초록
<P><B>Highlights</B></P><P>► The novel refining process was compared with the existing one. ► Effects of the solvent extraction step on short-path distillation were discussed. ► Multiple-pass distillation also deserved special attention. ► The novel process permitted the reduction of the operating costs.</P> <P><B>Abstract</B></P><P>This paper introduces a novel process for recovery and refining of <SMALL>L</SMALL>-lactic acid from a fermentation broth. The use of a solvent extraction step, in the novel approach, has significant impacts on the following centrifugal short-path distillation conditions (operating pressure, evaporator temperature and feed flow rate). As the conditions were varied, the <SMALL>L</SMALL>-lactic acid purity and yield in the distillate were monitored. For the purpose of comparison, a series of experiments were also carried out using the existing purification process. The results showed that both of the two processes can obtain <SMALL>L</SMALL>-lactic acid with a high purity around 91.3%, while the yield obtained using the novel process reached 61.73%, which was about 20.43% higher than that using the existing process. Additionally, multiple-pass distillation observed special attention by improving the yield up to 74.63%.</P>