论文总字数：20973字

摘 要

膜分离技术具有分离精度与分离效率高，且环境友好易于集成等优点，在水处理领域具有广阔的应用前景。然而，水处理膜在运行过程中极易被水体系中的颗粒污染，膜表面及孔道内被填充从而导致分离效率下降。膜污染严重限制了膜技术的推广与应用，开发自清洁抗污染膜成为当前膜技术研究重点。压电陶瓷膜是一类有压电材料制备的多孔分离膜，其在分离过程中可以原位产生超声波，从而起到去除污染物堆积，缓解膜污染的效果。基于锆钛酸铅（PZT）制备的压电陶瓷膜已经展现出了良好的抗污染效果与应用前景，但是，在与水直接接触的环境中使用含铅量高达60%的PZT材料存在一定的安全隐患。本研究以无铅压电陶瓷α-石英为主要原料，以Al₂O₃及十二烷基苯磺酸钠（SDBS）为烧结助剂制备无铅压电陶瓷载体。考察了煅烧温度对多孔SiO₂陶瓷性能的影响，实验结果表明，升高煅烧温度可以促进颗粒颈部间反应的进行，强化颈部连接作用并撑开SiO₂颗粒之间的间隙，从而提高陶瓷机械强度及渗透性能。但是当温度达到1300 ^oC及以上时，α-石英转变为α-方石英减弱了多孔陶瓷的压电性能。考察了SDBS含量对多孔陶瓷性能的影响，实验结果表明，适当增加SDBS含量促进颈部固相反应，提高机械性能及渗透性，并且提高压电性能。而当其含量过高时则会造成陶瓷性能下降。在Al₂O₃含量为8%，SDBS含量为8%，煅烧温度为1250 ^oC时可制备性能较优的多孔SiO₂压电陶瓷，其机械强度为26.8 MPa，纯水渗透率为10.2×10³ L/(m²∙h∙bar)，平均孔径为2.6 μm，原位超声波共振信号为5.3 mV。该支撑体在pH为1-13的溶液中具有良好的化学稳定性，满足膜分离的基本需求。

关键字：压电材料 α-石英 膜污染 膜分离

Abstract

Membrane separation technology has the advantages of high separation precision, separation efficiency, environmental friendliness and easy integration, and has broad application prospects in the field of water treatment. However, the water treatment membrane is easily contaminated by particles in the water system during operation, and the surface of the membrane and the pores are filled, resulting in a decrease in separation efficiency, and the separation accuracy is affected. Membrane fouling severely limits the promotion and application of membrane technology. The development of self-cleaning and anti-contamination membrane has become the focus of current membrane technology research. Piezoelectric ceramic membrane is a kind of porous separation membrane prepared by piezoelectric material, which can generate ultrasonic waves in situ during the separation process, thereby removing pollutant accumulation and alleviating membrane fouling. Piezoelectric ceramic membranes prepared based on lead zirconate titanate (PZT) have shown good anti-pollution effects and application prospects, but there are certain PZT materials with lead content up to 60% in the environment in direct contact with water. Security risks. In this experiment, lead-free piezoelectric ceramics, α-quartz as the main raw material, Al₂O₃ and sodium dodecylbenzenesulfonate (SDBS) as sintering aids were used to prepare lead-free piezoelectric ceramic carriers. The filter membrane improves the separation accuracy. The effects of calcination temperature on the properties of porous SiO₂ ceramics were investigated. The experimental results show that increasing the calcination temperature can promote the reaction between the necks of the particles, strengthen the neck joint and expand the gap between the SiO₂ particles, thereby improving the mechanical strength of the ceramics. And penetration properties. However, when the temperature reaches 1300 ^oC and above, the conversion of α-quartz to α-cristobalite weakens the piezoelectric properties of the porous ceramic. The effect of SDBS content on the properties of porous ceramics was investigated. The experimental results show that the appropriate increase of SDBS content promotes the solid phase reaction of the neck, improves the mechanical properties and permeability, and improves the piezoelectric properties. When the content is too high, the ceramic properties are degraded. When the Al₂O₃ content is 8%, the SDBS content is 8%, and the calcination temperature is 1250 ^oC, the porous SiO₂ piezoelectric ceramics with excellent performance can be prepared. The mechanical strength is 26.8 MPa, and the pure water permeability is 10.2×10³ L/(m²∙h∙bar), the average pore size is 2.6 μm, and the in-situ ultrasonic resonance signal is 5.3 mV. The lid support has good chemical stability in solutions with a pH of 1-13, meeting the basic requirements for membrane separation.

Key Words: Piezoelectric materials；Quartz；Membrane fouling；Membrane separation

目 录

摘 要 I

Abstract II

目 录 i

第一章 文献综述 1

1.1 引言 1

1.2 膜清洗 1

1.3 压电材料性质 2

1.4 压电膜研究 2

1.5 本文的研究思路与内容 3

第二章 多孔SiO₂压电陶瓷膜的制备及应用研究 4

2.1实验部分 4

2.1.1实验试剂与仪器 4

2.1.2 多孔SiO₂压电陶瓷的制备 5

2.1.3 多孔SiO₂压电陶瓷的极化与后处理 6

2.1.4 多孔SiO₂压电陶瓷的表征方法 7

2.2结果与讨论 10

2.2.1 SiO₂陶瓷粉体性能研究 10

2.2.2 烧结温度对多孔SiO₂压电陶瓷性能影响 12

2.2.3 助烧剂含量对多孔SiO₂压电陶瓷性能影响 16

2.2.4 不同pH值溶液对多孔SiO₂压电陶瓷性能影响 18

第三章 结论与展望 20

3.1 结论 20

3.2 展望 21

参考文献 22

致 谢 25

第一章 文献综述

1.1 引言

膜是一种具有选择性筛分功能的材料^[1-2]，它可以根据工程需要对悬浮物、大分子有机物、细菌甚至离子等有很好的截留效果，因此被广泛应用于食品、医疗、水处理、石油化工以及核能等众多重要领域。膜分离具有低能耗、低成本等优点，除了选择性、通量、强度外，抗污染性也是衡量膜性能的重要指标。

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