【作者】 李宏；

【导师】 李晓红； 王里奥；

【作者基本信息】 重庆大学 ， 环境工程， 2007， 博士

【摘要】 本研究课题系国家自然科学基金创新研究群体基金资助项目(50621403)的部分研究内容,并受重庆市自然科学基金研究项目(07BB7145)资助。多环芳烃类染料废水是持久性难降解有机污染物最主要的来源之一。尤其是当前染料正朝着抗光解、抗热及抗生物氧化方向发展,使其处理难度加大,传统的废水处理技术已经难以实现对其达标排放处理。因此,研发一种高效、经济、适用的染料废水处理技术,对于保护水环境、推动我国印染业的发展,具有积极深远的意义。本论文以多环芳烃类染料废水为处理目标,以罗丹明B染料为模拟研究对象,采用光助Fenton反应、微波强化Fenton反应和微波强化类Fenton反应,对模拟罗丹明B染料废水和实际多环芳烃类染料废水进行了实验研究。探索性地开展了以下四个方面的研究工作:(1)以太阳光、高压汞灯和室内自然光为光源,引入废铁屑参与反应,开展光助Fenton反应降解罗丹明B染料废水的降解特性研究。(2)为提高Fenton试剂法产生·OH的效率,实验采用微波作为促进手段,进行了罗丹明B染料废水降解特性的研究;同时,模拟染料废水中过渡金属离子Cr(Ⅵ)替代Fe2+参与Fenton反应,在微波强化作用下,进行罗丹明B染料废水降解特性的研究。(3)开展了光助Fenton反应、微波强化Fenton反应和微波强化类Fenton反应氧化降解的罗丹明B染料废水动力学行为研究,并对光助Fenton反应条件下,罗丹明B降解机理与途径进行了较为深入地探讨。(4)论文还对高级fenton氧化技术处理实际染料废水的产业化应用进行了系统的探讨。通过上述实验研究与理论分析,论文获得了如下研究成果:①光助Fenton反应能有效地对多环芳烃类染料罗丹明B进行脱色降解,以太阳光或高压汞灯为光源能明显加速反应进程,室内光线条件下脱色降解速率较慢;针对500ml 100mg·L-1罗丹明B溶液进行光助(高压汞灯)Fenton反应氧化降解,其反应最优化条件为:pH=3.5,18mmol·L-1Fe2+溶液用量5.0ml,30%H2O2用量5.0ml。反应1小时后,罗丹明B去除率达到99.9%,CODcr去除率达到93.8%。②微波与Fenton试剂联用,相互促进,具有一定协同效应,能加快降解有机物罗丹明B的反应速率。针对500ml 100mg·L-1罗丹明B溶液进行微波Fenton反应氧化降解,其反应最优化条件为:pH=3.0、30%H2O2溶液0.70ml、0.020mol·L-1Fe2+溶液4.00ml、微波作用8min。此时,罗丹明B去除率达到99.9%,CODcr去除率达到90.2%。③微波辐射(Cr(Ⅵ)-H2O2)类Fenton试剂法催化降解多环芳烃有机物罗丹明B取得了良好的处理效果。针对500ml 100mg·L-1罗丹明B溶液进行微波类Fenton反应氧化降解,其反应最优化条件为:pH=3.4、30%H2O2溶液1.00ml、0.040 mol·L-1Cr(Ⅵ)溶液4.00ml、微波作用8min。此时,罗丹明B去除率达到99.0%,CODcr去除率达到80.42%。④在pH=3.5的条件下,光助Fenton反应降解染料罗丹明B的反应级数为2.57,其反应的表观动力学方程为: V = 5×1 0?9×P1 .2845×F 0.3660×E0.9204;在pH=3.0的条件下,微波辐射Fenton反应降解罗丹明B的反应级数为2.13,其反应的表动力学方程为: V = 0.064085×P 0.4089×F 1.4655×E0.2562;在pH=3.4的条件下,微波辐射(Cr(Ⅵ)-H2O2)类Fenton反应降解罗丹明B的反应级数为2.85,其反应的表动力学方程为: V = 8.29182×1 0?5×P 0.8763×G 1.3719×E0.5975。⑤在光助Fenton反应条件下,羟基自由基·OH攻击罗丹明B的大共轭发色基团中不饱和共轭键,使其断裂,导致废水的脱色与氧降分解。降解过程中可能主要有罗丹明B脱去1-4个乙基后的中间产物和染色环结构破坏后生成的苯甲酸、邻苯二甲酸、对羟基苯甲酸、乙二酸等中间产物;罗丹明B分子中的氨基最终完全转化为了NO3?,废水中没有NO2 ?和N O?等其它形式的氮存在;⑥通过对Fenton高级氧化技术处理实际染料废水产业化应用的研究表明,Fenton高级氧化技术离实际产业化应用仍有不小的距离。但该技术集聚的优势,其技术操作与管理的便捷性,以及该技术废水处理成本尚有较大的下降空间,决定了Fenton高级氧化技术是一极具发展潜力的染料废水处理技术。论文的创新与学术价值在于:①避开Fenton高级氧化技术降解罗丹明B染料废水复杂的基元反应研究,开展了反应表观动力学行为研究,确立了反应表观动力学方程。从反应宏观的角度有效地掌握了该类染料废水处理技术氧化降解污染物的反应规律。从而为提高氧化降解效率,优化反应条件奠定了理论基础。②在研究光助Fenton反应氧化降解罗丹明B染料废水的中间产物与最终产物的基础上,揭示了罗丹明B氧化降解机理,并提出了罗丹明B染料废水最可能的降解途径,从而获得该染料废水处理技术氧化降解污染物的基本规律。这为探索多环芳烃类染料废水的氧化降解规律提供了重要的理论依据与技术路线。③在Fenton高级氧化技术降解多环芳烃类染料废水实验与理论研究的基础上,首次对该类技术在产业化应用过程中面临的实际染料废水的降解特性、处理规模放大后技术适应性、处理成本,以及降解过程中的卫生与毒理性等关键问题进行了系统的探讨。为推进该类染料废水处理技术产业化进程奠定了实践基础,并提供理论指导。更多还原

【Abstract】 This research subject, sponsored by CSTC (07BB7145), is part of a major creative research subject (50621403) of NFSC.Polycyclic Aromatic Hydrocarbons (PAHs) dye wastewater is one of the key sources of persistent organic pollutants which are hard to be degraded. The trend to photodegradation resistance, heat resistance and anti-biological oxidation of dyestuff especially hardens the difficulty of wastewater processing, so the traditional wastewater treatment technique cannot meet the needs of discharge standard. Therefore, it has far-reaching significance to find an economical and applicable technique of wastewater treatment with high efficiency to protect the water environment and promote the development of printing and dyeing