钨酸铋纳米复合光催化剂的制备及其应用研究

发布时间：2018-05-06 01:18

  本文选题：钨酸铋 + 石墨烯　； 参考：《青岛科技大学》2017年硕士论文

【摘要】：印染废水化学需氧量(COD)高,水量大、色度高、成分复杂且难生化降解,对人类健康、安全危害极大,是最难处理的工业废水之一,传统的处理办法很难使出水水质达到标准。光催化技术不仅可以利用清洁无污染的太阳能,还可在温和条件下将绝大部分有机物氧化降解且不会产生二次污染,极大降低了有机污染物对人体的危害,保障了人类的生命财产安全。钨酸铋(Bi_2WO_6)作为目前可见光催化活性最好的半导体材料,无论是材料本身还是原料均安全无毒,制备方法也安全有效。本文主要研究了可见光催化剂Bi_2WO_6及其复合物Bi_2WO_6/氧化石墨烯(GO)、Bi_2WO_6/氮掺杂石墨烯(NG)的制备及其在氙灯模拟日光条件下对四种模拟染料废水的降解效果,并致力于保护人类健康及生态平衡。具体内容如下:1.以Na_2WO_4·2H_2O和Bi(NO_3)_3·5H_2O为原料,采用水热法制备了三维花瓣状Bi_2WO_6光催化剂,优化了最佳制备条件,并利用SEM、XRD等方法对产品的结构和形貌进行了表征,实验结果表明:在前驱液pH=1,160℃下水热反应24h制备的Bi_2WO_6具有最佳光催化活性;同时研究了催化剂的用量、罗丹明B的初始浓度、光强以及反应时间等条件对Bi_2WO_6可见光催化降解罗丹明B效果的影响,结果发现在氙灯功率为500W的光照下,向浓度为1.0×10-5 mol·L-1罗丹明B溶液中加入0.05 g Bi_2WO_6,反应60 min时去除率达到最大,可达90.1%。2.采用Hummers法制备GO,以GO和Bi_2WO_6为原料采用一锅法制备不同质量分数的Bi_2WO_6/GO复合光催化剂,利用TEM、XRD等表征手段对复合物的形貌和结构进行了分析,并在最佳光催化反应条件下考察了复合物对四种模拟染料废水的降解效果,实验结果表明,160℃下水热反应12 h所得的GO质量分数为3%的Bi_2WO_6/GO复合光催化剂对浓度为1.0×10-5 mol·L-1的甲基橙溶液降解效果最好,达96.1%,对其余染料降解率也均在95%左右。3.以GO和Bi_2WO_6为原料,以尿素为氮源,采用一锅法制备了不同质量分数的Bi_2WO_6/NG复合光催化剂,利用TEM、XRD等方法对复合物的形貌结构进行了分析,并在最佳光催化条件下考察了复合物对四种模拟染料废水的降解效果,实验结果表明,160℃下水热反应12 h所得NG质量分数为20%的Bi_2WO_6/NG复合物对浓度为1.0×10-5 mol·L-1的罗丹明B降解效果最好,达98.9%,对其余染料降解率也均在98%左右。4.Bi_2WO_6及其复合物对有机污染物极高的降解率,不仅保护了生态环境平衡,也降低了对人类健康安全的威胁,使得人类、健康、资源更加和谐可持续发展。在可见光照射下催化降解染料废水,实际应用时以太阳光为光源,可以避免电源的使用,更加安全环保。
[Abstract]:Printing and dyeing wastewater has high chemical oxygen demand (COD), large amount of water, high chroma, complex composition and difficult biodegradability. It is one of the most difficult industrial wastewater to treat because of its great harm to human health and safety. The traditional treatment method is difficult to make the effluent quality up to the standard. Photocatalytic technology can not only utilize clean and pollution-free solar energy, but also oxidize and degrade most organic matter under mild conditions without secondary pollution, which greatly reduces the harm of organic pollutants to human body. It ensures the safety of human life and property. Bismuth tungstate Bi2WO6) is the most active semiconductor material for visible light catalysis at present. Both the material itself and the raw material are safe and non-toxic, and the preparation method is safe and effective. In this paper, the preparation of visible light catalyst Bi_2WO_6 and its complex Bi_2WO_6/ graphene oxide, Bi2WO6 / nitrogen-doped graphene (NGN), and the degradation effect of four simulated dye wastewater under simulated sunlight with xenon lamp were studied. And dedicated to the protection of human health and ecological balance. The details are as follows: 1. Three-dimensional petal Bi_2WO_6 photocatalyst was prepared by hydrothermal method using Na_2WO_4 2H_2O and Bi(NO_3)_3 5H_2O as raw materials. The optimum preparation conditions were optimized. The structure and morphology of the product were characterized by means of Na_2WO_4 2H_2O and Bi(NO_3)_3 5H_2O. The experimental results show that the Bi_2WO_6 prepared at pH=1160 鈩，

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