Partial-discard strategy for obtaining high purity products using simulated moving bed chromatography.

Department of Chemical Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, South Korea.
Journal of Chromatography A (Impact Factor: 4.61). 08/2006; 1122(1-2):161-73. DOI: 10.1016/j.chroma.2006.04.040
Source: PubMed

ABSTRACT A new "partial-discard" operation strategy was developed to improve the performance, especially purity, achievable in simulated moving bed (SMB) chromatography. This strategy was applied to the four-zone SMB process with two columns per zone for binary separation within the linear range. The "partial-discard" strategy significantly enhanced the purity or enrichment when the discard time and discard length were controlled. In addition, the "partial-feed with partial-discard" strategy improved remarkably the extract and raffinate purities at an intermediate feed time compared with the "partial-feed" operation. Adjustments of the discard length and discard time played key roles in achieving the desired product purity in SMB chromatographic performance.

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