Asynchronous switching three-zone-belt simulation moving bed

Abstract

The invention relates to an asynchronous switching three-zone-belt simulation moving bed, which is provided with a constant current pump, a switching valve, a reverse pressure valve, N chromatographic columns, N one-way valves and 2N four-way valves, wherein raw material liquid and eluate are respectively conveyed to a raw material liquid valve and an eluate valve through the constant current pump; each of the raw material liquid valve and the eluate valve is a one-inlet N-outlet switching valve; only one outlet is communicated with the inlet at any moment; the N chromatographic columns are connected in series; the inlet end of each chromatographic column is connected with one four-way valve; the other three openings of the four-way valve are connected with the outlet of the former chromatographic column, the raw material liquid valve and the eluate valve; the outlet of each chromatographic column is also connected with one four-way valve; the other three openings of the four-way valve are connected with the inlet of the next chromatographic column, an extraction liquid valve and a faffinate valve; the extraction liquid valve and the faffinate valve are N-inlet and 1-outlet switching valves; only one inlet is communicated with the outlet at any moment; the outlet of the extraction liquid valve is connected with an extraction liquid constant current pump; the extraction liquid constant current pump is externally connected with the reverse pressure valve, and is then connected with a faffinate collecting bottle; the outlet of the faffinate valve is connected with the faffinate collecting bottle; a one-way valve is arranged between every two adjacent four-way valves.

Description

technical field [0001] The invention belongs to the field of separation engineering, and in particular relates to a three-zone simulated moving bed with asynchronous switching. Background technique [0002] Simulated moving bed (SMB) is a continuous preparative chromatographic separation technology, which simulates the reverse reaction of the stationary phase by switching the eluent inlet, feed inlet, extract outlet, and raffinate outlet along the flow direction of the mobile phase at a specific time. To move to realize the countercurrent operation of solid-liquid two-phase, while avoiding the difficulty of actually moving the stationary phase. This technology was first developed by the UOP company of the United States and was successfully used for the separation of xylene isomers (BROUGHTON DB. Production-scale adsorptive separations of liquid mixtures by simulated moving-bed technology [J]. SepSciTechnol, 1984, 19 (11-12): 723-36). Later, it was successfully used in sugar...

AI Technical Summary

Problems solved by technology

[0004] In the traditional four-zone SMB, in order to circulate the solvent, a pump needs to be added between zone IV and zone I, which increases the dead volume of the system

The three-zone SMB does not contain zone IV and has no solvent circulation. It is an open-loop system. Its advantage is that it reduces the dead volume of the system and avoids cross-contamination. The disadvantage is that the solvent consumption is large.

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