Simulated Moving Bed Equipment Designs

Abstract Simulated Moving Bed or SMB chromatography is a continuous adsorption technique that increases throughput, purity and yield relative to batch chromatography. SMB utilizes a series of columns with periodically moving inlet and outlet ports. This technique has been applied for the production of petrochemicals and sugars, and to a limited extent, pharmaceuticals. The recent surge in SMB research has led to various novel SMB schemes or configurations. This review presents a survey and comparison of SMB schemes and equipment, specifically SMB valve designs, which are needed to implement the various schemes. Illustrated examples include SMBs with three, four, five, eight, nine, or twelve zones, Varicol scheme, Japan Organo process, fast startup and shutdown, and online decoupled regeneration. The SMB valve designs reviewed are classified into central and distributed valves designs, which include two‐way‐valve designs and rotary‐valve designs. We also present a novel SMB design, the Versatile SMB or V‐SMB, which can implement all the novel schemes by using a one‐rotary‐valve‐per‐column design. Select‐Trapping valves are used to interrupt the stream between the columns and to act as a junction that allows streams to be partially or totally added or removed, or to flow through to the next column. The streams can also be redirected to another SMB zone. Compared to other SMB valve designs, the V‐SMB: (1) can be configured for open‐loop, multi‐zone and zone bypass operation; (2) does not require a carousel for column rotation; (3) does not contribute to product contamination; (4) allows independent port switchings, which is required for certain schemes; (5) allows additional columns to be added easily; and, (6) requires only constant speed pumps. The V‐SMB has successfully purified enantiomers, sugars, organic acids, an antibiotic, and biosynthetic human insulin.