冷凝水论文：湿式催化氧化-光催化深度处理载人航天器冷凝水的研究.doc

冷凝水论文：湿式催化氧化/光催化深度处理载人航天器冷凝水的研究【中文摘要】载人航天器中,水是最大的生保消费品,而航天器中储水系统体积有限,若通过天地间往返运输补给,成本是难以接受的。对航天器中的冷凝水进行深度处理与回用,是解决航天员饮用水供给的重要途径。本文提出了湿式催化氧化光催化组合工艺深度处理冷凝水的技术方案。湿式催化单元采用无泡膜供氧催化氧化反应器,以Pt/AC为催化剂,氧气作为氧化剂以无泡的形式透过微孔膜进入催化反应区,参与催化反应,催化降解冷凝水中的有机污染物。反应器运行过程中无气泡产生,因此避免了微重力下的气液分离问题。采用乙二醇【英文摘要】Water is the maximum consumables of the Life Support system. As the capacity of water storage is limited and the costs of resupply from the ground are prohibitive, recycling of humidity condensate is necessary for long-term space missions. A composite technology of wet catalytic oxidation and photocatalytic oxidation was investigated for application in humidity condensate purification and recovery in this paper.Membrane bubbleless aeration wet catalytic oxidation reactor was used in the wet catalytic oxidation unit. In the reactor, Pt/AC and oxygen were employed as catalyst and antioxidant, respectively. Inside the reactor, the Pt/AC catalyst promotes the oxidation of organic contaminants by oxygen permeated through the membrane. The gas-liquid separation was avoided due to the bubbleless aeration. The Pt/AC catalyst were prepared by impregnation-chemical reduction method with glycol reductant. The candidate membranes were compared using a stirred cell filled with deaerated water to determine the mass transfer coefficient of oxygen. Finally, we chose PTFE（0.45m） as the aeration membrane.TiO2 nanotube array was prepared by the anodic oxidation method in the NH4F+ glycerin+H2O electrolyte system. The effects of anodic potential, current density, electrolyte composition and annealed temperature on the nanotube morphology and Catalytic properties were investigated. The results indicate that the H2O content of the electrolyte obviously influences the nanotube morphology while annealed temperature only influences the crystalline phase of TiO2 nanotube array film. For the 1wt%NH4F+67% glycerin +33%H2O electrolyte, TiO2 nanotube arrays can be regularly formed in the potential range between 10 and 40V. The photocatalytic activity of TiO2 nanotube array was evaluated by the degradation of Rhodmine B, and the photocatalytic degradation of Rhodmine B is first-order reaction. The samples fabricated with anodic voltage of 30V, current density of 100mA cm-2 for 120 minutes in 1wt%NH4F+67% glycerin +33%H2O electrolyte and then annealed at 500showed a better photocatalytic activity, the rate constants of the photocatalytic degradation of Rhodmine B is 0.0132min-1. The Ag-TiO2 nanotube was prepared by photochemical deposition method in AgNO3 aqueous solution.The TiO2 nanotube loaded with silver in 1 g/Lsilver AgNO3 solution possessd the best photocatalytic activity, and the rate constants of the photocatalytic degradation of Rhodmine B is 0.0141min-1.A system for treating humidty condensate was studied, including a composite technology of wet catalytic oxidation and photocatalytic oxidation. When the flux rate was 5mL min-1（HRT in wet catalytic oxidation reactor and photocatalytic oxidation reactor were 8.3min, 100min respectively）, the removal rate of organic pollutants in effluent was almost 100%. The photocatalytic unit also played an important role in disinfecting the humidty condensate.【关键词】冷凝水 无泡供氧 光催化 TiO2纳米管 湿式催化氧化【英文关键词】humidty condensate membrane bubbleless aeration photocatalytic TiO2 nanotube array wet catalytic oxidation【目录】湿式催化氧化/光催化深度处理载人航天器冷凝水的研究摘要4-5Abstract5-6第1章 绪论10-301.1 课题背景101.2 冷凝水处理现状10-141.2.1 冷凝水来源及水质特征101.2.2 国外航天器中饮用水供给10-111.2.3 冷凝水处理工艺11-141.3 无泡供氧技术简介14-161.3.1 基本原理及优缺点14-151.3.2 无泡供氧技术的分类151.3.3 无泡供氧技术的应用15-161.4 Ti0_2 光催化研究现状16-281.4.1 Ti0_2 光催化原理16-171.4.2 Ti0_2 光催化剂的制备17-211.4.3 Ti0_2 光催化剂的改性21-261.4.4 Ti0_2 纳米管阵列的研究现状26-281.5 论文的研究内容28-30第2章 实验材料与方法30-372.1 实验仪器与试剂30-312.1.1 实验试剂302.1.2 实验仪器30-312.2 湿式催化氧化反应器31-342.2.1 污染物分析方法31-322.2.2 Pt/AC 催化剂的制备322.2.3 膜供氧性能分析试验32-332.2.4 湿式催化氧化反应器33-342.3 光催化氧化反应器34-362.3.1 Ti0_2 纳米管光催化的制备34-352.3.2 Ti0_2 纳米光催化剂的掺杂352.3.3 Ti0_2 纳米催化剂的表征352.3.4 Ti0_2 纳米管的光化学实验352.3.5 Ti0_2 纳米管的光电化学实验35-362.4 湿式催化氧化光催化氧化组合反应器36-37第3章 湿式催化氧化体系的建立37-533.1 引言373.2 膜材料的选择37-483.2.1 微孔曝气的膜材料37-383.2.2 不同膜材料供氧性能比较38-483.3 催化剂的制备483.4 催化氧化反应器的构建48-503.4.1 膜结构参数的影响48-493.4.2 供氧压力的影响49-503.5 催化氧化反应器的运行50-513.5.1 催化氧化反应器对冷凝水的处理503.5.2 催化氧化反应器的持续运行能力50-513.6 本章小结51-53第4章 湿式催化氧化光催化组合工艺处理冷凝水53-724.1 引言534.2 Ti0_2 纳米管光催化剂的制备及表征53-544.2.1 Ti0_2 纳米管制备装置534.2.2 Ti0_2 纳米管阵列的制备53-544.2.3 Ti0_2 纳米管阵列的表征544.3 Ti0_2 纳米管阵列的形成及其光催化性能54-684.3.1 纳米管状结构Ti0_2 催化剂的形成54-604