【作者】 金玲；

【导师】 代斌；

【作者基本信息】 天津大学 ， 应用化学， 2012， 博士

【摘要】 近年来,随着我国经济的高速发展,产生了大量对环境有害的废水,饮用水源受到严重污染,并呈不断发展趋势,直接影响到社会生产和人民生活。深度水处理技术的开发和利用因而越来越受到广泛关注。等离子体污水处理技术作为一种深度水处理技术,是一种兼具高能电子辐射、臭氧氧化、紫外光分解等作用于一体的高级水处理氧化技术。半导体光催化降解技术作为一种新型的环境净化技术也越来越为人们所重视,将两种水处理高级氧化技术相结合,共同用于水处理,可以在充分利用等离子体激发的物理与化学效应的同时,利用催化剂有效降低活化能,既提高了污染物的去除效率,同时又提高了等离子体的能量利用率。本研究选用了多孔、大比表面积、吸附能力强的材料—蛭石作为载体材料。目前以蛭石为载体的相关报导很少。蛭石经不同浓度的硝酸和硫酸处理后,性能显著改善,具有良好的性能,吸附能力和比表面积显著增大。以半导体材料Ti02和ZnO为光催化剂,不同条件下酸处理改性的蛭石材料做为载体,制备了负载型光催化剂。考察了不同处理条件对晶粒尺寸和光催化剂性能的影响,并通过XRD及BET氮气吸附技术、扫描电镜等测试手段对所制备的催化剂样品进行了表征。结果表明二氧化钛催化剂样品的粒径为纳米级,酸处理的蛭石材料为介孔材料。其中,硝酸处理的效果明显优于硫酸,比表面积更大,吸附能力更强。并进而影响到负载于其上的催化剂,实验条件下,以硝酸处理的蛭石为载体的二氧化钛粒径更小。当水与浓硝酸的体积比为1/2时,处理效果最好。蛭石熔点高,热稳定性好,有利于光催化剂复合体的再生。采用以酞醇盐为原料的溶胶法制得的纳米二氧化钛-蛭石复合体,纳米二氧化钛的晶型为锐钛矿型。以亚甲基蓝为模拟污染物,分别采用紫外线光照、等离子体、等离子体放电与所制备的光催化剂结合,处理其溶液。通过比较处理效果发现,酸处理蛭石载体为光催化剂提供了高浓度的底物环境,加快了处理速度。等离子体与所制备的光催化剂相结合,协同处理的效果更好,速度更快。更多还原

【Abstract】 Recently with the high-speed development of China economy, it has been developed continuously that a great lot of waste water appeared and the drinking water sources was very much polluted, which directly affected social production and the people’s livelihood. Development and utilization of deep water treatment technology have more and more been widely attended.Wastewater treatment technology by plasma as a developing deep water treatment methods was an advanced oxidation process for wastewater treatment which was combined high-energy electron radiation, ozonation oxidation and UV-light induced photodegradation. As a new environment-purifying technique, method of semiconductor photocatalysed oxidation in degradation of organic contaminants was drawing more and more attention. It was obvious that physical and chemical effect excitation by plasma was made full use and activation energy with catalyst also effectively reduced when two methods above mentioned were used in wastewater treatment process at the same time. As a result, it promoted removal rates for the pollutants and reduced energy utilization ratio of plasma.In this study, vermiculite was used for carrier, which is a kind of porous materials possessing large specific surface area and stong absorbility. So far, research about the materials as supports was few. The material was treated by nitric acid or sulfuric acid with different concentration. It was found that the acid treatment could improve the performances of the material. Acid-treated vermiculite possessed better properties, namely were larger specific surface area and stonger absorbility. TiO2 and ZnO, which are semiconductor materials, have been used as photocatalysts and supported by acid-treated granular vermiculite. The effect of different treatment conditions on crystalline sizes and photocatalysis performance has been studied. The photocatalysts samples were investigated by used XRD, N2 adsorption analysis and scan electron microscopy. The result showed that prepared TiO2 catalysts samples were nanostructured particles and acid-treated vermiculite was mesoporous material. The treatment effect of nitric acid was superior to that of sulfuric acid. The optimal nitric acid concentration was 1:2 (v/v) condensed deionized water to nitric acid. The size of the crystal of TiO2 is influenced on support for the composite catalysts. TiO2 on the nitric acid treated vermiculite was smaller than that on the sulfuric acid treated vermiculite. The composite was easy to be reused because of high melt point and thermal stability of carrier. The nano TiO2 was prepared with sol method by the precursor, which was obtained by substituting partly isopropyl alcohol with Cl- in titanium chloride{[Ti(Ⅳ)(OR)nClm] (n=2-3, m=4-n)}. Its phase is anatase.The solution of methylene blue as simulative contaminant was treated by UV light, plasma, plasma and prepared photocatalysts, respectively. Compared the results of treatment, it was found that the substrate was concentrated by adsorption of the support in composite and rate of oxide became fast. It was best when plasma and prepared photocatalysts were used in treatment process at same time. Effect of removal was best and the rate of removal was fastest.更多还原