Ammonium Citrate

Iron(III) ammonium citrate [1185-57-5] is of indefinite stoichiometry. A brown hydrated compound [1332-98-5] of iron(III) ammonium citrate contains 16.5—18.5% iron, - 9% ammonia, and 65% citric acid. A green hydrated compound [1333-00-2] contains 14.5—16% iron, 1% ammonia, and 75% citric acid. Iron ammonium citrates are water soluble but are insoluble in alcohol. The compounds are used to fortify bread, milk, and other foods (see... 

Diammonium citrate [3012-65-5] (NH 2C6H Oy, mol wt 226.19, is soluble in an equal weight of water, but is only slightly soluble in ethanol. The pH of a 0.1 M solution is 4.3. It is made by neutralization of citric acid with ammonia the crystalline or granular product is used as a chemical reagent and pharmaceutically as a diuretic. The price of ammonium citrate in June 1991 was 8.16/kg in dmms. 

Water-soluble crystal modifiers such as yellow pmssiate of soda (YPS) (sodium ferrocyanide decahydrate) or ferric ammonium citrate may also be added to some types of salt as anticaking agents. Both are approved by the U.S. Food and Dmg Administration for use in food-grade salt. YPS and Pmssian Blue (ferric ferrocyanide), are most commonly added to rock salt used for wintertime highway deicing. Concentrations of YPS and Pmssian Blue in deicing salt vary, typically in the range of 20—100 ppm. 

Medical Uses. Citric acid and citrate salts are used to buffer a wide range of pharmaceuticals at their optimum pH for stabiUty and effectiveness (65—74). Effervescent formulations use citric acid and bicarbonate to provide rapid dissolution of active ingredients and improve palatabiUty. Citrates are used to chelate trace metal ions, preventing degradation of ingredients. Citrates are used to prevent the coagulation of both human and animal blood in plasma and blood fractionation. Calcium and ferric ammonium citrates are used in mineral supplements. 

G. W. Bradley and co-workers, "Investigation of Ammonium Citrate Cleaning Solvents," Proceedings of the 36th International Water Conference, Pittsburgh, Pa., Nov. 4—6, 1975. 

Ferric ammonium citrate [1185-57-5]—A mixture of complex chelates prepared by the iateraction of ferric hydroxide with citric acid ia the presence of ammonia. The chelates occur ia brown and green forms, are dehquescent ia air, and are reducible by light. 

AtWONIUM FERRIC CITRATE see FERRIC AMMONIUM CITRATE ... 

Chemical Designations - Synonyms Ammonium ferric citrate, Ferric ammonium citrate (brown), Ferric ammonium citrate (green) Chemical Formula Mixture of FeC HjOy, (NiyjHCjjHjOy, and water of hydration. 

AMMO 2.5 EC , cypermetlu-in, 13 Ammonia, 13 Ammonium acetate, 13 Ammonium arsenate, 13 Ammonium benzoate, 13 Ammonium bicarbonate, 13 Ammonium bifluoride, 14 Ammonium bisulfite, 14 Ammonium carbamate, 14 Ammonium carbonate, 14 Ammonium chloride, 14 Ammonium chlorplatmate, 14 Ammonium clu omate, 14 Ammonium citrate, 14 Ammonium diclu omate, 14 Ammonium fluoride, 14 Ammonium fomiate, 15 Ammonium hexafluorosilicate, 15 Ammonium hydroxide, 15 Ammonium metavanadate, 15 Ammonium molybdate, 15 Ammonium nitrate, 15 Ammonium oxalate, 15 Ammonium perfluorooctanoate, 15 Ammonium persulfate, 15 Ammonium phosphate, 15 Ammonium picrate, 16 Ammonium salicylate, 16... 

Ammonium acetate Ammonium adipate Ammonium benzoate Ammonium bicarbonate Ammonium biflluoride Ammonium binoxalate Ammonium bisulfate Ammonium bitartrate Ammonium tetraborate Ammonium bromide Ammonium carbonate Ammonium chloride Ammonium citrate Ammonium diclnomate Ammonium fluoride Ammonium fluorosilicate Ammonium gluconate Ammonium iodide Ammonium molybdate Ammonium nitrate Ammonium oxalate Ammonium perchlorate Ammonium picrate Ammonium polysulfide Ammonium salicylate Ammonium stearate Ammonium sulfate Ammonium sulfide (hydrosulfide) Ammonium tartrate Ammonium tliiocyanate Ammonium thiosulfate... 

Ammonium citrate. Dissolve 50 g tri-ammonium citrate in 50 mL of concentrated ammonia solution added with care. Cool, and make up to 100 mL with de-ionised water. 

Add cautiously (FUME CUPBOARD), and with constant stirring, 10 mL of the ammonium citrate solution this will prevent the precipitation of metals when, at a later stage, the pH value of the solution is increased. Then add 10 mL of the 20 percent ascorbic acid, and adjust to pH 4(BDH narrow-range indicator paper), by the cautious addition of concentrated ammonia solution down the side of the beaker while stirring continuously. Then add lOmL of the 50 per cent potassium cyanide solution (CAUTION ) and immediately adjust to a PH of 9-10 (BDH indicator paper) by the addition of concentrated ammonia solution. 

Many of these salts melt or sublime before or during decomposition and reaction temperatures generally increase with molar mass. Thermal analyses for a selection of ammonium carboxylates have been given by Erdey et al. [915] who conclude that the base strength of the anion increases with temperature until it reaches that of NH3. Decompositions of ammonium acetate (>333 K) and ammonium oxalate (>473 K) proceed through amide formation. Ammonium benzoate and ammonium salicylate sublime (>373 K) without decomposition but ammonium citrate decomposes (>423 K) to yield some residual carbon. 

Other anticaking ingredients include ferric ammonium citrate, silicon dioxide, sodium ferrocyanide, magnesium silicate, magnesium carbonate, propylene glycol, aluminum calcium silicate, sodium aluminosilicate (also called sodium silicoaluminate), and calcium phosphate. 

According to a Macherey-Nagel application note [35], a mixture of 20 ng each of (i)-cysteine, (L)-glutathione, and (L)-penicillamine was resolved in less than 12 min by HPLC. The method used a Nucleosil 100-5SA column (15 cm x 4.6 mm i.d.) with aqueous 4.5 g/L ammonium citrate-6 g/L phosphoric acid at pH 2.2 as the mobile phase (eluted at 1 mL/min) and electrochemical detection at a gold electrode polarized at +800 mV. 

Dissolve the sample in NaOH solution and precipitate ZnS with NaS solution. Dissolve ZnS in HC1 solution, add ammonium citrate to mask A1 and then titrate Zn at pH = 9 using eriochrome black T as indicator. 

Ammonium citrate, 2 713 molecular formula, 6 638t Ammonium compounds, 2 711-761. 

Ferric ammonium citrate molecular formula, 6 6381 solubility in water, 6 649t Ferric ammonium ferrocyanide pigment used in makeups, 7 836t Ferric bromide, physical properties of,... 

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