Effective separation of succinic acid by combined crystallization

Abstract

Succinic acid, which is widely used as a building block chemical, can be produced from either petroleum or renewable resources. Bio-based production of succinic acid requires several purification steps, and the yield of any particular separation method is an important factor in facilitating an economic design. Crystallization is a common method for the purification of succinic acid, and several driving forces can be used to generate solubility changes in the solution. In this work, three driving forces of crystallization - cooling, acidification, and salting out - were examined individually and combined to achieve maximum yield from a solution of succinic acid. It was found that combined crystallization can significantly improve the yield (97.08%) compared with conventional cooling crystallization (84.31%) or acidification (66-67%). Additionally, a basic kinetic study was performed, and a total of 7 minutes of batch operation was sufficient to produce the maximum amount of crystals.