金属配合物交联合成及氧化降解偏二甲肼废水

发布时间：2018-05-24 14:12

  本文选题：改性壳聚糖 + 绿色催化　； 参考：《东南大学》2017年硕士论文

【摘要】：随着环境污染日益严重,对绿色化工的要求也越来越紧迫。随着火箭主体燃料偏二甲肼废水量的增加,也使得对其的处理技术受到越来越多的关注。则急需一种高效、绿色的催化剂来避免处理偏二甲肼废水时对环境的二次污染。本文采用了湿式催化氧化法配合生物高分子载体金属催化剂来处理中等浓度的偏二甲肼废水。本实验采用壳聚糖载体金属催化剂和改性壳聚糖载体金属催化剂进行系列实验来挑选最佳催化剂载体和最佳的反应条件,由此得出最佳工艺及其操作条件。通过壳聚糖和不同金属离子制备成催化剂进行偏二甲肼废水降解反应,筛选出铜离子和钴离子可以作为催化剂活性中心,其对偏二甲肼的降解都具有显著的效果,降解率均大于60%。对同种金属阳离子不同种阴离子盐制备的催化剂进行偏二甲肼废水降解反应,得出结论:制备过程中阴离子的种类对催化剂的活性的影响不大。但是由于壳聚糖自身的酸性可溶性的缺点,不能满足在降解偏二甲肼过程中稳定存在的要求。为减少催化剂中有效组分的流失,提高其催化性能,将壳聚糖负载在惰性载体SiO2上。用改性后的载体制备的不同活性中心的催化剂中,铜系列催化剂中活性最好的是Cu-Zn@CS-SiO2,其 COD 的去除率是 87.38%,NDMA 残留量为 0.31mg/L,UDMH 去除率是100%;钴系列催化剂中活性最好的是Co-Cu@CS-SiO2,其COD的去除率是84.18%,NDMA残留量为4.90mg/L,UDMH去除率是100%。通过对两个系列催化剂的研究,锌离子和锰离子作为辅助离子对偏二甲肼降解过程中产生的有毒性NDMA的降解率高。研究催化活性最好的Cu-Zn@CS-SiO2催化剂性能得出,反应中H2O2最佳的加入量是3mL;最适反应温度为65℃;催化剂可重复使用次数最多达到六次。通过SEM、EDX、FTIR和XRD表征分析,得到了催化剂的可能的结构。Fe(Ⅲ)和载体间是六配位化合物,分别是和两个O原子、两个N原子和两个水分子的配位。其他的金属离子Cu(Ⅱ)、Zn(Ⅱ)、Mn(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)和载体间是四配位化合物,分别是和一个N原子,其他三个配位是和水或者-OH的配位。
[Abstract]:With the environmental pollution becoming more and more serious, the requirement of green chemical industry is more and more urgent. With the increase of the waste water of UDMH, more and more attention has been paid to the disposal technology of UDMH. An efficient and green catalyst is urgently needed to avoid secondary environmental pollution in the treatment of UDMH wastewater. In this paper, wet-type catalytic oxidation method combined with biopolymer carrier metal catalyst was used to treat moderate concentration UDMH wastewater. In this experiment, the best catalyst carrier and the best reaction condition were selected by a series of experiments on chitosan supported metal catalyst and modified chitosan supported metal catalyst, and the optimum process and operation conditions were obtained. The catalytic degradation of unsymmetrical dimethylhydrazine was carried out by chitosan and different metal ions. Copper ion and cobalt ion can be used as the active center of the catalyst, and the degradation of unsymmetrical dimethylhydrazine has remarkable effect. The degradation rate was higher than 60%. The catalysts prepared by different anionic salts of the same metal cations were degraded by unsymmetrical dimethylhydrazine wastewater. It was concluded that the kinds of anions had little effect on the activity of the catalysts during the preparation process. However, chitosan can not meet the requirements of stability in the degradation of UDMH due to its own acid solubility. In order to reduce the loss of effective components in the catalyst and improve its catalytic performance, chitosan was supported on the inert carrier SiO2. In the catalysts with different active centers prepared from the modified support, The best activity of Cu-ZnCS-SiO2 is Cu-ZnCS-SiO2, and the removal rate of COD is 87.38 mg / L UDMH of 0.31 mg / L UDMH, and the best activity of Co-CuCS-SiO2 is Co-CuCS-SiO2. The removal rate of COD is 4.90 mg / L UDMH. Through the study of two series of catalysts, zinc ion and manganese ion were used as auxiliary ions to degrade UDMH with high degradation rate of toxic NDMA. The optimum addition amount of H2O2 is 3 mL, the optimum reaction temperature is 65 鈩，

本文编号：1929342