Recovery of fumaric acid by membrane crystallization in the prouction of L-malic acid

摘要

A study on redesigning traditional crytallizers by using microporous hydrophobic membranes and, in particular, the realization of a separation unit aiming to recover the unreacted fumaric acid leaving a biocatalytic membrane reactor for the production of L-malic acid is presented. The development of two main conceptual aspects of this operation are analysed: oneconcerning the transport of matter and energy through membrane, other, the physical and chemcal phenomena that occur during crystalization. From experimentally determined particle size distributions and induction time meaurements, the parameters of a set of equations describing both heterogeneous and secondary nucleation processes, as well as growth rate, have been evaluated. Finally, prpulation balance equation has been applied in order to predict the evolution of CDS in time.