Iron-arsenate

Lead The production of lead from lead sulphide minerals, principally galena, PbS, is considerably more complicated than the production of zinc because tire roasting of the sulphide to prepare the oxide for reduction produces PbO which is a relatively volatile oxide, and therefore the temperature of roasting is limited. The products of roasting also contain unoxidized galena as well as die oxide, some lead basic sulphate, and impurities such as zinc, iron, arsenic and antimony. 

Scott et al. 1995 Rancourt et al. 2001 Thirunavukkarasu et al. 2003). Iron-arsenic coprecipitates have been found in natural environments (Pichler et al. 1999 Frankenberger 2002). 

The mine water to be treated flows from an old adit into the nearby watercourse (Peliteira Creek). Water properties are rather variable, dependent on seasonal variations (Loureiro 2007). Nevertheless, it can be generically described as an acid (pH<4), sulfate and metal-rich solution, especially in iron, arsenic, zinc and manganese. 

Because 1,4-dichlorobenzene is a liver toxin, it probably can interact with other chemicals that are liver toxicants. These toxicants are many, and include ethanol, halogenated hydrocarbons (chloroform, carbon tetrachloride, etc ), benzene, and other haloalkanes and haloalkenes. In addition, 1,4-dichlorobenzene toxicity may also be exacerbated by concurrent exposure with acetaminophen, heavy metals (copper, iron, arsenic), aflatoxins, pyrrolizidine alkaloids (from some types of plants), high levels of vitamin A, and hepatitis viruses. Such interactions could either be additive or S5mergistic effects. 

The surveyed data also indicate that there were net increases in all of the following compounds total dissolved solids, total suspended solids, total organic carbon, total residual chlorine, free available chlorine 2,4-dichlorophenol, 1,2-dichlorobenzene, phenolics, chromium, lead, copper, mercury, silver, iron, arsenic, zinc, barium, calcium, manganese, sodium, methyl chloride, aluminum, boron, and titanium. 

Solubility data (pA sp) for two dozen hexacyanoferrate(II) and hexacyanoferrate(III) salts, and Pourbaix (pe/pH) diagrams for iron-cyanide-water, iron-sulfide-cyanide-(hydr)oxide, iron-arsenate-cyanide-(hydr)oxide, and iron-copper-cyanide-sulfide-(hydr)oxide, are given in a review ostensibly dedicated to hydrometallurgical extraction of gold and silver. " The electrochemistry of Prussian Blue and related complexes, in the form of thin films on electrodes, has been reviewed. ... 

Chemical precipitation is applicable to most heavy metals likely to be found in contaminated gronndwater. Examples of metals that have been removed to a concentration of less than 1 ppm inclnde cadminm, chrominm, nickel, zinc, manganese, copper, tin, iron, arsenic, lead, and mercnry. Chemical precipitation is widely nsed to meet National Pollution Discharge Elimination System (NPDES) reqnirements for the treatment of heavy-metal-containing wastewaters. In many cases, metals precipitation may also be nsed as a pretreatment step prior to discharge of the wastewater to a pnblicly owned treatment works (POTW). 

Abdominal examination may reveal ileus, which is typical of poisoning with antimuscarinic, opioid, and sedative drugs. Hyperactive bowel sounds, abdominal cramping, and diarrhea are common in poisoning with organophosphates, iron, arsenic, theophylline, A phalloides, and A muscaria. 

Iodine is used in various forms in medicine—e.g. tincture of iodine, liquor iodi, iodized cotton, iodized wine, iodized water, oils and syrups iodides of potassium, mercury, iron, arsenic, lead, etc. and as methyl iodide or di-iodide iodoform, CHI3 ethyl iodide, C2H5I iodole, C4I4.NH aristole etc.—largely for external application as an antiseptic. Some iodides are used in photography, and in analytical operations and a considerable amount of iodine is used in the preparation of aniline dyes. 

Iron Monarsenide, FeAs, may be obtained by heating iron in a current of arsenic vapour at 335° to 380° C. 2 by heating a mixture of the elements in a bomb tube at 680° C.,3 or a mixture of iron, arsenious oxide and carbon in an electric arc furnace 4 by the action of fused potassium cyanide on iron arsenate 8 by reduction of the di-arsenide at 680° C. in a current of hydrogen 3 or by dropping a solution of a ferrous salt into an atmosphere of arsine.6... 

Iron Arsenates.—Ferrous Ortkoarsenate, Fe3(As04)3.6H20, is obtained as a white precipitate when ammonium orthoarsenate1 or sodium monohydrogen arsenate 2 is added to an aqueous solution of ferrous sulphate. In the latter ease the reaction is stated to be ... 

Gallagher, P.A., C.A. Schegel, A. Parks, B.M. Gamble, L. Wymer, and J.T. Creed. 2004. Preservation of As(III) and As(V) in drinking water supply samples from across the United States using EDTA and acetic acid as a means of minimizing iron-arsenic coprecipitation. Environ. Sci. Technol. 38 2919-2927. 

Equation 3 is an example of an undesirable reaction because of the solubilization of arsenic. Fortunately, most of it precipitates subsequently as an iron arsenate. 

Fig. 68 Changes in the speciation of iron, arsenic, and uranium compared to pE and pH values during the degradation of organic matter over a period of600 days...

The crude oxide is dissolved in hydrochloric add. To the warm liquor finely divided calcium carbonate is added gradually, with stirring, until no further predpitate is obtained. The precipitate being removed by filtration, the solution is free from iron, arsenic, and silica. The solution is then precipitated with a solution of bleaching powder,2 added slowly with constant stirring until almost the whole of the cobalt is precipitated as black hydrated oxide. By this means practically none of the nickel is thrown down. The precipitate is washed, dried, and calcined to oxide. It is then boiled with sodium carbonate solution to convert any calcium sulphate into carbonate, and after thorough washing, is treated with very dilute hydrochloric acid to remove the calcium carbonate. Finally the oxide is washed, dried, and calcined. 

SYNS ARSENATE of IRON, FERROUS FERROUS ARSENATE (DOT) FERROUS ARSENATE, soUd (DOT) IRON ARSENATE (DOT)... 

AS2F6308 (S) 3FeO AS2O5 (s) Iron Arsenate As2pe308 (s) 3FeO AS2O5 (s)... 

Arsenic is a metallic element (symbol As atomic no. 33), which exists in several allotropic forms. Various ores contain crystalline forms of arsenic salts cobaltite contains cobalt arsenic sulfide mispickel (arsenopyrite) iron arsenic sulfide orpiment arsenic trisulfide proustite (ruby silver ore) silver arsenic sulfide realgar arsenic sulfide and tennantite copper arsenic sulfide. 

Static leaching experiments were done in which the coal waste was shaken with deionized water for 1 to 50 days. The mixtures were then filtered and the filtrate was analyzed for acidity, specific conductance, and trace element content. All these measurements increased with leaching time. In many cases, the leachates were very acidic, with pH values less than 2, indicating that this waste could generate drainages of environmental concern. Iron, arsenic, nickel, manganese, and aluminium had concentrations in the waste effluents that are of... 

Beudantite Lead iron arsenate sulfate hydroxide PbFe3As04S04(0H)6... 

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