Copper® chloride-sulfur dioxide

Even prior to Pasteur, alcohol content determination was important as a basis for local, import, and export taxes. Other important applications of accurate wine analysis have been to detect and to accurately determine food additives now there are legal reasons for analyzing wines for sulfur dioxide, organic chloride or bromide, sodium, cyanide, diglucoside pigments, various insecticides, fungicides, etc. Winery control calls for analytical determination of iron, copper, protein, total acidity, pH, tartaric, malic and lactic acids, etc. Finally, quality control... 

ARENESULFONYL CHLORIDES Phosphoryl chloride. Sulfur dioxide-Copper(I) chloride. 

T riphenyl-thiophenyl (8 ) was synthesized by substituting the diazonium group of 2,4,6-triphenylaniline by sulfur dioxide/copper(I)-chloride followed by reduction of the disulfide 9145 Mild oxidation gave only the disulfide 9, (a very short lived... 

Tables 2.3-2.6 and Fig. 2.2 give historic data on corrosion resistance of zinc classified subjectively by environment. The qualitative terms used by authors clearly have different corrosion significance in different parts of the world. Some work for which atmospheric pollution data is available is given in Table 2.7A together with a supplement. Table 2.7B. Averages of six l-year tests in the worldwide ISOCORRAG series, still in progress, have been published, however (Knotkova, 1993) the full data cover steel, copper, and aluminum as well as zinc. The interpretation of measurements of atmospheric sulfur dioxide and chloride is not clear-cut different measurement techniques can give substantially different results, and the relationship between corrosion effects and the particular method of measurement requires further interpretation.

Preparation. Thiophosgene forms from the reaction of carbon tetrachloride with hydrogen sulfide, sulfur, or various sulfides at elevated temperatures. Of more preparative value is the reduction of trichi oromethanesulfenyl chloride [594-42-3] by various reducing agents, eg, tin and hydrochloric acid, staimous chloride, iron and acetic acid, phosphoms, copper, sulfur dioxide with iodine catalyst, or hydrogen sulfide over charcoal or sihca gel catalyst (42,43). 

For operations producing 30,000 tons or less of copper annuaHy, hydrometaHurgy offers an alternative to smelting that avoids problems associated with sulfur dioxide recovery and environmental controls. Techniques include the Anaconda oxygen—ammonia leaching process, the Lake Shore roast-leach-electrowin process, and ferric chloride leaching processes for the treatment of copper sulfides. AH the facHities that use these techniques encountered serious technical problems and were shut down within a few years of start-up. 

The most efficient processes in Table I are for steel and alumintim, mainly because these metals are produced in large amounts, and much technological development has been lavished on them. Magnesium and titanium require chloride intermediates, decreasing their efficiencies of production lead, copper, and nickel require extra processing to remove unwanted impurities. Sulfide ores produce sulfur dioxide (SO2), a pollutant, which must be removed from smokestack gases. For example, in copper production the removal of SO, and its conversion to sulfuric acid adds up to 8(10) JA g of additional process energy consumption. In aluminum production disposal of waste ciyolite must be controlled because of possible fiuoride contamination. 

Diazonium salts can be converted to sulfonyl chlorides by treatment with sulfur dioxide in the presence of cupric chloride. The use of FeS04 and copper metal instead of CUCI2 gives sulfinic acids (ArS02H). See also 13-18. 

Longmaid-Henderson A process for recovering copper from the residue from the roasting of pyrites to produce sulfur dioxide for the manufacture of sulfuric acid. The residue was roasted with sodium chloride at 500 to 600°C the evolved sulfur oxides and hydrochloric acid were scrubbed in water and the resulting solution was used to leach the copper from the solid residue. Copper was recovered from the leachate by adding scrap iron. The process became obsolete with the general adoption of elemental sulfur as the feedstock for sulfuric acid manufacture. 

To a solution of 1200 g. of copper sulfate and 400 g. of sodium chloride in 4 1. of water at 60-70° is added a concentrated solution of 200 g. of (90-95 per cent) sodium bisulfite (prepared if desired by saturating with sulfur dioxide a solution of 100 g. of sodium carbonate). The white precipitate of cuprous chloride is filtered off, sucked dry as rapidly as possible, and suspended in a mixture of 2 1. of water and 1500 cc. of concentrated hydrochloric acid (Note 1). 

Mercuric iodide is precipitated by mixing solutions containing 6.8g of mercuric chloride and 8.3g of potassium iodide. The washed material is dissolved in 50ml of water containing a similar quantity of potassium iodide, and mixed with a saturated aqueous solution of 12g of copper sulfate 5-hydrate. A stream of sulfur dioxide is passed into the mixture until precipitation is complete and the supernatant liquid is very faintly colored. 

Many other industrial methods are now employed e.g. one starts (22) with anthranilic acid which is diazotised and treated with liquid sulfur dioxide in presence of copper as catalyst. The sulphinic acid derivative thereby obtained is treated with chlorine in alkaline solution and sulfonyl chloride so obtained is treated with ammonia and heated. 

Concentrated sulfuric acid Silver nitrate Copper sulfate Mercury (II) chloride Methylene blue Potassium hexacyanoferrate (II) and iron (II) sulfate Fast evolution of sulfur dioxide and precipitation of pale yellow sulfur Black precipitate of silver Red precipitate of copper Gray precipitate of mercury Decolorization in cold solution White precipitate of dipotassium iron (II) hexacyanoferrate (II) turns from white to Prussian blue... 

Raw stock for the direct synthesis of methylchlorosilanes, methylchlo-ride, has such impurities as moisture, methyl alcohol, oxygen, sulfur dioxide, methylenechloride, dimethyl ether, carbon oxide and dioxide, etc. Most of them negatively affect the synthesis of methylchlorosilanes harmful impurities are chemisorbed on the active centres of contact mass and foul the copper catalyst, which naturally inhibits the reaction of methyl-chloride with contact mass. A similar situation is observed in the direct synthesis of ethylchlorosilanes. 

The original literature2 suggests that copper(II) chloride dihydrate can be used as a catalyst, since it is reduced by the sulfur dioxide to copper(I). It has been noted on several occasions that cataiytically inactive mixtures result. If copper(II) chloride dihydrate is used, it is expedient to add copper(I) chloride (lg) to ensure efficient catalysis in the early stages of the reaction. 

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