Ammonium citrate solution

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. 

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. 

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. 

Theory In ferric ammonium citrate it is taken for granted that the entire iron is oxidized to the Fe2+ state and practically little Fe2+ is present. Thus, the ferric ion present in a known amount of the sample liberates an equivalent amount of iodine from an acidified KI solution. Thus, we have ... 

Materials Required Ferric ammonium citrate 0.5 g sulphuric acid cone. 1 ml 0.1 N KMn04 solution 50 ml hydrochloric acid 15 ml potassium iodide 2.0 g 0.1 N sodium thiosulphate. 

Procedure Weigh accurately about 0.5 g of ferric ammonium citrate and dissolve the sample in 15 ml DW. Add to it slowly 1 ml of sulphuric acid and warm gently to attain a yellow colouration so as to decompose the iron and ammonium citrate complex completely. Cool and add 0.1 N potassium permanganate solution dropwise from a burette to obtain a pink colour that persists for 5 seconds. To the resulting solution add hydrochloric acid 15 ml and potassium iodide 2.0 g, shake well and set aside for 3 minutes so that iodine may be liberated completely. Now, add 60 ml of water and titrate with 0.1 N sodium thiosulphate solution while shaking the contents continuously till a colourless end-point is achieved. 

The methods of analysis for phosphate solubility are not absolute, but empirical that is, they are based on practical experience. For example, the neutral ammonium citrate method is favoured in the USA because it has received over 100 years of study and experimentation, and provides an index correlating the laboratory results with the fertilizing value of water-insoluble phosphates under the conditions prevailing in the principal farming regions of the country. The particular solvent is therefore not an attempt to accurately reproduce the properties of the soil solution in the immediate vicinity of the... 

Einsteinium isotopes are separated on an ion exchange column and eluted with a solution of ammonium citrate. Radioactive isotopes are identified by an activity detector. 

Radium in hydrochloric acid solution may be separated effectively by ion exchange methods using cation exchange-resin columns. A weak HCl solution is passed through the column. The absorbed metals on the ion-exchange column are eluted with ethylenediaminetetraacetic acid (EDTA) at pH 6.25 or with ammonium citrate at pH 7.8. With either eluant, radium is eluted last, after removing barium and then lanthanum, calcium, magnesium, and other metals. 

However, in order to remain reasonable, a more effective eluting agent, such as the solution of 0.1% ammonium citrate at pH 5.0 - 8.0 which gives thejhn (Cit) ]" species had to be used. This system was utilized to separate kilogram quantities of rare earths with a purity better than 99.99% but because of its low total capacity it was commercially unattractive. 

Synonym Ammonia Water Amfbnioformaldehyde Ammonium Acetate Ammonium Acid Fluoride Ammonium Amidosulfonate Ammonium Amidosulphate Ammonium Benzoate Ammonium Bicarbonate Ammonium Bichromate Ammonium Bifluoride Ammonium Carbonate Ammonium Chloride Ammonium Citrate Ammonium Citrate, Dibasic Ammonium Decaborate Octahydrate Ammonium Dichromate Ammonium Disulfate-Nickelate (II) Ammonium Ferric Citrate Ammonium Ferric Oxalate Trihydrate Ammonium Ferrous Sulfate Ammonium Fluoride Ammonium Fluosilicate Ammonium Formate Ammonium Gluconate Ammonium Hydrogen Carbonate Ammonium Hydrogen Fluoride Ammonium Hydrogen Sulfide Solution Ammonium Hydroxide Ammonium Hypo Ammonium Hyposulfite Ammonium Iodide Ammonium Iron Sulfate Ammonium Lactate Ammonium Lactate Syrup Ammonium Lauryl Sulfate Ammonium Molybdate Ammonium Muriate Ammonium Nickel Sulfate Ammonium Nitrate Ammonium Nitrate-Urea Solution Ammonium Oleate... 

Dilute 25 cc. of the ammonium citrate solution with water to 250 cc. To 25 cc. of this diluted solution add 3 gm. of calcined magnesia and about 200 cc. of water, and distil, using a receiver containing 40 cc. of semi-normal sulphuric acid. After the distillation titrate the excess of acid with... 

Uses In iron-toning solutions. Fresh ferric ammonium citrate tends to form a layer of mold after a few days. This can be filtered or lifted off. After the first time the mold rarely returns. Notes Both brown and green salts are light-sensitive. Keep well closed and protected from light. 

Distilled water at 125F/52C, 500.0ml Ferric ammonium citrate, 8.0g Potassium ferricyanide, 8.0 g Acetic acid, 28% solution, 265.0ml Distilled water to make 1.0 liter... 

Dissolve the ingredients separately in water. Mix the ferric ammonium citrate solution and the tartaric acid solution then add the silver nitrate solution while stirring with a nonmetal rod. Add water to make up the complete quantity. Keep in a brown glass bottle, away from light. 

Recently, Chojnacka et al (2005) have reported an excellent linear relationship between available PTMs (As, Cd, Cr, Cu, Hg, Mn, Pb and Zn) content in polluted industrial soils, as extracted by 2% (w/v) ammonium citrate solution, and wheat plants content. For some elements of environmental concern, such as Pb, As, Cd, Hg and Cr, also the results obtained by 0.1 M NaN03, 0.5 M KN03 and 0.05 M CaCl2... 

Figure 3. The inhibition of E. coli around wells charged with human serum or Tr and the neutralization of microbiostasis on serum medium around wells charged with a solution of ferric ammonium citrate (20 i g iron/well) or spent medium at 15-, 25-, and 35-hr incubation period (25)...

A commercial fertilizer is a material that contains at least one of the plant nutrients in chemical form that, when applied to the soil, is soluble in the soil solution phase and assimilable or available by plant roots. Most often, this implies chemical forms that are water soluble. However, in the case of phosphorus, solubility in special reagent solutions (citric acid, neutral ammonium citrate, or alkaline ammonium citrate) often is used as a guide for availability to plants. In the case of nitrogen, slow solubility in water may be more desirable from an environmental and efficiency standpoint than easy solubility. 

A similar ore occurs in the upper stratum ( C-grade ) of the phosphate deposit on Christmas Island. The C-grade ore contains about 25 percent P205 dry basis. Calcination is carried out in a fluidized bed, operated in the range of 400-600°C. The maximum solubility in alkaline ammonium citrate solution is about 70 percent. 

A typical product contains 28-30 percent P205, nearly all soluble in neutral or alkaline ammonium citrate solution. The product is applied in a powdered form or granulated with potash salts. Some grades are produced containing magnesium or boron, which are added during granulation as kieserite or borax, respectively. 

Ferric Ammonium Citrate, Brown, occurs as thin, transparent brown, red-brown, or garnet red scales or granules, or as a brown-yellow powder. It is a complex salt of undetermined structure, composed of iron, ammonia, and citric acid. It is very soluble in water, but is insoluble in alcohol. The pH of a 1 20 aqueous solution is about 5.0 to 8.0. It is deliquescent in air and is affected by light. 

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