Practical Application Separation of Sugars

Note that this example is built as a pedagogical example. The results given in the following are not all experimentally obtained, but are very typical of what is obtained with sugars. The methodology proposed enables us to get a precise understanding of the method that makes it possible to calculate an SMB. If a very precise design is required, however, some simple hypothesis should be relaxed and more sophisticated model used. 

The problem consists in performing the separation of a monosaccharide (mono) and a disaccharide (di). A preliminary screening has shown that these sugars can be separated on a cationic ion-exchange resin (250 ju.m) in calcium form Ca using water (65°C) as eluent. The problem is to design a 

FIGURE 12 Separation of the isomers of threonine. Internal profiles obtained on a LICOSEP 12-26 (NOVA SEP). 

SMB able to process a flow rate of 50 liters/hr of a solution containing 100 g per liter of each sugar. Each stream (extract and raffinate) should contain products at a minimum purity of 97%. 

All the tests were performed on a column of 75 X 1 cm (the laboratory column) packed with the cation-exchange resin to be used in the SMB the temperature is fixed to 65°C. A small injection (Vini = 0.5 mL) of a mixture containing 10 g per liter of monosaccharides and 10 g per liter of disaccharides is performed on the laboratory column eluted by a flow rate of 5 mL/min of water. The retention times of the peaks are tR mono) = 5.7 min and tR(di) = 7.54 min. 

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