| 摘要 |
<p>The present invention relates to a method of producing dipotassium ascorbate-2-sulphate dihydrate, a vitamin C derivative. Among other purposes, it is used as an additive in fish food. Pursuant to the invention, trimethylamine-sulphur trioxide complex is added in only slight molar excess to a concentrated solution of potassium L-ascorbate in water and the pH of this reaction mixture is adjusted in the range between 9.5 and 10.5 by successive additions of potassium hydroxide and maintained at this value for the duration of the reaction. The method permits the economical preparation of dipotassium ascorbate-2-sulphate dihydrate on a commercial scale. Also indicated is how trimethylamine-sulphur trioxide complex can again be recovered from trimethylamine accumulating as by-product during the preparation of the dipotassium ascorbate-2-sulphate.</p> |
