This is what I have found, although the language is dated, imperial measures and somewhat difficult to understand in places, this is from COOLEY’S CYCLOPÆDIA
OF PRACTICAL RECEIPTS AND COLLATERAL INFORMATION ... 1880
Ferric and Ammonium Citrate. Syn. Ammonio-citrate of iron: Ammonio ferric citrate; Ferri ammonio citras. L. There are several preparations in which the term ‘citrate of iron’ has been applied. That commonly known under this name is really a double citrate of iron and ammonia, and appears to be correctly called ‘ammonio-citrate of iron.’
B. P. Liquor Ferric Persulphatis (B. P.), 8; liquor ammonia, 191⁄2; citric acid (in crystals) 4; distilled water, a sufficiency, mix 14 of the solution of ammonia, with 40 of water, and all gradually; the solution of ferric sulphate stir constantly and briskly; let the mixture stand two hours, and put into a calico filter and allow to drain. Wash well the precipitate until it no longer gives a precipitate with barium chloride. Dissolve the citric acid in 8 oz. of the water, and having applied the heat of a water bath add the precipitate of ferric hydrate previously well drained, stir them together until the whole or nearly the whole of the hydrate has dissolved. Let the solution cool, then add 51⁄2 of the ammonia, filter through flannel, evaporate to the consistency of syrup, and dry it in thin layers on flat porcelain or glass plates at a temperature not exceeding 100°.
Prep. (Ph. L.) Ferrous sulphate, 12 oz.; carbonate of sodium, 121⁄2 oz.; dissolve each separately in boiling distilled water, 6 pints; mix the solutions whilst still hot, and allow the precipitate to subside; after a time decant the supernatant liquor, wash the precipitate frequently with water (drain it), add of citric acid (in powder), 6 oz., and dissolve by the aid of a gentle heat; when the whole has cooled, add of liquor of ammonia, Ph. L., 9 fl. oz., and gently evaporate to the consistence of a syrup; in this state spread it very thinly on flat earthenware dishes (or sheets of glass), dry by a gentle heat, and when dry keep it in well-stoppered bottles.
(Ph. D.) Citric acid, 4 oz.; distilled water, 16 fl. oz.; hydrated ferric oxide, obtained from the sulphate, 5 oz.; liquor of ammonia, 4 fl. oz., or q. s.
(Wholesale.) A mixture of iron filings and citric acid, in powder, with barely sufficient water to cover it, is kept in a warm situation for some days, occasionally stirring the mass, and replacing the water as it evaporates. A saturated solution is next made in distilled water, there being previously added more citric acid (about half the weight of the acid first used), as required; it is then neutralised with liquor of ammonia (about 11⁄4 oz. of liquor of ammonia, sp. gr. ·882, to every gallon of the solution of sp. gr. 1·025), and the solution is concentrated by evaporation; the process is then completed as in No. 1. The first part of this process produces a salt of the protoxide of iron, or ferrous citrate, which is afterwards converted, by exposure to the atmosphere, into a citrate of the magnetic acid, or ferri, ferro-citrate, and, lastly, into citrate of peroxide of iron, or ferric citrate.
B. P. Liquor Ferri Persulphatis 8. Liquor ammoniæ 191⁄2. Citric acid (in crystals) 4. Distilled water, a sufficiency. Mix 14 of the solution of ammonia with 40 of water, and add gradually the solution of ferric sulphate. Stir constantly, let the mixture stand 2 hours and filter through calico, and allow to drain. Wash until the washing ceases to precipitate barium chloride, dissolve the citric acid in 8 of water, add the precipitated ferric hydrate, and heat in a water bath until dissolved. Let the solution cool, add 51⁄2 of the ammonia, filter through flannel, evaporate to the consistency of syrup, and dry on flat porcelain plates in thin layers at a temperature below 100° F.
Obs. Pharmaceutical writers have been so diffuse in their disquisitions on the preparation of this salt, as would lead to the inference that there is some difficulty attending it. The contrary is, however, the case. The only care necessary is to spread the syrup solution very thinly on warm sheets of glass to dry, which it will rapidly do if they are placed in an atmosphere of warm dry air, for which purpose a ‘drying closet’ is the most convenient. The dry salt may then be easily detached from the glass, and will form thin scales, or lamellæ, of great brilliancy and beauty. It is also better to use a little more oxide than the acid will dissolve, as the remainder will be employed in a future operation. Less water may be used, or even a larger quantity than that mentioned; but in the first case the liquid will become difficult to filter—in the latter it will require more evaporation. Boiling water dissolves about twice its weight of citric acid, and there remains 13⁄20ths of this quantity in solution when cold, and it takes rather more than910 twice the weight of the citric acid in moist hydrated protoxide of iron to produce saturation.
Prop., &c. This beautiful salt is of a rich ruby colour, and forms glistening transparent scales, very soluble in aqueous menstrua, and the resulting solution is less easily decomposed by reagents than the solutions of most of the other salts of iron. It is ‘compatible’ with the alkaline of carbonates and bicarbonates, and several other salts, and is nearly tasteless, advantages which have been perhaps overrated by both prescriber and patient. It is doubtful whether this article has not obtained a larger sale from its pleasing appearance than from its medicinal virtues. Several persons who have prepared it in lumps or powder, by the simple evaporation of the solution to dryness, have been unable to sell it under that form, even at a lower price.
Ammonio-citrate of iron is soluble in water; the solution neither changes the colour of litmus nor turmeric; nor is it turned blue by ferrocyanide of potassium; but either potassium hydrate or lime water being added, it throws down ferric hydrate, and ammonia is evolved. From 100 gr. dissolved in water, potassium hydrate precipitates about 34 gr. of ferric hydrate.—Dose, 3 to 10 gr., in water, wine, or bitter infusions.
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Topic: How to make Ferric Citrate (Read 13267 times)