Scale-up on a Pilot SFC Unit

Analytical SFC units are perfectly suited for optimizing the chromatographic conditions to maximize the process throughput. The separation of TSO racemate developed on an analytical system was therefore successfully extrapolated to a pilot unit equipped with a 50-mm id DAC column (System Supersep 50, Novasep) and integrating a CO2 recycling loop. 

A better resolution of the peaks was observed on the preparative system than on the analytical system. Thus, using a shorter colurrm, cycle time was reduced and injected volume was increased. This small discrepancy can be explained by the fact that analytical systems are controlled by volume flow rates while preparative systems are controlled by mass flow rates. Thus the co-solvent composition and column internal velocity can be slightly different. Table 12.1 shows the scaled-up operating parameters. 

Experimental results for this separation are listed below  

Product concentration of about 12gLstarting from feed containing 16gL of each enantiomer (dilution factor is only 1.33) 

Synthetic pathways (as of 1990-1995) Salt Crystallization (Initial synthetic route) Chromatographic resolution Synthesis from a chiral pool 

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