Kontinuierliche Kristallisationskontrolle am Beispiel von Ascorbinsäure

Abstract

A method for continuous monitoring (without sampling) of the crystallisation process was developped for ascorbic acid. The method is based on measuring ultrasound absorption (at 2 - 3 MHz) by an ascorbic acid suspension (satd. aq. soln.) containing a known amount of added ascorbic acid crystals und continuous stirring. The method allows measuring the concentration of crystals at any period of the crystallization process and at different temperature regiments. The results did not differ significantly from those obtained by the traditional gravimetric method.