【作者】 余晓皎；

【导师】 周孝德； 姚秉华；

【作者基本信息】 西安理工大学 ， 环境工程， 2007， 博士

【摘要】 随着工农业经济的快速发展，废水的排放量日益增大，工业废水成份复杂且含有大量可利用资源，其中重金属离子以其自身的污染特点对环境造成的巨大危害而受到社会各界的高度重视。液膜分离技术具有传质速度快、选择性好、分离效率高、操作简便和易于实现自动化等特点，在分离和富集废水中的金属离子和有机污染物方面，展示了优良的性能。液膜法处理工业废水，可以实现资源回收与环境保护的双重功效，因此，在工业快速发展与自然资源日益紧张的今天，开发高效节能且具有环境效益和经济效益的液膜分离废水处理技术势在必行。本论文通过不同液膜过程，主要研究了工业废水中几种金属离子的液膜传输行为、分离富集和检测方法，获得了分离效率高、选择性好的新液膜体系，同时通过传质过程分析，建立相应的数学模型，取得以下研究结果：1、通过内耦合大块液膜体系，研究了Cu（Ⅱ）、Pb（Ⅱ）和Ni（Ⅱ）在PC-88A／CHCl₃大块液膜体系中的传输行为，并探讨了影响金属离子迁移的各种因素。结果表明，以PC-88A为载体，CHCl₃为膜溶剂的内耦合大块液膜体系对Cu（Ⅱ）、Pb（Ⅱ）、Ni（Ⅱ）具有显著的迁移和富集作用，其最佳工艺条件如下：搅拌速度分别为300～400r／min、350～400r／min、300～350r／min；料液相pH分别为3.5～5.0、2.8～3.8、5.3～5.8；载体浓度分别为5.0～7.5％、5.0～6.25％、5.5～8.5％；反应体系温度分别为288～308K、289～303K、293～310K；解析试剂H₂SO₄浓度分别为2.0mol／L、2.0mol／L、2.5mol／L。在此工艺条件下，对含Cu（Ⅱ）、Pb（Ⅱ）、Ni（Ⅱ）电镀废水进行处理，其迁移率均可达到99％以上，同时实现了三种金属离子的分离与富集。通过传质分析，证明料液相和解析相中的氢离子是金属离子通过大块液膜迁移的驱动力；迁移实验表明金属离子在大块液膜中的迁移行为宏观上具有连串反应的动力学特征，推导出金属离子通过大块液膜迁移的速率方程、R_d、R_m和R_a与准一级表观速率常数k₁和k₂的关系及金属离子迁移的通量方程，获得金属离子通过大块液膜迁移动力学参数k₁、k₂、t_max、R_m^max、J_a^max、J_d^max及反应活化能，并通过实验对动力学方程进行了验证。2、采用TBP-Span80-液体石蜡-煤油乳化液膜体系对Cu（Ⅱ）、Cr（Ⅲ）、Pb（Ⅱ）和Ni（Ⅱ）的传输行为进行了研究，探讨了影响金属离子迁移率的各种因素。结果表明，该体系对金属离子Cu（Ⅱ）、Cr（Ⅲ）、Pb（Ⅱ）和Ni（Ⅱ）具有显著的迁移和富集作用，获得最佳迁移条件如下：Span80分别为7.0％、5.0％、6.0％、4.0％；液体石蜡分别为5.0％、4.0％、5.0％、4.0％；煤油分别为80％、84％、81％、83％；载体浓度分别为9.0％、7.0％、8.0％、9.0％；解析相H₂SO₄浓度分别2.0mol／L、1.0mol／L、1.0mol／L、0.5mol／L；Roi分别为1：1、1：1、1：1、1：1；Rew分别为1：4、1：5、1：5、1：5；料液相pH分别为4.0～4.5、3.5、3.5～4.0、4.5～5.3。在此工艺条件下，对含Cu（Ⅱ）、Cr（Ⅲ）和Ni（Ⅱ）废水进行了处理，处理后的废水可直接排放（金属离子含量均低于1.0mg／L）。同时对金属离子在乳化液膜中的传质进行了分析，并建立了相应的传输动力学方程。3、研究了N503-煤油支撑液膜体系中Hg（Ⅱ）、Mo（Ⅵ）和W（Ⅵ）的传输行为。结果表明，膜浸透时间、搅拌速度、载体浓度、料液相pH、离子强度、反应体系温度、以及金属离子起始浓度对金属离子的迁移均产生影响，获得了支撑液膜体系迁移Hg（Ⅱ）、Mo（Ⅵ）、W（Ⅵ）的工艺条件如下：膜浸透时间分别为80min、60min、70min；搅拌速度分别为400～450r／min、350～400r／min、350～400r／min；载体浓度分别为15～20％、20～25％、25～30％；料液相pH分别为2.5～3.0、3.5～4.0、5.3～5.8；离子强度分别为0.4～0.8、0.3～0.6、0.3～0.6；反应体系温度分别为288～308K、288～308K、288～308K：解析试剂浓度分别为0.3mol／L（HCl）、0.25mol／L（NaOH）、0.2mol／L（NaOH）。在此工艺条件下，对溶液中的Hg（Ⅱ）与Pb（Ⅱ）、Mo（Ⅵ）与W（Ⅵ）进行了分离实验，结果表明，该体系可以实现Hg（Ⅱ）与Pb（Ⅱ）、Mo（Ⅵ）与W（Ⅵ）的有效分离。通过膜传质过程分析，建立了金属离子在支撑液膜中的传质动力学方程，计算出金属离子通过支撑液膜迁移动力学参数△_d，△_o，▲_x1，D₂，得到金属离子通过支撑液膜的渗透系数方程，通过实验验证了该方程与实验结果较为一致。更多还原

