Water → Calcium DL-tartrate

Temperatur

27 °C

D,L-tartaric acid, 44.7 g, 101.05 g of 50% sodium hydroxide, 50 g water, and 1.5 g calcium hydroxide were placed in a 500 ml round bottom flask fitted with a thermometer, condenser, addition funnel and mechanical stirrer. A calcium tartrate filter cake from a previous reaction (133.2 g,50% solids) was added to the reactor. The mixture was stirred at 120 rpm and heated to 80°±2° C. The calcium maleate solution was added and the reaction continued at 88°±2° C. Water, 73 g, was stripped from the reaction mixture with a flowing air stream over the 40 minutes of reaction. The reaction solution clarified after about one hour. Total reaction time was three hours. 250 g of water was added and the mixture cooled slowly while slowly adding acetic acid, 13.8 g over30 minutes. At the end of this time the pH of the mixture had been reduced to 9.13 and the temperature reached 68° C. Then the mixture was slowly cooled over 75 minutes from 68° C. to 35° C. Finally,the mixture was cooled to 27° C. in an ice bath. The mixture was filtered using a fritted glass filter funnel. The filtration took only five minutes and provided 485.5 g of filtrate and 59.1 g of calcium tartrate wet cake. On standing overnight, additional calcium tartrate crystallized out and was filtered off, weight, 17.6 g.

1. customfitted with a thermometer, condenser, addition funnel and mechanical stirrer
2. filtrationA calcium tartrate filter cake
3. customfrom a previous reaction (133.2 g,50% solids)
4. additionwas added to the reactor
5. temperatureheated to 80°±2° C
6. customcontinued at 88°±2° C
7. waitTotal reaction time was three hours
8. customreached 68° C
9. temperatureThen the mixture was slowly cooled over 75 minutes from 68° C. to 35° C
10. filtrationThe mixture was filtered
11. filtrationfilter funnel
12. filtrationThe filtration
13. waittook only five minutes

ORD-Eintrag

ord-59356aca64a042e9be8608b0684e42c0

Quelldatensatz

uspto-grants-1989_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04867901