Maleic Acid → Ammonium Aspartate

Participants

Reaction Conditions

Reaction Steps

According to the same procedure of Example 1, cells of Alcaligenes faecalis ATCC 8750 was added to 2 L of an ammonium maleate substrate solution containing 400 g of maleic acid, and the substrate solution was gently stirred at 30° C. for 24 hours. After the reaction, ammonium L-aspartate was formed with a molar yield of 99.0% based on maleic acid. To the reaction solution from which the cells had been removed by centrifugation, was added 410 g of maleic acid at 30° C., to precipitate crystals of L-aspartic acid. After the addition, a temperature of the solution was 34.5° C., and pH value thereof was 3.8. L-aspartic acid crystals were separated by filtration, so as to recover 1.6 L of mother liquors. The crude crystals was 502 g (Excluding water) (89.1 wt % aspartic acid, 10.2 wt % malic acid, 250 μm average crystal size). The crystals were washed with 300 ml of water and dried so as to obtain 447 g of L-aspartic acid crystals (99.0 wt % aspartic acid, 0.62 wt % maleic acid, 100 μm average crystal size).

Provenance & Evidence