采用膜分离技术取代当前的蒸发工艺回收植物油浸取工艺中的浸取溶剂,这一新技术不涉及相变,节能效果明显.为此,研制了单壁碳纳米管填充聚二甲基硅氧烷/聚偏氟乙烯(PDMS/PVDF)复合膜,通过接触角和SEM等方法对复合膜的表面进行表征.将制备的复合膜应用于从大豆油/正己烷(质量比1∶3)混合油中回收溶剂正己烷,考察了碳纳米管填充量和高温纯化处理对复合膜分离性能的影响.结果表明,碳纳米管经高温纯化预处理后,所制成填充复合膜的分离性能得到了较大的提高.
Distillation is commonly used for traditional solvent recovery in the extraction step of edible oil processing,which consumes large amounts of energy.As an alternative solvent recovery method,membrane separation process can reduce the energy consumption greatly.In this work,cross-linked polydimethylsiloxane/polyvinylidene fluoride(PDMS/PVDF) composite membranes incorporated of single-wall carbon nanotubes(SWNTs) were prepared,and employed in the recovery of hexane from soybean oil/hexane miscellas(the mass ratio is 1∶3).The SWNTs filled PDMS/PVDF composite membranes were characterized by contact angle meter and SEM.The effects of filling content and thermal pre-treatment of SWNTs on the separation performance were studied.It was found that the separation performances of the SWNTs filled PDMS/PVDF composite membranes were greatly improved with thermal treatment.