【Abstract】 The discharge of wastewater is augmenting with quick economic development of industry and agriculture. Industrial wastewater contains many ingredient and usable resource. All the community pay much attention to the environment effects of the heavy metal ions in industrial wastewater because some of metal ions can cause the heavy damages to the health of human and biological balance. Liquid membrane separation technology has exhibited an excellent character on separating and enriching metal ions and organic contaminations in the wastewater due to their fast mass transport, great selectivity, high separation efficiency, convenient processes and easy automatization. It has two layer benefit of recovered resource and environmental protection by treating industrial wastewater through liquid membrane. It is necessary to develop liquid technology of separation wastewater with quick development of industry and lack of nature resource.The transport behavior through the liquid membrane, the methods on separation, enrichment and test of metal ions using different liquid membrane systems have been studied in the present treatise. The novel liquid membrane systems with high selectivity and separation efficiency have been obtained. The mathematical model of metal ions transport in liquid membrabe systems was established by the analysis of mass transfer.The results are summarized as follows:1. The transport behavior of Cu（Ⅱ）, Pb（Ⅱ） and Ni（Ⅱ） through the bulk liquid membrane system of PC-88A/CHCl₃ is studied. The paper discussed the influencing factor upon the metal ions transfer rate. The results showed that this liquid membrane systems have marked effect upon Cu（Ⅱ）, Pb（Ⅱ） and Ni（Ⅱ）. The optimal conditions of transport are summarized as follows: stirring speed 300～400 r/min, 350～400 r/min and 300～350 r/min,respectively, feed phase pH 3.5～5.0, 2.8～3.8 and 5.3～5.8, respectively, carrier concentrations 5.0～7.5%, 5.0～6.25 %and 5.5～8.5%, respectively, reaction temperature 288～308 K, 289～303 K and 293～310 K, respectively, H₂SO₄ concentration 2.0 mol/L, 2.0 mol/L and 2.5 mol/L in stripping phase, respectively.In the conditions, treating the concentration of Cu（Ⅱ）, Pb（Ⅱ） and Ni（Ⅱ） in wastewater the transfer rate of metal ions can reach 99%. At the same time, the three metal ions can be separated. Through the analysis of mass transfer, the driving force of transportation is differences of concentration of hydrogen ion between feed phase and stripping phase. The kinetics of transportation of metal ion through bulk liquid membrane is studied and the results indicated that the transport kinetics could be analyzed in the formalism of concatenation reaction. The rate equation of transportation was obtained. The transport kinetics parameters are calculated including k₁, k₂, t_max, R_m^max, J_a^max, J_d^max and activation energy. The kinetics equation is proved by transportation experiment.2. The transfer behavior of Cu（Ⅱ）, Cr（Ⅲ）, Pb（Ⅱ） and Ni（Ⅱ） were studied using the emulsion liquid membrane system of TBP-Span80-atoleine-kerosene. The influencing factors are investigated upon the metal ions transfer rate. The results showed that this emulsion liquid membrane systems have marked effect upon Cu（Ⅱ）, Cr（Ⅲ）, Pb（Ⅱ） and Ni（Ⅱ）. The optimal transfer conditions are given as follows: Span80 7.0%, 5.0%, 6.0% and 4.0%, respectively, atoleine 5.0%, 4.0%, 5.0% and 4.0%, respectively, kerosene 80%, 84%, 81% and 83%, respectively, cartier concentrations 9.0%, 7.0%, 8.0 %and 9.0%, respectively, Roi 1:1, 1:1, 1:1 and1:1, respectively, Rew 1:4, 1:5, 1:5 and 1:5, respectively, feed phase pH 4.0～4.5, 3.5, 3.5～4.0 and 4.5～5.3, respectively.In the conditions, treating the concentration of Cu（Ⅱ）, Cr（Ⅲ） and Ni（Ⅱ） in wastewater the transfer rate of metal ions can be reduced to 1.0 mg/L. The kinetics equation of metal ions is established through the ELM.3. The transfer behavior of Hg（Ⅱ）, Mo（Ⅵ） and W（Ⅵ） were studied using the supported liquid membrane system of N503- kerosene. The study include analysis the effect of metal ions transport rate of soaking time, stirring rate, carrier concentration, pH of feed phase, ionic strength, reaction temperature, initial concentration of metal ion in feed phase. The transfer conditions are summarized as follows: soaking time 80 min, 60 min and 70 min, respectively, stirring speed 400～450 r/min, 350～400 r/min and 350～400 r/min, respectively, carrier concentrations 15～20%, 20～25% and 25～30%, respectively, feed phase pH 2.5～3.0, 3.5～4.0 and 5.3～5.8, respectively, ionic strength 0.4～0.8, 0.3～0.6 and 0.3～0.6, respectively, reaction temperature 288～308 K, 288～308 K and 288～308 K, respectively, stripping reagent concentration 0.3 mol/L （HCl）, 0.25 mol/L （NaOH）, 0.2 mol/L （NaOH）, respectively.The selective separation of Hg（Ⅱ） and Pb（Ⅱ）, Mo（Ⅵ）and W（Ⅵ） from aqueous solution with the SLM are explored, respectively. The results showed that Hg（Ⅱ） and Pb（Ⅱ）, Mo（Ⅵ）and W（Ⅵ） are separated effective through the SLM. The kinetics equation of metal ions is established in the SLM system. The transport kinetics parametersΔ_d,Δ_o,Δχ₁ and D₂ are calculated through the SLM. The osmotic coefficient equation is obtained through the SLM. The osmotic coefficient equation is proved by transportation experiment.更多还原