Alkali nitrate/nitrite

It is unusual in being flammable with so high a chlorine content (70%), and mixtures with air may detonate if confined when ignited. One case of spontaneous ignition under ambient conditions was observed [1], It has an unusually low autoignition temperature (43 3°C). A survey of hazards and combustion is found in [2], There is a risk of combustion with fluorochloromethanes. Autoignition was observed on contact with traces of a mixture of alkali nitrates/nitrite. 

When mixtures of anhydrous cobalt or manganous sulfate with alkali nitrates, nitrites, halogenates or perchlorates are heated, they turn brown or black because of the production of higher cobalt or manganese oxides. In these cases, the fused nitrates etc. function as oxygen donors to the solid sulfate ... 

Recent Progress in Alkali Nitrate/Nitrite Developments for Solar Thermal Power... 

State of the art Alkali Nitrate/Nitrite salt mixtures... 

Table 73.1 Overview of alkali nitrate/nitrite salt systems for CSP. Common cation systems are usually not considered...

State of the art alkali nitrate/nitrite mixtures 2 Single salt NaNOj 306 °C KNO3 334 °C... 

Novel alkali nitrate/nitrite mixtures 5 Quaternary additive, common anion quaternary reciprocal Ca(N03)2-KN03-LiN03-NaN03 105 °C Li, Na, K//NO2, N03 80°C... 

Heating with the following solids, their fusions, or vapours (a) oxides, peroxides, hydroxides, nitrates, nitrites, sulphides, cyanides, hexacyano-ferrate(III), and hexacyanoferrate(II) of the alkali and alkaline-earth metals (except oxides and hydroxides of calcium and strontium) (b) molten lead, silver, copper, zinc, bismuth, tin, or gold, or mixtures which form these metals upon reduction (c) phosphorus, arsenic, antimony, or silicon, or mixtures which form these elements upon reduction, particularly phosphates, arsenates,... 

Nitrites are the salts of nitrous acid, discovered by Scheele in 1774. The inorganic nitrites, with die general formula M.N02, where M is a metal, are well known. They are all insol in w with the exception of the alkali nitrites. Nitrites may be prepd either by thermal decompn of alkali nitrates 2KN03 2KNOJ + 02 or by reduction of nitrates by C or Pb 2KN03 + C 2KN02 + C02. The lone pair of electrons in the nitrite ion is sterically significant consequently, the nitrite ion is bent ... 

Copper(II) sulfate Cumene hydroperoxide Cyanides Cyclohexanol Cyclohexanone Decaborane-14 Diazomethane 1,1-Dichloroethylene Dimethylformamide Hydroxylamine, magnesium Acids (inorganic or organic) Acids, water or steam, fluorine, magnesium, nitric acid and nitrates, nitrites Oxidants Hydrogen peroxide, nitric acid Dimethyl sulfoxide, ethers, halocarbons Alkali metals, calcium sulfate Air, chlorotrifluoroethylene, ozone, perchloryl fluoride Halocarbons, inorganic and organic nitrates, bromine, chromium(VI) oxide, aluminum trimethyl, phosphorus trioxide... 

The purification of the alkali hydroxides.—Numerous impurities have been reported in commercial sodium and potassium hydroxides. Several have commented on the presence of peroxide, particularly in caustic potash.19 Various salts—carbonate, sulphate, nitrate, nitrite, chloride, and phosphate—as well as alumina, silica, organic matters, and metal oxides—e.g. arsenic, vanadium, iron, etc., have been reported. More or less of the other alkalies may also be present. 

Nitrotoluenes, Van No strand, NY(1918) 2)M.Kostevitch, "Tarry Matter of Alpha Trinitrotoluene, Part II, Imprd Art Vol-taire,P aris( 1927), 8 3)Sidgwick( 19 37), 259 et seq 4)Davis(1943), 136-7, 147, 149-51 170-1 5>negering( 1950), 139 seq 6) Dept of the Army TM 9-1910( 1955), 146 Alkalies, Action on Nitric Esters. Organic nitrates in general are readily saponified by alkaline solns. A simple metathetical reaction to yield the alkali nitrate and alcohol does not take place instead, as a result of simultaneous oxidation and reduction, alkali nitrite and a variety of products are formed depending on the conditions of the reaction. The resistance of different nitric esters to alkalies varies considerably. Thus, starch nitrate is decomposed much more slowly than cellulose nitrate and amylopectin nitrate still more alowly... 

In the patent referred to above, the cell described is suitable for the electrolysis of alkali chloride and is of the bell type, but it is particularly suitable for electrolysing alkali nitrate. Pure nitric acid is formed at the anode inside the bell and is removed by distillation, which is effected by working under reduced pressure and by heating the bells with superheated steam. The nitrite which is formed at the cathode is drawn off continuously and separated outside the cell. The cell itself acts as cathode, and the anode is of such size as to almost dll the bell and thus reduce the working space of the eleotrolyte. High current density (16 amps, per dm.8), reduced pressure and high temperature, are favourable to the distillation of a large amount of concentrated nitric acid. 

Alkali nitrates, when healed above their melting-points, yield the corresponding nitrite and oxygen but the gas is contaminated with nitrogen resulting from partial decomposition of the nit rite. In the ease of potassium nitrate the reaction may be represented by the equation ... 

The decomposition of alkali nitrates appears to be a reversible reaction. Whim heated in oxygen at a pressure of 175 atmospheres at a temperature gradually rising from M)5° to 5iMt" C. during nine hours, sodium nitrite is almost completely oxidised to nitrate. Tims ... 

The substance decrepitates. 2. The substance deflagrates. 3. The substance fuses and is absorbed by the charcoal, or forms a liquid bead. 4. The substance is infusible and incandescent, or forms an incrustation upon the charcoal. Crystalline salts, e.g. NaCI, KC1. Nitrates, nitrites, chlorates, perchlorates, iodates, permanganates. Salts of the alkalis and some salts of the alkaline earths. Apply test (ft) below. 

Generally liquid ammonia is a good solvent for many salts, such as nitrates, nitrites, iodides, cyanides, thiocyanides, and acetates. Ammonium salts are especially soluble. The hydroxides, fluorides, and salts with di- and trivalent anions, such as oxides and sulfides, in general are insoluble. Apart from alkali metals, some other metals and nonmetals are also soluble. A compilation of the solubilities of organic compounds in liquid ammonia shows notable solubility of saccharoses [1417],... 

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