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Potassium borates carbonate

There are several salts that behave in this way at atmospheric temperatures, the more important being ammonium acetate potassium bromate, carbonate, cyanide, ferricyanide, ferrocyanide, iodate, and permanganate disodium hydrogen phosphate and sodium borate and carbonate.4 In the case of potassium chlorate the points L and S appear to be practically coincident, whilst for the majority of salts the point S lies somewhere to the left of L, namely at S —that is to say, saturation occurs before the limiting concentration is reached. Generally speaking, at the ordinary temperature, concentrated solutions of salts are less corrosive than distilled water—that is, the point S lies below the level of A, exceptions being 5 ammonium sulphate, aluminium... [Pg.73]

The reactivity of titanium dioxide toward acids is very dependent on the temperature of the reaction mixture. It may be slowly dissolved by boiling concentrated sulfuric acid, with the dissolution rate being promoted by the addition of ammonium sulfate. Titanium dioxide may be readily dissolved by hydrofluoric acid. The material is completely insoluble in aqueous alkalies, but is readily dissolved in molten sodium (or potassium) hydroxide, carbonate, or borate. An equimolar molten mixture of sodium carbonate and sodium borate is partially effective as a dissolution medium. [Pg.662]

Sodium or potassium hydroxide is occasionally used as eluent in nonsuppressed IC. The hydroxide ion has a high conductivity, so the conductivity falls when other anions are eluted. The reason that this eluent is not much used is that the affinity of the hydroxide ion for the exchanger is low. High concentrations of hydroxide must be used, or long elution times must be accepted. Hydroxide eluents are used for the chromatography of anions of very weak acids borate, carbonate, cyanide, silicate, sulfide. These anions cannot be detected by suppressed chromatography. [Pg.2289]

In buffered solution, the DPPH radical can show variations in its stability. Al-Dabbas et al. (2007) found that in methanol solution containing acetate buffer (pH 5.0), the absorbance of the DPPH radical was not reduced in a wide range of concentrations examined (0.01-0.2 mmol L ), while in phosphate buffer (pH 7.0), a reduction of the DPPH radical absorbance was observed at concentrations above 0.05 mmol L. In other studies, Ozcelik et al. (2003) evaluated the variation in stability of the DPPH radical after 120 min. The absorbance of DPPH radical in potassium biphthalate buffer (pH 4.0) decreased by 25% in methanol solution and by -45% in acetone solution. DPPH radical in sodium bicarbonate buffer (pH 7) was stable in an acetone system (less than 10% reduction), but an -30% decrease occurred in the absorbance in a methanol system. DPPH radical in potassium carbonate-potassium borate-potassium hydroxide buffer (pH 10) was stable in a methanol system (less than 10% reduction), but a decrease of -70% occurred in the absorbance in an acetone system. Thus, the stability of DPPH in pH buffer solution mainly depends on the types of buffer and solvent used. [Pg.551]

DEKTAL DEVELOPER KODAK FIXER KODAK SHORT STOP POTASSIUM ALUM POTASSIUM BICARBONATE POTASSIUM BICHROMATE POTASSIUM BORATE POTASSIUM BROMATE POTASSIUM BROMIDE POTASSIUM CARBONATE POTASSIUM CHROMATE POTASSIUM CHLORATE POTASSIUM CHLORIDE POTASSIUM CYANIDE POTASSIUM DICHROMATE POTASSIUM FERRICYANIDE POTASSIUM FERROCYANIDE POTASSIUM FLUORIDE POTASSIUM HYDROXIDE POTASSIUM NITRATE POTASSIUM PERBORATE POTASSIUM PERCHLORATE POTASSIUM PERMANGANATE. 10% POTASSIUM SULFATE PROPANE PROPANE GAS PLATING SOLUTIONS BRASS CADMIUM COPPER GOLD INDIUM LEAD NICKEL RHODIUM SILVER TIN ZINC... [Pg.154]

Phosphata Ester Oils (C) Potassium Bicarbonate IBI Potassium Borate IC) Potassium Bromids (C) Potassium Carbonate IS) Potassium Chlorate (C) Potassium Chloride (C) Potssium Chromate (SI Potassium Cyanide (C) Potassium Oichromate (S) Potassium Ferricyanide IS) Potassium Hydroxide (SI Potassium Hypochlorite IS) Potassium Nitrate (Cl Potassium Oxalate IS) Potassium Permanganate IS) Potassium Sulfate IC) Potassium Sulfite ( 1 Prtstone (C)... [Pg.156]

