改性多壁碳纳米管对水中Sb（Ⅲ）的去除效能及机理研究

发布时间：2018-06-24 00:48

  本文选题：碳纳米管 + Sb(Ⅲ)　； 参考：《浙江大学》2013年硕士论文

【摘要】：随着我国工业化进程的加速和城市化水平的提高,很多城市的饮用水源中有毒有机污染物和痕量重金属含量明显增加,水质安全的状况日益严重。锑(Sb)是自然界存在的一种有毒元素,作为重要的战略资源,锑被广泛应用于刹车片、阻燃剂、医药等行业。近十几年来,人类对锑的需求和消耗倍增,促进了锑矿资源的大规模开发,这一定程度上增加了环境水体中锑的含量。加之目前我国仍未对工业废水中锑的排放标准作出相应的规定,水体中的锑污染问题日益严重。以往研究表明,锑是一种较难去除的重金属,而现有除锑技术的研究仍尚显不足,为此,本文以寻求先进高效的除锑方法作为研究目标。本论文以新型纳米材料碳纳米管(CNTs)为载体,采用金属氧化物负载改性的方法制备新型复合材料Fe2O3/CNT及MnO2/CNT,并探讨了它们对水中Sb(Ⅲ)的吸附性能及机理。 本文第一部分采用负载改性法中的液相化学沉积法成功制备了Fe2O3/CNT复合材料。并利用X射线衍射仪(XRD)、激光粒度仪、扫描电镜(SEM)、透射电镜(TEM)、BET和傅里叶红外光谱仪(FTIR)对改性前后CNTs的物化性能进行了表征。通过对水中Sb(Ⅲ)的静态吸附试验考察了改性碳纳米管的吸附容量,同时还考察了pH值、锑的初始浓度、吸附剂投加量、吸附时间和温度对吸附效果的影响。结果表明,在Sb(Ⅲ)初始浓度为1.5mg/L、吸附剂投加量为0.5g/L、温度为298K、pH值为7.00的条件下,Fe203改性后的碳纳米管对锑的去除率可达到99.97%,比未改性碳纳米管的去除率提高了29.81%,吸附容量也从原始CNTs的3.01mg/g增大到6.23mg/g。最后发现该吸附过程较好地符合Freundlich吸附等温线,吸附效果几乎不受pH值的影响。 本文第二部分探讨了MnO2改性碳纳米管对锑的去除情况。采用液相氧化还原法成功制备了MnO2/CNT复合材料,并利用X射线衍射仪(XRD)、扫描电镜(SEM)、透射电镜(TEM)、BET和激光粒度仪对改性前后CNTs的物化性能进行了表征。通过对水中Sb(Ⅲ)的静态吸附试验考察了改性碳纳米管的吸附容量,同时还考察了pH值、锑的初始浓度、吸附剂投加量、吸附时间和温度对吸附效果的影响。结果表明,在Sb(Ⅲ)初始浓度为1.5mg/L、吸附剂投加量为0.5g/L、温度为298K、pH值为2.00的条件下,二氧化锰改性后的碳纳米管对锑的去除率可达到97.72%,比未改性碳纳米管的去除率提高了51.29%,吸附容量也从原始CNTs的3.01mg/g增大至6.00mg/g,吸附过程较好地与Freundlich吸附等温线符合。试验中,pH值对吸附效果的影响较大,仅在pH值为2.00附近去除效果较好,其他pH值条件下去除效果不理想。 研究表明Fe2O3/CNT和MnO2/CNT对溶液中Sb(Ⅲ)有着强于传统吸附材料的去除能力,且Fe2O3/CNT在除锑性能方面要优于MnO2/CNT。本研究将为处理水溶液中的痕量有害离子提供一个相对经济、高效和易于操作的方法。
[Abstract]:With the acceleration of industrialization and the improvement of urbanization in China, the contents of toxic organic pollutants and trace heavy metals in drinking water sources of many cities have increased obviously, and the situation of water quality safety is becoming more and more serious. Antimony (SB) is a toxic element in nature. As an important strategic resource, antimony is widely used in brake pads, flame retardants, medicine and other industries. In recent years, the human demand and consumption of antimony have doubled, which has promoted the large-scale development of antimony resources, which to some extent has increased the content of antimony in environmental water. In addition, the discharge standard of antimony in industrial wastewater has not been regulated in China at present, and the problem of antimony pollution in water is becoming more and more serious. Previous studies have shown that antimony is a kind of heavy metal which is difficult to remove, but the existing antimony removal technology is still insufficient. Therefore, the aim of this paper is to seek advanced and efficient antimony removal methods. In this paper, the novel composites Fe _ 2O _ 3 / CNT and MNO _ 2 / CNT were prepared by metal oxide supported modification with carbon nanotubes (CNTs), and their adsorption properties and mechanism for SB (鈪，

本文编号：2059212