本文選題：鐵酸鹽尖晶石 + 硫酸根自由基　； 參考：《內(nèi)蒙古大學(xué)》2017年碩士論文

【摘要】：喹啉在制藥、印染、化工等行業(yè)普遍存在,是一種非常重要的精細(xì)化工原料。然而,如果將其釋放到環(huán)境中,對動植物均會造成嚴(yán)重的毒害作用。在煤氣化廢水中,喹啉類化合物濃度可達(dá)40mg/L以上,是僅次于苯酚類的第二大污染物。因其有毒有害、生物抑制性強(qiáng),傳統(tǒng)生化處理法無法對廢水中存在的喹啉實現(xiàn)有效降解,因此,使用高級氧化法成為處理此類廢水的發(fā)展趨勢。在高級氧化法中,硫酸根自由基氧化體系因其具有氧化性強(qiáng)、氧化速率快、pH適用范圍廣、選擇性低等特點(diǎn)逐漸脫穎而出。目前,關(guān)于硫酸根自由基的研究主要集中在高效催化劑的制備、催化劑的可回收性和重復(fù)利用率的提高、催化機(jī)理的揭示等方面。在此背景下,本研究提出使用非均相硫酸根自由基體系降解喹啉的思路。具體研究內(nèi)容包括:磁性尖晶石催化劑的制備、表征及催化活性評價;提高催化劑穩(wěn)定性及可重復(fù)利用率的研究;催化機(jī)理研究;在降解喹啉時的效能的研究。研究結(jié)果表明,使用溶膠凝膠法制備的MFe2O4(M=Co、Mn、Cu、Zn)四種催化劑中,鐵酸錳的催化效果最好。在煅燒溫度為350℃時,生成的鐵酸錳結(jié)晶完整,粒徑較小,表現(xiàn)出很好的催化效果與穩(wěn)定性。在鐵酸錳尖晶石的硫酸根自由基氧化體系中,降解甲基橙的最佳的反應(yīng)條件為:催化劑投加量1g/L、K2S2O8投加量為1g/L,此時甲基橙的降解率在90min時達(dá)到了 87.53%。催化劑的重復(fù)利用率表現(xiàn)優(yōu)越,重復(fù)使用8次后甲基橙的降解率仍然在80%以上。另外,催化劑溶出率與催化效果有一定的相關(guān)性。通過競爭動力學(xué)的方法對所生成的自由基進(jìn)行定性分析,發(fā)現(xiàn)在鐵酸鹽尖晶石的硫酸根自由基氧化體系中,SO4·-起著主導(dǎo)的作用,·OH次之。使用紫外-可見光全波長掃描來分析甲基橙的降解過程,發(fā)現(xiàn)甲基橙中的大共軛體-N=N-在反應(yīng)的過程中發(fā)生斷裂,溶液脫色,并且甲基橙中的苯環(huán)也被SO4·-攻擊,生成了小分子化合物。在降解喹啉的實驗中,最優(yōu)的反應(yīng)參數(shù)為:pH=7,K2S2O8的投加量為5g/L,催化劑的投加量為1g/L,室溫。此時,在反應(yīng)時間為60min條件下,喹啉的COD去除率可穩(wěn)定達(dá)到了83.56%。本項目的開展,為深入理解過硫酸鹽活化劑的制備及活化機(jī)理提供理論支持,為進(jìn)一步闡明含喹啉廢水降解機(jī)理及催化反應(yīng)動力學(xué)提供了數(shù)據(jù)支撐,為高效率、低成本地處理含喹啉廢水提供了新的途徑,因此,具有重要的理論價值及實踐意義。
[Abstract]:Quinoline is widely used in pharmaceutical, printing and dyeing, chemical industry and so on. It is a very important fine chemical raw material. However, if released into the environment, it can cause serious toxicity to animals and plants. In coal gasification wastewater, the concentration of quinoline compounds can reach more than 40 mg / L, which is the second largest pollutant after phenol. Because of its toxic and harmful, strong biological inhibition, the traditional biochemical treatment method can not achieve the effective degradation of quinoline in wastewater, therefore, the use of advanced oxidation process has become the development trend of treatment of such wastewater. In the advanced oxidation process, the sulfate radical oxidation system has the characteristics of strong oxidation, fast oxidation rate and wide range of pH application, low selectivity and so on. At present, the research of sulfate radical mainly focuses on the preparation of high efficient catalyst, the improvement of the recoverability and reutilization efficiency of catalyst, and the revelation of catalytic mechanism. Under this background, the idea of using heterogeneous sulfate radical system to degrade quinoline was put forward. The specific research contents include: preparation, characterization and catalytic activity evaluation of magnetic spinel catalyst; study on improving the stability and repeatability of the catalyst; study on the catalytic mechanism; and study on the efficiency in the degradation of quinoline. The results show that manganese ferrate has the best catalytic effect among the four kinds of catalysts prepared by sol-gel method. At the calcination temperature of 350 鈩，

本文編號：2095807