Formation and Recovery of Itaconic Acid from Aqueous Solutions of Citraconic Acid and Succinic Acid
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- 作者：Bryan P. Hogle ; Dushyant Shekhawat ; Kirthivasan Nagarajan ; James E. Jackson ; and Dennis J. Miller
- 刊名：Industrial & Engineering Chemistry Research
- 出版年：2002
- 出版时间：May 1, 2002
- 年：2002
- 卷：41
- 期：9
- 页码：2069 - 2073
- 全文大小：51K
- 年卷期：v.41,no.9(May 1, 2002)
- ISSN：1520-5045
文摘
The formation and recovery of itaconic acid (IA) from mixed aqueous solutions of citraconic acid(CA) and succinic acid (SA) has been developed as part of an overall process to produce itaconicacid via condensation of succinates with formaldehyde. The formation and recovery describedhere involves four steps: (1) removal of SA via crystallization, (2) isomerization of CA to IA atelevated temperature, (3) recovery of IA via crystallization, and (4) conversion of reactionbyproducts back to CA. As part of the overall process, these steps facilitate recycling of unreactedspecies and reuse of byproducts, thus giving high overall yields. Itaconic and succinic acids arereadily crystallized because of their low solubility relative to CA; lab-scale crystallizationexperiments gave high purity (99.8 wt % for SA; 99.4% for IA) crystalline solids after washing.Isomerization gave a maximum IA selectivity of 87% at 170 
C after 3 h reaction. The primarybyproduct of isomerization, citramalic acid (CMA), and IA in the residual crystallization liquorare converted exclusively back to CA over 
-alumina at 270 C.
C after 3 h reaction. The primarybyproduct of isomerization, citramalic acid (CMA), and IA in the residual crystallization liquorare converted exclusively back to CA over -alumina at 270 C.