水中镉的胶束强化超滤净化及快速检测方法研究

【作者】 颜莎；

【导师】 满瑞林；

【作者基本信息】 中南大学 ， 化学工程， 2010， 硕士

【摘要】 论文针对水环境中低浓度镉的快速检测和治理进行了系统研究,旨在为工厂矿山提供简易、廉价、快速的处理方法和测定手段。本文首先研究了水中微量镉的双波长快速分光光度法,该法利用1-(4-硝基苯基)-3-(4-苯基偶氮苯基)-三氮烯(镉试剂)与镉(Ⅱ)离子的显色反应,在非离子表面活性剂Triton X-100存在下,配合物在478nm和566nm出现正负两个最大吸收峰,利用双波长进行快速测定。最佳测定条件为：0.2g/L显色剂用量2 ml；体系酸度pH 10.6；表面活性剂10%Triton X-100用量2 ml,显色时间30 min；配合物最大吸收波长478 nm。在此条件下,镉(Ⅱ)在0-8μg/25mL范围内服从比尔定律,表观摩尔吸光系数为2.44×105L/(mol.cm)。方法的检出限为1.4μg/ml;平均回收率为102.25%；相对标准偏差均小于5%,样品测定值与原子吸收法相吻合。论文对胶团强化超滤技术处理含镉废水进行了研究,系统考察了不同工艺参数的影响,优化了工艺条件,结果表明,对于浓度为100mg／L的含镉废水,十二烷基磺酸钠浓度为0.008mol/L、操作压力为23KPa,镉的去除率可达98%以上。在23KPa之前,渗透通量与操作压力之间是线性关系,增加压力会使得渗透通量成正比增加。超过23KPa之后,渗透通量的增加趋于平缓,达到一个稳定值,操作压力对截留率并没有明显的影响,23KPa较为合适。截留率随溶液pH值的升高而升高,能达到98%以上。更多还原

【Abstract】 This paper introduced detection methods and treatment measures on waste water containing cadmium(Ⅱ), and it could be used as reference to treat waste water and fast dictation of cadmium(Ⅱ) in mine environmental.The effect of surfactant on the colour reaction of Cadion,1-(4-nitrophenyl)-3-(4-phenylazophenyl)-triazene, with cadmium(Ⅱ) was studied in this paper. In the presence of Triton X-100, the maxium absorption wavelength is at 478nm and the maxium negative absorption wavelength is at 566nm. The best determining conditions for cadmium were obtained, the 0.2g/L developer amount used is 2 ml; the pH of system acidity is 10.6; the surface active agent,10%Triton X-100,amount used is 2 ml. And determines the colored time is 30 min; the preparation biggest absorption wave length of complex is 478nm. Under best experimental condition, Beer’s law is obeyed in the concentration range of 0-8μg cadmium(Ⅱ) in 25mL solution. The molar absorptivity is 2.44×105 L/(mol·cm). The detection limit was 1.4μg/ml.;the average recovery efficiency was 102.25% and the relative standard deviation all less than 5%. The sample results have no significance difference compared with AAS method.Micellar Enhanced Ultra Filtration (MEUF) is a novel technology which is used to treat wastewater containing metal ions. Using positive-negative peaks dual-wavelength spectrophotometry, this research is based on dealing with the waste water containing cadmium(Ⅱ) by MEUF and it has investigated the effect on this technology by the process parameter comprehensively. While treating waste water containing 100mg/L cadmium(Ⅱ), it is not necessary to increase the concentration of SDS in the solution blindly.0.008mol/L is an appropriate value. Too high transmembrane pressure can not bring the corresponding high flux. There is a critical value of transmembrane pressure. When exceeding this value, the flux of permeate will not increase obviously. The transmembrane pressure has no obvious influence on retention rate. 23KPa is appropriate. The retention rate can be more than 98% with rising pH value solution.更多还原