Abstract
A synthesis process has been developed to produce D-pyroglutamic acid (D-PGA) from L-glutamic acid (L-GA) by employing successive racemization of L-GA, resolution of D,L-glutamic acid (D,L-GA) and dehydration of D-glutamic acid (D-GA). Aqueous NaOH solution of pH>13 at 160°C has been selected as the best racemization medium. The system of 140% supersaturation that contains 1 g of seeds at 50°C was further screened as the best condition by use of preferential crystallization. An irreversible first-order kinetics has been employed to simulate the dehydration of D-GA, in which the activation energy of 40.0 kJ/mol was determined. Increasing the temperature results in high dehydration rate with low stereopurity for the desired D-PGA, in which 130°C was selected as the best dehydration temperature.
| Original language | English |
|---|---|
| Pages (from-to) | 177-182 |
| Number of pages | 6 |
| Journal | Journal of the Chinese Institute of Chemical Engineers |
| Volume | 31 |
| Issue number | 2 |
| State | Published - 03 2000 |
| Externally published | Yes |
Keywords
- D-pyroglutamic acid
- Dehydration
- L-glutamic acid
- Preferential crystallization
- Racemization
- Resolution