industry.This dissertation, with the purpose of PAHs dye wastewater and Rhodamine B dyestuff as simulative research object, has an experimental research of simulative Rhodamine B and PAHS dyestuff wastewater with the adoption of Photo-Fenton reaction, microwave promoting fenton reaction and microwave promoting fenton-like reaction. Four aspects has been studied in this dissertation: (1)the degradation characteristics of Bhodamine B dyestuff wastewater of pHoto-fenton reaction are studied with the introducing of sunshine, high-voltage mercuric lamps and indoor light as lamp-house and scrap iron reaction; (2) To improve the efficiency of oxidation process, microwave-Fenton process was investigated; in the meanwhile, to avoid or lessen the secondary pollution of Fe3+ into wastewater in Fenton reaction, to broaden the usage scale of pH in Fenton reaction and to reduce the cost of the wastewater treatment bringing by the new technique and novel technology, the degradation characteristics of Rhodamine B are studied under the effect of microwave promoting and Fenton reaction in which transition metal ion Cr(VI) is used instead of Fe2+ in the wastewater;(3)the Dynamic Behavior of Rhodamine B in oxidation degradation is studied under the reactions of Photo-Fenton, microwave promoting fenton and microwave promoting fenton-like, the degradation mechanism and methods of Rhodamine B are also discussed under the reaction of Photo-Fenton;(4)the feasibility of advanced fenton oxidation technology processing dye wastewater in practical industries were discussed systemically.The following results are achieved in this dissertation from the above experimental research and theoretical analysis:①Photo-Fenton reaction can effectively decolor and degrade PAHs dye Rhodamine B, and it is more obvious under the light source of sunshine or high-voltage mercuric lamps and lower of indoor light; the oxidation degradation of optimizing conditions of Photo-Fenton reaction aimed at 500ml 100mg·L-1 Rhodamine B liquor are: pH=3.5,18mmol?L-1Fe2+ liquor 5.0ml,30%H2O2 5.00ml, and one hour later, the removal rate of Rhodamine B reaches 99.9% and CODcr is 93.8%.②The co-use and Synergistic effect of microwave and Fenton reagent can speed the degradation of Rhodamine B. The optimizing oxidation degradation conditions of 500ml 100mg·L-1 Rhodamine B reagent in Microwave-Fenton are: pH=3.0, 0.70ml 30% H2O2 liquor, 4.00ml 0.020mol·L-1 Fe2+ liquor, microwave 8min and the removal rate of Rhodamine B reaches 99.9%, while CODcr is 90.2%.③The catalytic degradation or Rhodamine B with micro radiation(Cr(Ⅵ) -H2O2)Fenton-like reagent has achieved favorable results; the optimizing oxidation degradation conditions of 500ml 100mg·L-1 Rhodamine B reagent in microwave-Fenton are: pH=3.4, 1.00ml 30% H2O2 liquor, 4.00ml 0.040 mol·L-1 Cr(Ⅵ) liquor, microwave 8min and the removal rate of Rhodamine B reaches 99.9%, while CODcr is 80.24%.