本文選題：改性殼聚糖 + 綠色催化　； 參考：《東南大學》2017年碩士論文

【摘要】：隨著環(huán)境污染日益嚴重,對綠色化工的要求也越來越緊迫。隨著火箭主體燃料偏二甲肼廢水量的增加,也使得對其的處理技術受到越來越多的關注。則急需一種高效、綠色的催化劑來避免處理偏二甲肼廢水時對環(huán)境的二次污染。本文采用了濕式催化氧化法配合生物高分子載體金屬催化劑來處理中等濃度的偏二甲肼廢水。本實驗采用殼聚糖載體金屬催化劑和改性殼聚糖載體金屬催化劑進行系列實驗來挑選最佳催化劑載體和最佳的反應條件,由此得出最佳工藝及其操作條件。通過殼聚糖和不同金屬離子制備成催化劑進行偏二甲肼廢水降解反應,篩選出銅離子和鈷離子可以作為催化劑活性中心,其對偏二甲肼的降解都具有顯著的效果,降解率均大于60%。對同種金屬陽離子不同種陰離子鹽制備的催化劑進行偏二甲肼廢水降解反應,得出結論:制備過程中陰離子的種類對催化劑的活性的影響不大。但是由于殼聚糖自身的酸性可溶性的缺點,不能滿足在降解偏二甲肼過程中穩(wěn)定存在的要求。為減少催化劑中有效組分的流失,提高其催化性能,將殼聚糖負載在惰性載體SiO2上。用改性后的載體制備的不同活性中心的催化劑中,銅系列催化劑中活性最好的是Cu-Zn@CS-SiO2,其 COD 的去除率是 87.38%,NDMA 殘留量為 0.31mg/L,UDMH 去除率是100%;鈷系列催化劑中活性最好的是Co-Cu@CS-SiO2,其COD的去除率是84.18%,NDMA殘留量為4.90mg/L,UDMH去除率是100%。通過對兩個系列催化劑的研究,鋅離子和錳離子作為輔助離子對偏二甲肼降解過程中產(chǎn)生的有毒性NDMA的降解率高。研究催化活性最好的Cu-Zn@CS-SiO2催化劑性能得出,反應中H2O2最佳的加入量是3mL;最適反應溫度為65℃;催化劑可重復使用次數(shù)最多達到六次。通過SEM、EDX、FTIR和XRD表征分析,得到了催化劑的可能的結構。Fe(Ⅲ)和載體間是六配位化合物,分別是和兩個O原子、兩個N原子和兩個水分子的配位。其他的金屬離子Cu(Ⅱ)、Zn(Ⅱ)、Mn(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)和載體間是四配位化合物,分別是和一個N原子,其他三個配位是和水或者-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，

本文編號：1929342