Abstract:
Lactic acid is a naturally occurring organic acid that can be used in a wide variety of industries, such as the cosmetic, pharmaceutical, chemical, food, and, most recently, the medical industries. It can be made by the fermentation of sugars obtained from renewable resources, which means that it is an eco-friendly product that has attracted a lot of attention in recent years.Keywords: Lactic acid; Fermentation; Renewable resources; Separation processes
LACTIC ACID PROPERTIES:
| Properties | Values |
| Density at 20ºC(g/L) | 1.249 |
| Melting point (ºC) | 52.8 (D): 53.0 (L): 16.8 DL) |
| Boiling point(ºC) | 82.0(DL)a 0.5 mm Hg:122.0 (DL) at 15 mmHg; 103 (D) at 15mmHg |
| Dissociation constant (pKa) at 25ºC | 3.83 (D);3.79 (L) |
| Heat capacity (J/m olºC) at 20ºC | 190 (DL) |
| Heat of solution (kJ/m ol) at 25ºC | 7.79 (L) |
| Heat of fusion (kJ/m ol) | 16.86 (L);11.33 (DL) |
APPLICATIONS:
Lactic acid has a wide range of applications in chemicals, pharmaceuticals, and food, and it is a precursor to several products. The uses and demand of lactic acid are shown in Fig. 1. Although commercially available long ago, it is only in recent decades that new uses have resulted in a great increase in the demand.
SEPARATION AND PURIFICATION PROCESSES:
Separation processes are essential to the chemical industry and other related industries. Approximately 40% to 70% of operating and capital costs are associated with the separations steps (Wankat 2007). In lactic acid production processes, development of an effective method of lactic acid separation and purification from fermentation broth is extremely important for economic viability. Although the difference between the boiling point of lactic acid and water is relatively large, it is almost impossible to obtain pure crystalline lactic acid. This is because lactic acid has a high affinity for water and a dimer of lactate is formed when lactic acid concentrations are sufficiently high.
Factory Workshop Presents:
