Abstract:

Nano white carbon black particles filled PDMS/PVDF composite membranes were prepared, and FT-IR, TGA and contact angle were used to characterize the physical and chemical characteristics of the composite membranes. By using soybean/hexane miscellas, the separation performance of the composite membranes was systematically investigated. The results indicated that by filling white carbon black to PDMS, the crosslinking density was promoted, and the hydrophobicity, thermal stability and solvent resistance were improved. The permeate flux was declined with increasing filling content of white carbon black, while the oil retention was risen from 96% to 98%. With the increase of oil concentration, both of the permeate flux and oil retention were declined. With increasing feed temperature, the permeate flux was risen while the oil retention was declined. Mass transfer characteristics of soybean oil and hexane through the membrane can be described by the solution-diffusion with imperfections model, and the experimental values of the micelle osmotic pressure were well in accordance with calculated values.

Key words: nanofiltration, membrane, mass transfer, solvent recovery, white carbon black, PDMS

摘要：

将纳米级白炭黑填充于PDMS制备了白炭黑填充PDMS/PVDF复合膜,采用红外(FT-IR)、热失重(TGA)和接触角(CA)等方法对填充复合膜进行了分析和表征,并采用纳滤的方法系统研究了复合膜对大豆油/己烷混合油的分离性能。结果表明,白炭黑填充能有效促进PDMS的交联,提高PDMS的疏水性、热失重温度以及对溶剂的稳定性;白炭黑填充量增加使复合膜渗透通量降低,但截留率从96%提高到98%;随溶液浓度增加,渗透通量和截留率同时降低;随温度的升高,渗透通量上升,截留率降低。大豆油和己烷在膜中的传质特性可用不完全的溶解-扩散模型描述,溶液渗透压实验值与计算值符合较好。

关键词: 纳滤, 膜, 传质, 溶剂回收, 白炭黑, PDMS