride passes into solution with considerable evolution of heat. As the cuprous cyanide is usually emplo3 ed in some modification of the diazo reaction, it is usual to cool the resulting solution in ice. 

One, the CLEAR process, was investigated by Duval Corporation near Tucson, Arizona (29). It involves leaching copper concentrated with a metal chloride solution, separation of the copper by electrolysis, and regeneration of the leach solution in a continuous process carried out in a closed system. Elemental sulfur is recovered. Not far from the Duval plant, Cypms Mines Corporation operated a process known as Cymet. Sulfide concentrates undergo a two-step chloride solution leaching and are crystallized to obtain cuprous chloride crystals. Elemental sulfur is removed during this stage of the process. 

The following description is taken from U.S. Patent 3,116,203. A stirred solution of 75 g of 2-amino.2 -nitrobenzophenone in 700 ml of hot concentrated hydrochloric acid was cooled to 0°C and a solution of 21.5 g of sodium nitrite in 50 ml of water was added in the course of 3 hours. The temperature of the suspension was kept at 2° to 7°C during the addition. The resulting clear solution was poured into a stirred solution of 37 g of cuprous chloride in 350 ml of hydrochloric acid 1 1. The solid which had formed after a few minutes was filtered off, washed with water and recrystallized from ethanol. Crystals of 2-chloro-2 -nitrobenzophenone melting at 76° to 79°C were obtained. 

In a dry, 1-1., two-necked flask, equipped with a mechanical stirrer and a reflux condenser fitted with a drying tube, are placed 17.8 g. (0.100 mole) of anthracene (Note 1), 27.2 g. (0.202 mole) of anhydrous cupric chloride (Note 2), and 500 ml. of carbon tetrachloride (Note 3). The reaction mixture is stirred and heated under reflux for 18-24 hours. The brown cupric chloride is gradually converted to white cuprous chloride, and hydrogen chloride is gradually evolved. At the end of the reaction the cuprous chloride is removed by filtration, and the carbon tetrachloride solution is passed through a 35-mm. chromatographic column filled with 200 g. of alumina (Note 4). The column is eluted with 400 ml. of carbon tetrachloride. The combined eluates are evaporated to dryness to give 19-21 g. (89-99%) of 9-chloroanthracene as a lemon-yellow solid, m.p. 102-104° (Note 5). Crystallization of the product from petroleum ether... 

The copper is crystallized out as cuprous chloride, which is then reduced with hydrogen in a fluidized bed reactor. Developed by Cyprus Mines Corporation, successor to the Cyprus Metallurgical Processes Corporation, which developed Cymet (1). See also CLEAR. 

A. Preparation of the cuprous chloride solution. A solution of 1250 g. (5 mols.) of crystallized copper sulfate and 325 g. (5.6 mols.) of sodium chloride in 4 1. of hot water is prepared in a x 2-1. flask. The flask is fitted with a mechanical stirrer, and an alkaline solution of sodium sulfite (265 g. of sodium bisulfite and 17 5 g. of sodium hydroxide in 2 1. of water) is added during a period of five to ten minutes. The mixture is allowed to cool to room temperature and washed by decantation. The cuprous chloride is obtained as a white powder, which, however, darkens on exposure to the air. The crude product is dissolved in 2 kg. of commercial 28 per cent hydrochloric acid (sp. gr. 1.14) and the solution is used in the following preparation. 

The liquor from the first reaction is used as a pregnant liquor to be fed to electrowinning cells. An important electrical current benefit is realized in that it is only necessary to convert cuprous copper (Cu+) to copper rather than the conventional electrowinning process where cupric copper ( - ) is converted to copper. In an alternative process developed by Cymet (6), the cuprous chloride is crystallized from this liquor by cooling. The cuprous chloride is later reduced to copper in a furnace using hydrogen. 

Dissolve 20 g. of cuprous chloride, CuCl, in the least possible volume of concentrated hydrochloric acid. Cool the solution in ice and slowly add 500 cc. of concentrated ammonia. Keeping the temperature at 0°, add 55 g. of carbon disulfide and shake vigorously at frequent intervals. After standing some 6 days in an ice box at approximately 0°, shining green crystals of the thio-carbonate separate from the solution. Filter off these crystals, wash them with cold water, and quickly dry them on paper. The potassium salt can be made with slight modifications of these directions. 

