Solubility lead sulfide

Sulfur Polymer Cement. SPC has been proven effective in reducing leach rates of reactive heavy metals to the extent that some wastes can be managed solely as low level waste (LLW). When SPC is combined with mercury and lead oxides (both toxic metals), it interacts chemically to form mercury sulfide, HgS, and lead sulfide, PbS, both of which are insoluble in water. A dried sulfur residue from petroleum refining that contained 600-ppm vanadium (a carcinogen) was chemically modified using dicyclopentadiene and oligomer of cyclopentadiene and used to make SC (58). This material was examined by the California Department of Health Services (Cal EPA) and the leachable level of vanadium had been reduced to 8.3 ppm, well below the soluble threshold limit concentration of 24 ppm (59). 

Healy MA, Harrison PG, Aslam M, et al. 1982. Lead sulfide and traditional preparations Routes for ingestion, and solubility and reactions in gastric fluid. J Clin Hosp Pharmacol 7 169-173. 

Cyanamide pigments are produced from industrial-grade calcium cyanamide which is first dissolved. Sulfide and phosphide impurities are precipitated as iron or lead salts [5.127]—[5.132] or oxidized [5.133] [5.135] and filtered off together with graphite impurities. The pure calcium cyanamide is reacted in an aqueous medium with soluble lead or zinc salts or with a slurry of lead oxide or zinc oxide [5.127], [5.129], [5.133], [5.136]—[5.138]. The pigments are filtered, washed, dried, and ground. Zinc cyanamide [5.139] and pure lead cyanamide are not explosive. An explosion reported during the production of lead cyanamide was caused by contamination with small amounts of acid or nitrates [5.140],... 

Suffide. Lead suilide. plumbous sulfide. (CAS 1314-87-01, PhS. hrownish-hlack precipitate, formed by reaction of soluble lead salt solution and hydrogen suilide or sndium or ammonium suilide. soluble in dilute nitric acid. 

Oleic acid may be obtained from glycerol trioleate, present in many liquid vegetable and animal nondrying oils, such as olive, cottonseed, lard, by hydrolysis. The crude oleic acid after separation of the water solution of glycerol is cooled to fractionally crystallize the stearic and palmitic acids, which are then separated by filtration, and fractional distillation under diminished pressure. Oleic acid reacts with lead oxide to form lead oleate, which is soluble in ether, whereas lead stearate or palmitaie is insoluble, prom lead oleate oleic add may be obtained by treatment with IL 5 (lead sulfide, insoluble solid, formed). With sodium oleate, a soap is formed. Most soaps are mixtures of sodium stearate, palmitate. and oleate. 

Dilute hydrochloric acid or sulfuric acid Silver nitrate Lead acetate Sodium nitroprusside solution Sulfides, S2 Hydrogen sulfide gas is evolved and detected by odor or lead acetate paper Black precipitate of silver sulfide soluble in hot, dilute nitric acid Black precipitate of lead sulfide Transient purple color in the presence of solutions of alkalis... 

SAFETY PROFILE A poison. Flammable by spontaneous chemical reaction, air, moisture, or acid fumes may cause it to ignite. For explosion and disaster hazards, see SULFIDES. To fight fire, use CO2, dry chemical. Reacts violently with phosphorus(V) oxide. Mixtures with lead dioxide, potassium chlorate, or potassium nitrite explode when heated. Incompatible with CI2O, Ca(N03)2, Sr(N03)2, Ca(C103)2, Sr(C103)2, (C103)2. See also BARIUM COMPOUNDS (soluble) and SULFIDES. 

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. 

Hemley et al. (1992) studied the solubility of iron, lead, zinc, and copper sulfides in chloride solutions that were rock-bufifered in pH and in oxygen and sulfur fugacity, in the range 300-700 °C 50-200 MPa. Their results show that iron-, copper-, zinc-, and lead-sulfide mineral solubilities decrease with decreasing temperature and decreasing total chloride (see Figure 2), and with increasing pressure. In nature, the HCl concentration (which is the sum of HC1° and some portion of the ionized and Cl ) in a hydrothermal solution is controlled by equilibria such as... 

