Lead, carbonate sulfid

HaS or HI, so as to form lead carbonate, sulfide or iodide oidy on the surface without penetration into the crystal (Ref 22). This treatment will unquestionably reduce the efficiency of LA because it will be contaminated by inert materials l)Solubiliry of LA in water or in 50% alcohol was detd as described in item VII F tinder Lead Azide Plant Analytical Procedures In addn to above listed tests, the various LA s were loaded in M47 caps as intermediate chges together with NOLNo 130 as a primary chge and RDX as a base chge and subjected to the following tests given in the Purchase Description PA-PD-202, with Rev 1 dated 30 Sept 1952 and Amend 1 dated 27 Jan 1953 ... 

HjS or HI, so as to form lead carbonate, sulfide or iodide odly on the surface without penetration into the crystal (Ref 22). This treatment will unquestionably reduce the efficiency of LA because it will be contaminated by inert materials... 

Precipitation is affected by pH, solubiUty product of the precipitant, ionic strength and temperature of the aqueous stream, and the presence of metal complexes. For each metal precipitant, there is an optimum pH where its solubiUty is lowest and hence, the highest removals may be achieved. When an aqueous stream contains various metals, the precipitation process caimot be optimized for each metal, sometimes making it difficult to achieve effluent targets for each. SolubiUty products depend on the form of the metal compound and ate lowest for metal sulfides, reflecting the relative insolubiUty of these compounds. For example, the solubiUty product for lead sulfide [1314-87-0] is on the order of compared to 10 for lead carbonate. Metal... 

Tellur-sfiure, /. telluric acid, -schwefelkohlen-stoff, m. carbon sulfide telluride, CSTe. -sil-ber, n. silver telluride. -silberblei, n. lead silver telluride, Min.) sylvanite. -silber-blende,/. sylvanite stutzite. 

Calculate AH for the reaction of one mole of lead(II) sulfide with oxygen and carbon, forming lead, sulfur dioxide, and carbon monoxide. 

Pigments and dyes provide paint and ink colors. Many highly toxic pigments, such as copper acetate (blue-green), arsenic trisulfide (yellow), and mercury II iodide (red), are no longer used. However, other hazardous pigment compounds, such as lead carbonate, mercury II sulfide, and cadmium sulfide, are still used today. These compounds present a danger to those artists who use their mouths to make a brush more pointed. 

In addition, potential application of materials containing carbon-sulfur bonds in electronic industries has recently provided an impetus for the synthesis of further binary carbon sulfides, leading to the discovery and characterization of C3 S7,... 

A recent report by Haver et al. (H16) described the recovery of lead and. sulfur from a lead sulfide concentrate using ferric sulfate as the leaching reagent. Elemental sulfur was produced during the oxidation of lead sulfide to lead sulfate by hot ferric sulfate solution. The lead sulfate in the re.sidue was changed to acid-soluble lead carbonate by treatment with ammonium carbonate, and ammonium sulfate was a by-product. Hydro-fluosilicic acid dissolved the lead carbonate and an electrolysis step regenerated the HjSiF and deposited 99.9% pure lead metal. The recovery for lead was about 90% and for sulfur, 67%, half as elemental sulfur and the other half as ammonium sulfate. 

Glattfeld and Hanke applied this procedure to the oxidation of maltose hydrate. An aqueous solution of the sugar was shaken with lead carbonate and bromine since lead bromide separated from the reaction mixture, only aeration was necessary to remove the excess bromine, and treatment with silver oxide and hydrogen sulfide removed the last bromide, silver and lead ions. The maltobionic acid was isolated as the calcium salt. Here the neutralization of the hydrobromic acid was beneficial in preventing any hydrolysis of the aldobionic acid. 

Lead rarely occurs as a pure element in the earth. Its most common ore is galena, or lead sulfide (PbS). Other ores of lead are anglesite, or lead sulfate (PbS04) cerussite, or lead carbonate (PbC03) and mimetite... 

Activators Activators selectively react with particles to cause the collector to surface. The classic example, as mentioned above, is the use of copper sulfate for the activation of zinc sulfide so that it can be collected by standard sulfide mineral collectors. Another example is the surfacing of lead carbonate, copper carbonate, and copper oxide with the use of sodium sulfide so that collection is also possible by the sulfide collectors. 

Derivation Roasting and reduction of galena (lead sulfide), anglesite (lead sulfate), and cerussite (lead carbonate). Also from scrap. 

Formation of a cyanoformamidine by treatment of a symmetrical diphenylthiourea with potassium cyanide in alcohol containing lead carbonate, reduction with ammonium sulfide, and ring closure with concentrated sulfuric acid to isatin-2-anil also formed smoothly by ring closure of the cyanoformamidine with aluminum chloride in benzene or carbon disulfide. 

Carbon Dioxide. As the debate of the effect of greenhouse gases rages on, the simple fact remains that carbon dioxide production is one of the known side reactions of most metal-production operations. Carbon is an effective metal reductant. Coke is used to produce pig iron from iron oxide ores and lead from sulfide ores in blast furnaces, carbon electrodes are used to produce aluminum from bauxite leaching products, and coal is used in the reduction of zinc oxide in retorting furnaces. All told, the resulting product of metal reduction is the oxidation of carbon to carbon dioxide. It is important to keep in mind that the production of carbon dioxide has been reduced dramatically since the start of the Industrial Revolution of the late nineteenth-century. This is best exemplified by the history of steel making in the world. 

The metals have the tendency to form compounds of low solubility with the major divalent cations (Pb, Cd being found in natural water. Hydroxide, carbonate, sulfide, and, more rarely, sulfate may act as solubility controls in precipitating metal ions from water. A significant fraction of lead and, to a greater extent, cadmium carried by river water is expected to be in an undissolved form. This can consist of colloidal particles or larger undissolved particles of lead carbonate, lead oxide, lead hydroxide, or other lead compounds incorporated in other components of surface particulate matter from runoff. The ratio of lead in suspended solids to lead in dissolved form has been found to vary from 4 1 in rural streams to 27 1 in urban streams. The US Environmental Protection Agency (USEPA) has reported Maximum Contaminant Levels in water that are permissible to be 0.005 m L for cadmium and 0.015 mg/L of lead. ... 

The recovery of artifacts from the sunken ship, Titanic, shows the results of corrosion over 89 years at 0°C and pH 8.2 under 2.5 miles of water.89 Aided by bacteria and other agents, steel had corroded to give FeO(OH), Fe203, and FeC03. Lead carbonate and lead sulfide were derived from the paint. Brass had corroded to Cu(OFl)Cl. There was a slow conversion of silver to silver chloride. 

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