Ammonium Fluoride NH

A mixture of 1 part NH Cl and 2V4 parts NaF is gently heated in a platinum crucible. Ammonium fluoride sublimes and is collected on the cooled crucible lid in the form of very small, prismatic, very pure crystals. 

Solid ammonium fluoride cannot be obtained by evaporation of an NH4F solution, since NH3 splits off and NH4HFg is formed. Ammonium fluoride is stored in iron vessels. 

deliquescent, crystalline flakes or needles, very soluble in water decomposes on heating into NI and HF. Attacks glass. Solubility in water at 0°C 100 g./lOO ml. d. 1.015. Structure hexagonal (wurtzite). 

Gaseous ammonia is added to a platinum or lead dish containing hydrofluoric acid imtil the color of Congo paper changes to 

A nickel tube closed at one end serves as the reaction vessel. The tube end projecting out of the furnace is wrapped with a lead cooling coil through which cooling water flows (see Fig. 120). Two 

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The process, as described by Equation (131), is performed at a temperature of about 200-350°C [113]. Vapors of the water formed, ammonia and hydrogen fluoride, are separated from the interaction zone and collected for reuse by condensation at appropriate temperatures in the form of ammonium fluoride, NH F, or ammonium hydrofluoride, NH4HF2. 

Two well-known salts of ammonia (qv) are the normal ammonium fluoride [12125-01 -8] NH F, and ammonium bifluoride [1341 -49-7] NH4HF2 the latter is sometimes named ammonium acid, or hydrogen difluoride. Much of the commercial interest in the ammonium fluorides stems from their chemical reactivity as less ha2ardous substitutes for hydrofluoric acid. 

Manufacture. Anhydrous ammonium bifluoride containing 0.1% H2O and 93% NH4HF2 can be made by dehydrating ammonium fluoride solutions and by thermally decomposing the dry crystals (7). Commercial ammonium bifluoride, which usually contains 1% NH F, is made by gas-phase reaction of one mole of anhydrous ammonia and two moles of anhydrous hydrogen fluoride (8) the melt that forms is flaked on a cooled dmm. The cost of the material in 1992 was 1.48/kg. 

Chemical Designatioiis - Synonyms Acid Ammonium Fluoride, Ammonium Acid Fluoride, Ammonium Hydrogen Fluoride Chemical Formula NH NF. ... 

Chemical Designations - Synonyms Neutral Ammonium Fluoride Chemical Formula NH F. Observable Characteristics - Physical State (as normally shipped) Solid Color White Odor None. Physical and Chemical Properties - Physical State at 15 X and I atm. Solid Molecular Weight 37.04 Boiling Point at I atm. Not pertinent (decomposes) Freezing Point Not pertinent Critical Temperature Not pertinent Critical Pressure Not pertinent ecific Gravity 1.32 at 25°C (solid) Vapor (Gas) Density Not pertinent Ratio of Specific Heats of Vapor (Gas) Not pertinent Latent Heat of Vaporization Not pertinent Heat cf Combustion Not pertinent Heat of Decomposition Not pertinent. 

For complete neutralization to take place, the proper amounts of acid and base must be present. The salt formed in the above reaction is NaCl. If the water were evaporated after completing the reaction, we would be left with common table salt. Sodium chloride is just one of hundreds of salts that form during neutralization reactions. While we commonly think of salt, NaCl, as a seasoning for food, in chemistry a salt is any ionic compound containing a metal cation and a nonmetal anion (excluding hydroxide and oxygen). Some examples of salts that result from neutralization reactions include potassium chloride (KCl), calcium fluoride (CaF ), ammonium nitrate (NH NOj), and sodium acetate (NaC2H302). 

Beryllium fluoride. [CAS 7787-49-7], BeF2, is readily soluble in water, dissolving in its own water of hydration as BeFo 2H2O. The compound cannot be crystallized from solution and is prepared by thermal decomposition of ammonium fluoberyllate. (NH BeF ... 

Typically, the ammonium or hydronium form of the zeolite is slurried in water and reacted with the requisite amount of the ammonium fluoride salt of either iron or titanium. Given the sparingly soluble nature of ammonium fluotitanate, the (NH )2TiF6 can be added to the zeolite slurry in slurry form, or directly as salt. Alternatively, the iron may be added to the zeolite slurry as a slurry of the ammonium fluoride salt crystals in water, or the FeF3 crystals can be mixed with a water solution of ammonium fluoride or ammonium bifluoride, such that the composition of the treatment solution contains the stoichiometry of the ammonium iron fluoride salt, (NH4)3FeF6. The (NH )3FeF6 crystals can also be added directly to the zeolite slurry. The amount of either metal ammonium fluoride salt added during the reaction is determined by the desired product composition and the anticipated completeness of the reaction. 

Preferred conditions for the reaction of the zeolite with the metal ammonium fluoride are as follows. A zeolite-water slurry containing about 10-25 gm of zeolite per 100 cm3 of water is preheated to 75-95°C. When substituting Ti, the titanium salt is added to the zeolite as a water slurry containing finely divided crystals, 10 gm of (NH4>2T1F6 per 100 cm3 of water. With iron substitution, the iron salt, when added as (NH4>3FeF6, is added from a 10 wt.% solution of the salt in water. Alternatively, FeF3 can be added to a solution of NH4HF2 or NH F such that the stoichiometry of fluorine (F2) to Fe3+ is 3.0 and the total amount of salt in solution is about 10 wt.%. The addition rate of the metal ammonium fluoride salt to the zeolite slurry is about 0.005 moles of the metal ion per minute per mole of aluminum in the zeolite. 

Ammonium Fluoride or Malt Salt, NH.4F, mw 37.04, wh poisonous crysts sp gr 1.31, mp — decomp by heat w/o melting sol in cold w. Prepd by interaction of Amm hydroxide with HF, followed by crystn. Used in glass etching, textile mordant, wood preservation and in analytical chemistry (Refs 1 2)... 

In the conditions of SHS-Az technology it is impossible to use ammonium fluoride as hahde salt. And, first of all, on mixing initial components in the presence of NH F, the mixture almost at once begins to warm up, the sohd-phase undesirable reactions take place already during mixing. Sometimes temperature of an initial mixture, depending on a chemical nature of initial components, can increase so, that it will result in its spontaneous ignition. 

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