Fig. 5: In situ extraction/back extraction using the reconfigurable membrane.

a Schematic illustration of the extraction-back extraction coupling and recycling process. b Digital photographs of the in situ back extraction process based on FS-SSM (i–iii). Real-time concentration of phenol in the back extraction agent phase during c the in situ back extraction process and d the traditional route. e Evaluation to back extraction performances of two methods from three different evaluation perspectives containing back extraction efficiency, volume recovery of the back extraction agent, and separation efficiency. Real-time concentration of phenol in the extraction agent phase during f the in situ extraction process and g the traditional route. h Extraction efficiency and water content in the collected extraction agent of the in situ extraction and traditional methods.