The Catacarb process, which was disclosed by Eickmeyer (1962), is licensed by Eickmey-er and Associates of Prairie Village, Kansas. For most applications the Catacarb process utilizes a catalyzed hot potassium carbonate solution however, potassium borate solutions are used for the removal of hydrogen sulfide in the absence of carbon dioxide (Gangriwala and Chao, 1985). The solutions contain undisclosed additives that catalyze absorption and desorption of acid gases, particularly carbon dioxide. The additives, which include a corrosion inhibitor, are claimed to have no effect on reformer or methanation catalysts that the purified gas may pass through downstream of the Catacarb absorber (Morse, 1968). [Pg.363]

Potassium Acetate Potassium Acid Sulfate Potassium Acid Tartrate Potassium Antimonate Potassium Bicarbonate Potassium Bichromate Potassium Bisulfate Potassium Bisulfite Potassium Bitartrate Potassium Borate Potassium Bromate Potassium Bromide Potassium Carbonate Potassium Chlorate Potassium Chloride Potassium Chromate Potassium Cyanide Potassium Dichromate Potassium Ferricyanide Potassium Ferrocyanide Potassium Fluoride Potassium Hexacyanoferrate (III) Potassium Hydrogen Carbonate Potassium Hydrogen Sulfate Potassium Hydrogen Sulfite Potassium Hydroxide Potassium Hypochlorite Potassium Hyposulfite Potassium lodate Potassium Iodide Potassium Manganate Potassium Nitrate Potassium Perborate Potassium Perchlorate Potassium Permanganate Potassium Peroxydisulfate Potassium Persulfate... [Pg.3479]

The cmde phthaUc anhydride is subjected to a thermal pretreatment or heat soak at atmospheric pressure to complete dehydration of traces of phthahc acid and to convert color bodies to higher boiling compounds that can be removed by distillation. The addition of chemicals during the heat soak promotes condensation reactions and shortens the time required for them. Use of potassium hydroxide and sodium nitrate, carbonate, bicarbonate, sulfate, or borate has been patented (30). Purification is by continuous vacuum distillation, as shown by two columns in Figure 1. The most troublesome impurity is phthahde (l(3)-isobenzofuranone), which is stmcturaHy similar to phthahc anhydride. Reactor and recovery conditions must be carefully chosen to minimize phthahde contamination (31). Phthahde [87-41-2] is also reduced by adding potassium hydroxide during the heat soak (30). [Pg.484]

The analytical chemistry of titanium has been reviewed (179—181). Titanium ores can be dissolved by fusion with potassium pyrosulfate, followed by dissolution of the cooled melt in dilute sulfuric acid. For some ores, even if all of the titanium is dissolved, a small amount of residue may still remain. If a hiU analysis is required, the residue may be treated by moistening with sulfuric and hydrofluoric acids and evaporating, to remove siUca, and then fused in a sodium carbonate—borate mixture. Alternatively, fusion in sodium carbonate—borate mixture can be used for ores and a boiling mixture of concentrated sulfuric acid and ammonium sulfate for titanium dioxide pigments. For trace-element deterrninations, the preferred method is dissolution in a mixture of hydrofluoric and hydrochloric acids. [Pg.134]

Sodium, 22 700 ppm (2.27%) is the seventh most abundant element in crustal rocks and the fifth most abundant metal, after Al, Fe, Ca and Mg. Potassium (18 400 ppm) is the next most abundant element after sodium. Vast deposits of both Na and K salts occur in relatively pure form on all continents as a result of evaporation of ancient seas, and this process still continues today in the Great Salt Lake (Utah), the Dead Sea and elsewhere. Sodium occurs as rock-salt (NaCl) and as the carbonate (trona), nitrate (saltpetre), sulfate (mirabilite), borate (borax, kemite), etc. Potassium occurs principally as the simple chloride (sylvite), as the double chloride KCl.MgCl2.6H2O (camallite) and the anhydrous sulfate K2Mg2(S04)3 (langbeinite). There are also unlimited supplies of NaCl in natural brines and oceanic waters ( 30kgm ). Thus, it has been calculated that rock-salt equivalent to the NaCl in the oceans of the world would occupy... [Pg.69]

