二氧化钛纳米线光催化法降解含油污水技术研究

发布时间：2018-03-06 08:01

本文选题：二氧化钛纳米线　切入点：光催化降解　出处：《清华大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,我国大部分油田已进入开发的中后期,油田采出水量的不断增大,部分油田已经无法完全回注,因此含油污水的达标排放就成了油田公司环境保护工作中面临的一大难题。含油污水的成分也越来复杂,除含有常规的石油类、悬浮物等以外,还含有乙酸、丙酸、环己酸、辛酸等低级脂肪酸,以及苯酚类化合物和甲苯、邻二甲苯、间二甲苯、对二甲苯等苯系物,还有氯化物、硫化物等无机污染物,常用的表面活性剂中还含有十二烷基硫酸钠等无机钠盐,处理不当会对严重影响油田周边地表、地下水环境。本文建立了100g级二氧化钛纳米线的合成方法,开发了实验室内小型光催化降解装置,并设计出实验室规模污水连续光催化降解装置,为工业化装置研发打下了良好基础。成功合成锐钛矿型二氧化钛单晶纳米线催化剂。采用XRD、XPS、SEM、TEM、HRTEM等技术对催化剂的晶体结构、能带、表面形貌和颗粒尺寸等表征结果表明,获得的二氧化钛纳米线为锐钛矿相单晶,线体,合成的二氧化钛催化剂催化活性高,与P25相当,且易于回收,经循环使用后催化效率无明显下降。对有机废水中常见的多种有机物和含油污水降解实验结果表明,采用合成的二氧化钛纳米线光催化处理有机污水处理效果好,没有明显的选择性,含油污水经处理后COD可以降到《污水综合排放标准》GB8978-1996(1999年局部修订)中的一级排放标准以下。二氧化钛纳米线光催化对含油污水中的苯系物有比较明显的去除作用,当反应时间为6h时,废水中苯的浓度为72.35μg/L,其他苯系物的去除率都在为95%以上,出水完全满足《污水综合排放标准》GB8978-1996(1999年局部修订)中的第二类污染物最高允许排放浓度一级标准限值。
[Abstract]:In recent years, most of the oil fields in China have entered the middle and late stage of development, and the production capacity of the oil fields is increasing continuously, and some of the oilfields can no longer be completely injected back. Therefore, the standard discharge of oily sewage has become a major problem in the environmental protection work of oil field companies. The composition of oily sewage has become more and more complicated. In addition to the conventional petroleum, suspended matter and so on, it also contains acetic acid, propionic acid, cyclohexanoic acid, etc. Lower fatty acids such as octanoic acid, phenol compounds and toluene, o-xylene, m-xylene, p-xylene and other benzene series, as well as inorganic pollutants such as chlorides, sulfides, etc. The commonly used surfactants also contain inorganic sodium salts such as sodium 12 alkyl sulfate. Improper treatment will seriously affect the surface of the oil field and the groundwater environment. In this paper, a synthetic method of 100g titanium dioxide nanowires has been established. A small photocatalytic degradation device was developed in the laboratory, and a continuous photocatalytic degradation device for wastewater on a laboratory scale was designed. The results show that the crystal structure, energy band, surface morphology and particle size of the catalyst are characterized by XRDX XPS Sem Tem TEM. The synthesized TIO _ 2 nanowires are anatase phase single crystal, the synthesized titanium dioxide catalyst has high catalytic activity, is comparable to P25, and is easy to be recovered. After recycling, the catalytic efficiency was not significantly decreased. The results of degradation experiments of organic wastewater and oily wastewater showed that the synthetic titanium dioxide nanowires were effective in photocatalytic treatment of organic wastewater. There is no obvious selectivity. After treatment, the COD of oily sewage can be reduced below the first class discharge standard in Integrated sewage discharge Standard (GB 8978-1996) (partially revised in 1999). Titanium dioxide nanowire photocatalysis has obvious removal effect on benzene series in oily sewage. When the reaction time is 6h, the concentration of benzene in wastewater is 72.35 渭 g / L, and the removal rate of other benzenes is above 95%. The effluent completely meets the first standard limit of the maximum allowable discharge concentration of the second kind of pollutants in GB8978-1996 (partially revised in 1999).
【学位授予单位】：清华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X741

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