The arsenide Cu5As.2 has been prepared by passing a current of carbon dioxide and arsenic vapour over finely divided copper heated to the temperature of boiling sulphur 11 by the action of copper on arsenic trichloride or on arsenic dissolved in hydrochloric acid 12 and by the action of cuprous chloride on arsenic. Lustrous regular crystals of density 7-56 are obtained. These tarnish on exposure to air. When heated it loses arsenic and yields Cu3As, which at a higher temperature also decomposes. Cu5As2 dissolves in nitric acid. It is readily attacked by chlorine or bromine.13... 

A. Preparation of Cuprous Hydroxide.—Cuprous chloride is prepared from a solution of 500 g. (2 moles) of crystallized copper sulfate and 150 g. (2.55 moles) of sodium chloride in 2.5 1. of water (Org. Syn. 3, 33) by the gradual addition of sodium sulfite (from no g. of sodium bisullite). After decanting the supernatant solution, the precipitate of cuprous chloride is added to a solution of 350 cc. of 6 N sodium hydroxide in r 1. of water contained in the 4-I. beaker in which the main synthesis is to be performed, the last portion of solid cuprous chloride being washed in with 1 1. of water. After vigorously stirring for a few minutes, the heavy precipitate of deep orange-colored cuprous hydroxide is permitted to settle and the supernatant... 

All metallic chlorides, except silver chloride and mercurous chloride, are soluble in H.O. but lead chloride, cuprous chloride and thallium chloride are only slightly soluble. Metallic chlorides when heated melt, and volaiilize or decompose, e.g.. sodium chloride, mp 804 (2 calcium, strontium, barium chloride volatilize at red heal magnesium chloride crystals yield magnesium oxide residue and hydrogen chloride cupric chloride yields cuprous chloride and chlorine. Sec also Chlorine Chlorinated Organics. Halides Hypochlorites and Sodium Chloride. 

When a crystal of pure silicon is embedded in copper and exposed to methyl chloride at 350° C., the interface between the two solids is seen to recede, and both copper and silicon are removed from the point at which they are in contact or in close proximity. The fact that either element is a catalyst for the removal of the other suggests that the mechanism depends upon mutual interaction, rather than upon adsorption, for example. To find out what happened to the copper, thin films of evaporated copper on glass were heated in an atmosphere of methyl chloride, and it was found that approximately half of the copper was transported in the form of a volatile labile compound, whereas the other half remained in the form of a transparent layer of crystals of cuprous chloride. The first step therefore appears to be... 

Normally, copper does not react with hot concentrated hydrochloric acid, but the periodic addition to the boiling liquid of some drops of nitric acid, or a few crystals of potassium chlorate, induces the ready formation of a clear solution of cuprous chloride (p. 262). As a result of electrolytic action, the presence of platinum also facilitates the solution of copper in hydrochloric acid, the platinum being the cathode and the copper the anode. 

Cuprous chloride is characterized by its power of absorbing carbon monoxide, its solution in either hydrochloric add or ammonia being extensively employed for this purpose in gas-analysis. Contact of a concentrated solution of cuprous chloride in hydrochloric acid with carbon monoxide causes precipitation of the carbonyl-compound in white, crystalline flakes. The ready oxidation of the crystals by atmospheric oxygen renders direct analysis difficult, the first correct results being obtained by Jones4 in the year 1899. He proved the composition to correspond with the formula CuCl,CO,2HaO, and his view has been confirmed by the work of Manchot and Friend.5... 

Potassium cuproferrocyanide, K2Cu2Fe(CN)6, is prepared 1 by boiling cuprous cyanide with a solution of potassium ferrocyanide containing a little potassium sulphite or by boiling cuprous chloride or potassium cuprous cyanide with potassium ferrocyanide solution. When rapidly cooled, the solution yields colourless cubes, but the crystals are liable to undergo partial oxidation, turning yellow or brown in colour. 

Suzuki, Y, Fujita, T., Hayashi, Y. and Okayasu, H. (1989 ). Novel crystal type copper phthalocyanine blue pigment—obtained fromphthalic anhydride, urea, cuprous chloride, titanium tetrachloride and sulphophthalic acid. Sumitomo Chemical Co. Ltd. Patent JP 1153756. Chem. Abstr., Ill, 235057y. [267]... 

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