碳纳米管负载TiO_2及去除复合重金属废水性能研究

TiO_2-coated Carbon Nano-tubes:Preparation and Performance in Treatment of Combined Heavy-metal Containing Wastewater

以酸氧化的碳纳米管为载体,通过水热方法合成碳纳米管负载纳米二氧化钛复合物。纳米复合物采用X-射线衍射(XRD)、扫描电镜(SEM)、和比表面积(BET)测定。结果显示,负载在碳纳米管上二氧化钛为锐钛矿型,颗粒粒径在30~60 nm之间。合成样品比表面积为139.5 m^2/g。采用模拟的铅废水以及铅与丁基黄药复合废水为处理对象,对其吸附性能进行研究。当起始铅浓度为50 mg/L,溶液的pH值为5.5,吸附剂投加量为0.5 g/L,吸附时间为30 min的条件下,铅的去除效率为92.2%,饱和吸附量为92.2 mg/g。当起始铅和丁基黄药的浓度分别为50 mg/L和10 mg/L,溶液的pH值为5.5,铅和丁基黄药的去除效率分别为93.2%和99.3%。饱和吸附量为113.0mg/g。

Laboratory experiments were conducted in purpose to prepare TiO2/carbon nano-tubes （TiO2/CNTs） by hydrothermal process, and to characterize the nano-composite materials using instruments such as X-ray powder diffraction （XRD）, scanning electron microscopy （SEM） and Brunaner-Emmett-Teller （BET）. The characterization experiment indicated that nano-TiO2 was of anatase type which grew on CNTs; the TiO2 nano-particles＂ diameters ranged 30-60 nm; and the specific surface area was 139.5 m2/g. In addition, the TiO2/CNTs as a sort of adsorbent were applied to purification of wastewater containing Pb and butyl xanthate focusing on the adsorption characteristics of TiO2/CNTs, which showed that under the condition of the initial Pb concentration 50 mg/L, the adsorbent amount 0.5 g/L, reaction time 30 min, pH 5.5, the removal efficiency of Pb was 92.2%, and the saturated adsorption capacity was 92.2 mg/g. However, the removal efficiency of Pb and butyl xanthate was 93.2% and 99.3%, respectively when the initial concentrations of Pb and butyl xanthate were 50 mg/L and 10 mg/L, respectively, the amount of TiO2/CNTs was 0.5 g/L, reaction time 30 min, and pH 5.5; and the saturated adsorption capacity was 113.0 mg/g.