Abstract
A small-scale EMR system was developed with a reliable control design giving the possibility for continuous operation at constant flux (constant hydraulic residence time, tHRT). A PID controller was implemented to control the flux during continuous operation. In this study, lactulose yield is shown to depend on the molar ratio of lactose to fructose, mL/mF under batch operation. Specific yield in continuous operation of lactulose synthesis was higher than in batch mode. In batch process, the produced lactulose underwent secondary hydrolysis which led to a rapid reduction of the lactulose concentration. In continuous processes, a shorter tHRT obtained higher specific yield. Nevertheless, it acquired a particular drawback as fouling occurred on top of the membrane and could inevitably influence the operational time span of the membrane. Conclusively, fouling and yield have to concomitantly be taken into consideration for continuous production of lactulose in an EMR system.
