Preparation method of diammonium hydrogen citrate

Abstract

The invention discloses a preparation method of diammonium hydrogen citrate. The preparation method comprises the following steps: by taking edible citric acid and liquid ammonia as raw materials, dissolving the edible citric acid into water to prepare a 39%-51% solution; introducing liquid ammonia into the citric acid solution, slowly adding liquid ammonia, and controlling the pH value of the solution to be within 4.5-5.5; performing air cooling on the materials to room temperature until a great amount of diammonium hydrogen citrate is crystalized and separated out, and separating mother liquor through a centrifugal machine to obtain diammonium hydrogen citrate crystals; conveying the diammonium hydrogen citrate crystals to a drying oven at 62DEG C-70DEG C, and drying for 45-60 minutes, to obtain diammonium hydrogen citrate; continuously dissolving edible citric acid with the remaining mother liquor and recycling. The high-concentration citric acid is prepared, so that the usage amount of water is less, the citric acid is cooled, crystalized and separated out through the ammonina introduction and reaction, centrifugal is performed, dehydrated mother liquor can be continuously used for dissolving citric acid, and no energy consumption, no emission and no environment pollution exist during the overall process.

Description

technical field [0001] The invention belongs to the field of food additives, in particular to a preparation method of diammonium hydrogen citrate. Background technique [0002] Diammonium hydrogen citrate is a white granule or crystalline powder, soluble in about 1 part of water, the aqueous solution is weakly acidic, slightly soluble in ethanol, and decomposes upon high heat, with a density of 1.48. In addition to the same role as ammonium citrate, it can also be used in probiotics and yogurt starters. The diammonium hydrogen citrate product is usually prepared by reacting citric acid and ammonium salt, and then decolorizing with activated carbon, filtering, removing impurities, concentrating, crystallizing, drying and other processes. This method has a long process, low yield, and exhaust gas emissions , causing environmental pollution. [0003] Among the existing published patents, the patent name is: Synthetic method of ammonium citrate, and the application number is: ...

AI Technical Summary

Problems solved by technology

The diammonium hydrogen citrate product is usually prepared by reacting citric acid and ammonium salt, and then decolorizing with activated carbon, filtering, removing impurities, concentrating, crystallizing, drying and other processes. This method has a long process, low yield, and exhaust gas emissions , causing environmental pollution

[0003] Among the existing published patents, the patent name is: Synthetic method of ammonium citrate, and the application number is: 201110412353.9. The method described in this patent has carried out thermal vacuum concentration of materials, and also added activated carbon to carry out oxidative decolorization and adsorption decolorization , use ammonium sulfide to remove iron and heavy metal ions. The process is cumbersome and complicated, which will affect the output of ammonium citrate. There are many materials to be used, the utilization rate is not high, and the energy consumption is large.

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