④Under the condition of pH=3.5, the degradation reaction order of dye Rhodamine B of pHoto-Fenton is 2.57, and apparent kinetics equation is V = 5×1 0?9×P1 .2845×F 0.3660×E0.9204; pH=3.0, the reaction oder of microwave promoting Fenton is 2.13 and the equation is V = 0.064085×P 0.4089×F 1.4655×E0.2562;pH = 3.4, the reaction order of microwave(Cr(Ⅵ)-H2O2)promoting Fenton-like reagent is 2.85 and the equation is V = 8.29182×1 0?5×P 0.8763×G 1.3719×E0.5975。⑤Under the reaction of Photo-Fenton, Hydroxyl·OH will attack unsaturated conjugation bond of conjugated Chromophoric Group in Rhodamine B, make it broken and lead to the analytic oxidation of dyestuff. During the analytic process, Rhodomind B mainly remove the intermediate product of 1-4 Ethyl and other intermediate products produced after the break of Chromophoric Ring structure, such as Benzoic Acid, phthalic Acid, 4-Hydroxybenzoic Acid and oxalic acid; amido in Rhodamine B is changed into NO3? totally and there is no other form of nitrogen existed like NO2 ? and N O?in the wastewater.Moreover, on the analysis basis degradation Pathways for Rhodomind B was proposed.⑥In addition,preliminary feasibility analysis the application of Fenton advanced oixdation process in industries were carried out, and it was considered that there is still a huge gap between Fenton advanced oxidation technology and its use into practice. However, Fenton advanced oxidation technology is one potential dye wastewater treatment technology because of its advantages, the convenience of operation and management and the declining space of technology treatment.The major creative parts and learning values are as the followings:①Instead from the aspect of primitive reaction of Rhodamine B dye waste water degraded from Fenton Advanced Oxidation Technology, the research of this dissertation is focused on the study and equation establishment of reactive apparent dynamic behavior, grasping the reactive rule of pollutants oxidative degradation of this kind of dye waste water treatment techniques and thus settling the theoretical foundation of accelerating the oxidative degradation and optimizing the reactive conditions.②O n the basis of the intermediate and final products of Rhodamine B dye waste water after photo-Fenton reaction oxidative degradation, this dissertation has revealed the oxidative degradation mechanism of Rhodamine B, proposing the possible degradative approaches of Rhodamine B dye waste water, achieving the basic rule of pollutants oxidative degradation of this kind of dye waste water treatment techniques and proposing the critical theoretical foundation and techniques of exploring the oxidative degradation rule of PAHs dye waste water.③On the basis of PAHs dye waste water experiments and theoretical studies ofFenton advanced oxidation technology, this dissertation, for the first time, has systematically discussed the following key questions, such as the degradative characteristics of the dye waste water in the practice of industry, the technological adaptability after the spread of treatment dimensions, the cost of treatment and the sanitation, toxicity and logos during the degradative process, thus establishing the practice foundation of boosting the industrialization of this kind of dye waste water treatment techniques and providing the theoretical guidance for it.更多还原