Downstream processing of biobased succinic acid (3)

Approach III: Ammonium-Based SA Purification: Extraction and Crystallization
(Huh, et al. Process Bio. 41(2006)1461-1465

•Key points for the process
–SA crystallizer: Succinate ion is protonated by ammonium bisulfate to form ammonium sulfate and SA. SA crystallizes due to its low solubility at pH 1.5-1.8 (optimal yield generated)
–Methanol purification: SA is advantageously dissolved in methanol but sulfates relatively insoluble in methanol
–Thermal craker: Ammonium sulfate cracks to produce ammonium and ammonium bisulfate, which can be reused.

•Advantages
–Minimal use of additional reagents
–Produce virtually no waste by-products
–Permit internal recycle of the base and acid

It is recommended!