The poor efficiencies of coal-fired power plants in 1896 (2.6 percent on average compared with over forty percent one hundred years later) prompted W. W. Jacques to invent the high temperature (500°C to 600°C [900°F to 1100°F]) fuel cell, and then build a lOO-cell battery to produce electricity from coal combustion. The battery operated intermittently for six months, but with diminishing performance, the carbon dioxide generated and present in the air reacted with and consumed its molten potassium hydroxide electrolyte. In 1910, E. Bauer substituted molten salts (e.g., carbonates, silicates, and borates) and used molten silver as the oxygen electrode. Numerous molten salt batteiy systems have since evolved to handle peak loads in electric power plants, and for electric vehicle propulsion. Of particular note is the sodium and nickel chloride couple in a molten chloroalumi-nate salt electrolyte for electric vehicle propulsion. One special feature is the use of a semi-permeable aluminum oxide ceramic separator to prevent lithium ions from diffusing to the sodium electrode, but still allow the opposing flow of sodium ions. [Pg.235]

Alum Borax Natron Iron vitriol Mineral Mineral Mineral Mineral or synthetic Sulfate of aluminum and other metals (e.g., potassium alum) Hydrated sodium borate Natural mixture sodium carbonate and sodium bicarbonate Hydrated iron sulfate... [Pg.393]

Kiss [8] examined various techniques for the efficient separation and preconcentration of boron from marine sediments. Alkaline fusion with potassium carbonate was used to render boron reactive, even in the most resistant silicate minerals. Fusion cakes were extracted with water and borate was isolated by Amberlite XE-243 boron-selective resin. Borate was determined spectrophotometrically, following elution with 2 mol L 1 hydrochloric acid. Either the carminic acid complex (620nm), formed in sulphuric acid (94%) or sulphuric acetic acid (1 4), or the azomethine hydrogen ion association complex (415nm) formed at pH5.2, were used for borate measurement. [Pg.315]

In most commercial processes, borax is obtained from lake brines, tincal and colemanite. The primary salt constituents of brine are sodium chloride, sodium sulfate, sodium carbonate and potassium chloride. The percent composition of borax as Na2B40 in brine is generally in the range 1.5 to 1.6%. Borax is separated from these salts by various physical and chemical processes. The brine solution (mixed with mother liquor) is subject to evaporation and crystahzation for the continuous removal of NaCl, Na2C03 and Na2S04, respectively. The hot liquor consists of concentrated solution of potassium salts and borate components of the brine. The insoluble solid particles are filtered out and the liquor is cooled rapidly in continuous vacuum crystallizers under controlled conditions of temperatures and concentrations to crystallize KCl. Cystallization of borax along with KCl from the concentrated liquor must not occur at this stage. KCl is separated from the hquor by filtration. Bicarbonate then is added to the liquor to prevent any formation of sodium... [Pg.117]

In equation 7.1. a 4-chloropyridine was coupled with diethyl(3-pyridyl)borane.3 The reaction was run in aqueous THF in the presence of potassium carbonate. The role of the base is to facilitate the transmetalation step through the formation of a borate ion, as organoboranes are usually not nucleophilic enough to transfer their organic moiety onto the palladium. An alternate function of the base is to increase the electrophilicity of the palladium through exchange of the halide to carbonate. [Pg.138]

The electrical conductivities of soln. of a great many compounds in liquid hydrogen halides have been measured by E. H. Archibald and D. McIntosh. The conductivity is raised considerably by phosphoryl chloride. Sodium sodium sulphide, borate, phosphate, nitrate, thiosulphate, and arsenate chromic anhydride potassium nitrate, hydroxide, chromate, sulphide, bisulphate, and ferro- and ferri- cyanide ammonium fluoride and carbonate j rubidium and caesium chloride magnesium sulphate calcium fluoride ... [Pg.179]


See other pages where Potassium borates carbonate is mentioned: [Pg.276]    [Pg.111]    [Pg.198]    [Pg.77]    [Pg.186]    [Pg.472]    [Pg.478]    [Pg.432]    [Pg.433]    [Pg.227]    [Pg.158]    [Pg.305]    [Pg.174]    [Pg.528]    [Pg.208]    [Pg.223]    [Pg.305]    [Pg.447]    [Pg.112]    [Pg.206]    [Pg.209]    [Pg.134]    [Pg.332]    [Pg.344]    [Pg.423]    [Pg.470]    [Pg.508]    [Pg.745]    [Pg.305]    [Pg.112]    [Pg.183]    [Pg.403]   
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