Succinic Acid → HCID 18624878, compound

A mixture of 2000 g of succinic acid (water-wet, 82.5%) and 400 g of butyrolactone is heated to the boil in a fractionating column having 10 theoretical trays. The rising vapor is removed at a reflux ratio of 3:1 and is condensed. The bottoms temperature is initially 115°C and rises over 4 hours at a constant rate to 170°C. The temperature at the top of the column remains at 100°C during this period and 500 g of water are distilled off. The reflux ratio is now raised to 5:1. After a further hour a total of 560 g of water has distilled off. The temperature of the vapors at the top of the column rises to 200°C and dehydration is complete. The butyrolactone is distilled off at 110°C/35 mm Hg to give 392 g thereof. The vacuum is then increased to 17 mm Hg and an intermediate run of butyrolactone/succinic anhydride gives a total of 54 g distilled off. At a constant boiling temperature of 142°C, 1094 g of succinic anhydride then distil over, this being equivalent to 78% of theory.

1. temperatureis heated to the boil in a fractionating column
2. customThe rising vapor is removed at a reflux ratio of 3:1
3. customcondensed
4. customis initially 115°C
5. waitThe temperature at the top of the column remains at 100°C during this period
6. distillation500 g of water are distilled off
7. temperatureThe reflux ratio is now raised to 5:1
8. distillationAfter a further hour a total of 560 g of water has distilled off
9. customrises to 200°C
10. distillationThe butyrolactone is distilled off at 110°C/35 mm Hg
11. customto give 392 g
12. temperatureThe vacuum is then increased to 17 mm Hg

ORD record

ord-0594665754174db8993aeec0b9a9a136

Source dataset

uspto-grants-1976_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US03957830