An improved process for preparing ammonium salts from fumaric or succinic acid, is described. The method consists of neutralizing the corresponding acid carbonate or ammonium bicarbonate at a molar stoichiometric or greater than the stoichiometric ratio of 4-5% in a saturated aqueous solution of the synthesized salt at a temperature not exceeding 40° C., followed by separation of the product and drying at a temperature not exceeding 70° C. After separation of the ammonium salts, the filtrate can be re-used. Isolation of the product is usually carried out by cooling the reaction mixture to a temperature of 15-18C°.
The product comes out in almost crystalline form. Saturated aqueous solution of the synthesized salt is formed by the interaction of carbonate or ammonium bicarbonate with the appropriate acid at a temperature not exceeding 40° C. It is possible to obtain cleaner salt concentration weighing more than 99% and not yielding lower than 98%. The method allows for an increase in the yield of targeted products and ensures their consistent high quality due to their formation in crystalline form.
EXAMPLE NO. 1
Synthesis of Di-Ammonium Salt from Succinic Acid(cas:110-15-6) (S4H12N2O4)
The synthesis is carried out in about in the same conditions as in example 3, however, instead of a freshly saturated solution of salt, a recycled (180 L) of filtrate is used, generating 148 kg of ammonium succinate with a content mass of 99.8%. Salt yield is 100%.
EXAMPLE NO. 2
Synthesis of Mono-Ammonium Salt from Succinic Acid(cas:110-15-6) (C4H12N2O4)
Initially, 2 liters of a saturated solution of salt water is prepared by taking 1 liter of water, 0.65 kg (8.23 M) of ammonium bicarbonate and mixing in 0.971 kg (8.23 M) of succinic acid at a temperature of 38 to 40° C. At a temperature of 38° C. 1.157 kg (9.81 M of succinic acid is added to the resulting solution and 0.775 kg (9.81 M) of ammonium bicarbonate is dispensed for one hour then cooled to 16° C. and filtered on a Nutsche filter cake, which is dried at 70° C. The filtrate is then returned for recycling. This yields 1.3 kg of mono-ammonium salt containing a 99.5% mass. The salt yields at 98.5%.
It should also be appreciated that various modifications, adaptations and alternative embodiments thereof may be made within the scope and spirit of the present invention. The invention is further defined by the following claims.
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