PDMS渗透汽化膜改性及其渗透汽化性能研究

发布时间：2018-06-17 14:21

  本文选题：PDMS + 复合膜　； 参考：《长春工业大学》2016年硕士论文

【摘要】：渗透汽化技术是膜分离技术一个重要组成部分,近些年来逐渐成为一种新型的分离技术。安全、高效、分离过程中不引入其他污染物质是渗透汽化技术最鲜明的特点,因此该技术成为了21世纪最有发展前景的膜技术之一。本文先以氢氟酸为表面处理剂对硅橡胶(PDMS)膜进行表面刻蚀改性,增加膜表面粗糙度。刻蚀后的PDMS复合膜采用DSC、FT-IR、SEM及水接触角对其刻蚀后的热稳定性、表面形貌及疏水性进行表征分析;研究了分离乙醇/水体系时操作条件(体系中浓度、温度及渗透压力)对PDMS刻蚀膜分离性能的影响。然后以纳米聚四氟乙烯(n-PTFE)PDMS,经表面淋洗制备了水砂石型PDMS复合膜。运用SEM、DSC、FT-IR、XRD等表征方法研究填充后PDMS膜的热稳定性、形貌以及结构。采用质量比为1:10的n-PTFE-PDMS填充膜对常见制膜废水三元体系(DMAC、氯仿水溶液)进行了分离,通过改变料液温度、浓度以及流速对填充膜渗透汽化性能的影响进行了研究。最后通过添加羟基硅油改性的疏水性纳米白炭黑(SiO_2),制备纳米白炭黑改性PDMS复合膜。硅油羟基可与SiO_2表面羟基缩合,从而实现疏水改性,以正庚烷为有机溶剂,油浴加热控制温度98℃,反应时间50 min,此时白炭黑得到较好改性效果。随后,制备了改性疏水纳米SiO_2填充PDMS复合膜。通过膜中白炭黑含量、料液温度、乙醇浓度和流速的改变,对纳米SiO_2填充PDMS膜分离性能进行研究。
[Abstract]:Pervaporation technology is an important part of membrane separation technology and has gradually become a new separation technology in recent years. Safety, high efficiency and non-introduction of other pollutants in the separation process are the most distinctive characteristics of pervaporation technology, so this technology has become one of the most promising membrane technologies in the 21st century. In this paper, hydrofluoric acid was used as surface treatment agent to etch the surface of silicone rubber (PDMS) film to increase the surface roughness. The thermal stability, surface morphology and hydrophobicity of the etched PDMS composite film were characterized by DSC-FT-IR SEM and water contact angle. Effect of temperature and osmotic pressure on the separation performance of PDMS etched film. Then the water-sand PDMS composite membrane was prepared by surface elution with nano-PTFE PDMS. The thermal stability, morphology and structure of the filled PDMS films were investigated by means of SEM DSCFT-IR XRD. DMAC- (chloroform aqueous solution), a ternary system of membrane wastewater, was separated by n-PTFE-PDMS filled membrane with 1:10 mass ratio. The effects of temperature, concentration and flow rate on the pervaporation performance of the membrane were studied. Finally, the hydrophobic nano-silica modified PDMS composite film was prepared by adding hydrophobic silica modified with hydrophobic silica. Hydrophobic modification was achieved by condensation of silicone oil hydroxyl groups with SiO-2 surface hydroxyl groups. When n-heptane was used as organic solvent, oil bath heating temperature was 98 鈩，

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