本文關鍵詞：二氧化錳活化過硫酸鹽降解染料廢水的研究　出處：《上海應用技術大學》2016年碩士論文　論文類型：學位論文

  更多相關文章： 硫酸根自由基 過一硫酸鹽 二氧化錳 染料 降解 機理

【摘要】：染料廢水是典型的難降解工業(yè)廢水之一,具有COD高、色度高、毒性大、可生化性差等特點。傳統(tǒng)的水污染處理技術如吸附法、絮凝沉淀法、生物降解法等難以適應新型染料廢水的處理。近年來,發(fā)展起來的以硫酸根自由基(SO_4~-·)為主要活性物種的非均相高級氧化技術引起了研究者越來越多的關注�；赟O_4~-·的非均相高級氧化技術具有以下優(yōu)點：(1)氧化劑為固體顆粒,穩(wěn)定性遠大于H_2O_2和O_3；(2)氧化劑活化產(chǎn)生SO_4~-·時受pH影響��；(3)SO_4~-·的壽命長,可極大地提高有機污染物的降解效率。Mn02是一種常見的過渡金屬氧化物,其晶型結(jié)構(gòu)的多樣性使其具有優(yōu)良的物理化學性能,被廣泛用作分子篩、氧化劑、催化劑、電池材料和傳感器材料等。因此,本論文選用MnO_2作為非均相催化材料,活化過一硫酸鹽(PMS)以產(chǎn)生SO_4~-·,研究基于SO_4~-·的非均相高級氧化技術降解不同結(jié)構(gòu)類型的有機染料的動力學與機理過程。主要研究結(jié)果如下：(1)采用水熱法制備了一種Mn02,對所制備樣品進行X射線衍射(X-ray diffraction, XRD)、掃描電鏡(Scanning electron microscope, SEM)、透射電鏡(Transmission electron microscope, TEM)、比表面積(Specific surface area, SSA)分析,其中SSA采用BET吸附理論計算。結(jié)果表明,所制備的Mn02為50-100 nnn的納米線Mn02;其比表面積約為228.7 m2/g。(2)利用MnO_2/PMS體系降解三苯甲烷染料,以孔雀石綠作為代表污染物。研究結(jié)果表明,MnO_2/PMS體系降解孔雀石綠的過程呈準一級反應動力學特點。PMS濃度、MnO_2投加量增加及溫度的升高均可提高MnO_2/PMS體系對孔雀石綠的降解效率。此外,根據(jù)阿倫尼烏斯方程計算出MnO_2/PMS體系降解孔雀石綠的活化能為47.3 kJ/mol。重復性實驗說明,MnO_2催化劑活性穩(wěn)定,可重復利用。采用紫外可見分光光度計(UV-Vis)分析降解過程中孔雀石綠的光譜變化,采用氣相色譜-質(zhì)譜聯(lián)用儀(GC-MS)分析了孔雀石綠的降解中間產(chǎn)物,進而分析了孔雀石綠的降解機理。(3)利用MnO_2/PMS體系降解咕噸染料,以羅丹明B作為代表污染物。研究結(jié)果表明,MnO_2/PMS體系降解羅丹明B的過程呈準一級反應動力學特點。PMS濃度和Mn02投加量均與羅丹明B降解反應速率常數(shù)呈線性關系。MnO_2/PMS體系不僅能快速降解羅丹明B,還能將其有效礦化。采用UV-Vis及GC-MS技術分析了羅丹明B及其降解中間產(chǎn)物的變化,相關機理也進行了探索。(4)采用乙醇(EtOH)和叔丁醇(TBA)進行自由基捕獲實驗,研究了MnO_2/PMS體系降解孔雀石綠和羅丹明B過程中的不同自由基產(chǎn)生情況,發(fā)現(xiàn)硫酸根自由基在MnO_2/PMS體系降解孔雀石綠和羅丹明B具有重要作用,進而分析了MnO_2活化PMS的機理。
[Abstract]:Dye wastewater is one of the typical refractory industrial wastewater with high COD, high chroma, high toxicity and poor biodegradability. Traditional water pollution treatment techniques such as adsorption method, flocculation precipitation method. Biodegradation is difficult to adapt to the treatment of new dye wastewater in recent years. Developed with sulphate radical (SO4S). The heterogeneous advanced oxidation technology for the main active species has attracted more and more attention. The heterogeneous advanced oxidation technology based on SO4- 路has the following advantages: 1) the oxidant is a solid particle. The stability is much greater than that of H2O2 and OSP; (2) when oxidizing agent activates to produce SO4- 路, pH has little effect on it; It is a common transition metal oxide that the degradation efficiency of organic pollutants can be greatly improved because of its long life. It is widely used as molecular sieves, oxidants, catalysts, battery materials and sensor materials for its excellent physical and chemical properties due to the diversity of crystal structure. In this paper, MnO_2 was used as heterogeneous catalytic material to activate PMSs to produce SO4- 路. The kinetics and mechanism of degradation of organic dyes with different structural types by heterogeneous advanced oxidation technology based on SOS _ 4 ~ (- 路) were studied. The main results are as follows: (1). A kind of Mn02 was prepared by hydrothermal method. X-ray diffraction (XRD) was performed on the prepared samples. Scanning electron microscope (SEM). Transmission electron microscopes (TM). The specific surface area was analyzed by specific surface area (SSAs), in which SSA was calculated by BET adsorption theory. The nanowires Mn02 with Mn02 of 50-100 nnn were prepared. Its specific surface area is about 228.7 m ~ (2 / g 路g 路m ~ (-2))) triphenylmethane dyes were degraded by MnO_2/PMS system and malachite green was used as the representative pollutant. The degradation of malachite green in MnO_2/PMS system was characterized by quasi-first-order reaction kinetics. The degradation efficiency of malachite green could be improved by increasing the dosage of MnO_2 and increasing the temperature. In addition, the degradation efficiency of malachite green could be improved by MnO_2/PMS system. According to Arrhenius equation, the activation energy of malachite green degradation in MnO_2/PMS system was calculated to be 47.3 KJ / mol 路mol. The repeatability experiment showed that the activity of the catalyst was stable. The spectral changes of malachite green during degradation were analyzed by UV-Visspectrophotometer. The degradation intermediates of malachite green were analyzed by gas chromatography-mass spectrometry (GC-MS). Furthermore, the degradation mechanism of malachite green was analyzed. The MnO_2/PMS system was used to degrade goo ton dyes, and Rhodamine B was used as the representative pollutant. The results showed that the degradation mechanism of malachite green was better than that of malachite green. The degradation of Rhodamine B in MnO_2/PMS system showed quasi-first-order kinetic characteristics. Both the concentration of PMS and the dosage of Mn02 were linearly related to the degradation rate constant of Rhodamine B. MNO _ 2. Not only can Rhodamine B be degraded rapidly by PMS system. UV-Vis and GC-MS techniques were used to analyze the changes of Rhodamine B and its degradation intermediates. The related mechanism was also explored. (4) the free radical capture experiments were carried out by using EtOH (ethanol) and TBA (tert-butanol). The production of different free radicals in the degradation of malachite green and Rhodamine B by MnO_2/PMS system was studied. It is found that sulfate radical plays an important role in the degradation of malachite green and Rhodamine B in MnO_2/PMS system. The mechanism of PMS activation by MnO_2 is analyzed.
【學位授予單位】：上海應用技術大學
【學位級別】：碩士
【學位授予年份】：2016
【分類號】：X788;TQ137.12
，

本文編號：1418919