Lead compounds such as lead naphthalene tetracarboxylate, lead pyrophosphate, lead stannate, lead sulfide, and others which are not listed in Table 3, were proved to be effective uranium sorbents in sea water 131). However, sorbent materials containing toxic metals must be excluded with respect to sea contamination which would be inevitable even in the case of slight solubility. On the other hand, many metal compounds are decomposed in sea water by hydrolysis and carbonate formation. Among the inorganic sorbents presented in Table 3, hydrous titanium oxide and... 

Hemley, J.J., Cygan, G.L., Fein, J.B., Robinson, G.R. and D Angelo, W.M., 1992. Hydrothermal ore - forming processes in the light of studies in the rock-buffered systems 1. Iron-copper-zinc-lead sulfide solubility relations. Economic Geology, 87 1-22. 

The + 2 oxidation state is dominant in most inorganic compounds. The salts of Pb(II), lead oxides, and lead sulfide are not readUy soluble in water, with the exception of lead acetate, lead chlorate and, to some extent, lead chloride. 

Lead is absorbed from the gastrointestinal tract. The amount of absorbed lead through the digestive system is greatly influenced by stress, fasting and the solubility of the lead compound. As an example, lead acetate is 25 times more soluble than lead sulfide. 

G. Hevesy, F. Paneth. The Solubility of Lead Sulfide and Lead Chromate, 1913. 

Sodium sulfide solution or hydrogen sulfide gas are used as the source of sulfide ions. Solutions of Na, Cdi and K+ will not produce precipitates because their sulfides are water soluble. Zinc sulfide (ZnS) is white, while lead(ll) and silver sulfides (PbS and Ag2S) are black. 

Aluminmn s sulfide salt shows a high degree of solubility, so no precipitation occurs. But at the low pH of the test solution, where the concentration of the sulfate ion is very limited, cations with very small solubility products, e.g., lead sulfide, will precipitate. 

Sulfur and several sulfides, highly insoluble precipitates with solubility products as low as 1.6 X 10 for mercuric sulfide, have been used to concentrate trace metals from water. Sulfur, produced from (NH4)aS and HNO3 ( 0), coprecipitated several metals including mercury. Iron(III) sulfide (also used in a commercial process SULFEX) removes several metals (61) and is better than hydroxide in the presence of EDTA and other chelating agents (62). Lead sulfide has been used to collect silver for aqueous solution (63), molybdenum sulfide to collect arsenic from 2 M hydrochloric acid solution (64), and copper sulfide to concentrate cobalt and zinc from seawater (65). 

Lead in nature occurs in a number of minerals such as galena (lead sulfide), ce-russite (lead carbonate) and anglesite (lead sulfate) none of these dissolve in water. The world production of lead is about 6 million t annually. If societies only used newly mined lead, deposits would be exhausted in a mere 15 years. This limited natural supply of lead and the toxicity of water-soluble lead salts is more than enough... 

F. Lead sulfide (PbS) is a black solid that is sparingly soluble in water but dissolves in concentrated HCl. If such a solution is boiled to dryness, white, crystalline lead chloride (PbCl2) remains. What happened to the sulfide ... 

Moore (M5) reports that excellent separation of traces of lead from small amounts of bismuth can be achieved by adding 0.02 grams of copper to 25 ml of the lead and bismuth in 2N hydrochloric acid and saturating the solution with hydrogen sulfide, gas. The copper sulfide precipitate was then filtered and washed with 2N hydrochloric acid saturated with hydrogen, sulfide. The lead was recovered from the filtrate and bismuth from the precipitate. The lead presumably was kept from precipitation because of formation of soluble lead chloride complexes. 

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