Recovery of petroleum ether from solanesol extracting solution through vacuum hydrophilic membrane distillation

摘要

This work aims to study the feasibility of vacuum membrane distillation by using hydrophilic membranes, and the recovery of petroleum ether from the extracting solution of solanesol was chosen to investigate. Different with the traditional MD process, hydrophilic membranes were used for the non-aqueous solutions to avoid the membrane wetting. The VMD performances of PVDF membrane and two kinds of PAN membranes with different structure were compared for the solanesol extract under the same operation conditions. The results showed that the PAN membranes performed very well for the petroleum ether recovery, while the PVDF, which is a popular VMD membrane material, was not appropriate for the non-aqueous solutions system. The structures of the membranes were compared to explain the different results for the VMD by PAN1 and PAN2 membranes. The effects of different operating parameters using different PAN membranes have been investigated to further verify the feasibility of VMD by using hydrophilic membranes. The results showed that high feed temperatures, low downstream pressures enhanced the permeation flux for both membranes, and the permeation flux of PAN1 decreased more greatly than PAN2 under high concentration. It is advisable to work at the downstream pressure of 20 kPa, the feed temperature of 30 o C and the feed flow rate 27.5 ml/s that preferentially favor vaporization of petroleum ether and less possibility of membrane wetting.