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Most of the study on the emulsion liquid membrane (ELM)
separation technologyhas been confined to small batch operation
systems and there has been littleresearch on the continuous
pilot-plant scale test. Investigation of the continuous ELM
separation process on pilot-plant scale is required to develop
the practical application of ELM. In this research, the
extraction and concentraction of phenylalanine using ELM
separation technique in a continuous countercurrent RDC
(Rotating Disc Contactor) column has been newly delveloped.
Noattempt has been made so far to separate phenylalanine by
this process. Due to the zwitterionic character of amino acid,
it is po- ssible to extractand concentrate phenylalanine with a
selective cation-exchange carrier, which is incorporated into
the liquid membrane phase, by controlling the pH of aqueous
solution. In the study, we used D2EHPA and M2EHPA as the
selective carriers, Span80 as a surfactant, kerosene and liquid
paraffinas diluents and hydrochloric acid as the internal
stripping agent. The feasibility of the application of ELM
technique in RDC column separation process to the phenylalanine
extraction was evaluated. The extraction and contraction
efficiency and the leakage and swelling phenomena of ELM at
different operating conditions were discussed. Moreover, the
extraction capability and stability of the fresh ELM and
recycled ELM were also studied and compared. A novel method of
microwave radiation technology was also applied for the
demulsification of the W/O emulsion in the re- search. The
concentrated product was recovered from the emulsion sion and
the membrane phase was reused. Under different opera- ting
conditions of the microwave radiation, the rate of demul-
sification and separation efficiency of different kinds of
emulsions were studied.
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