【摘要】：非均相Fenton法在反應(yīng)過(guò)程中產(chǎn)生的·OH自由基具有強(qiáng)氧化性,是高級(jí)氧化技術(shù)中去除難降解有機(jī)物的有效手段的一種。本文以非均相Fenton技術(shù)為基礎(chǔ),制備多種負(fù)載型催化劑,多方位研究了催化劑對(duì)苯酚的降解效果等。本文采用浸漬法制備了以MCM-41和A1203為載體的催化劑,負(fù)載鐵性和銅性的活性金屬,篩選出MCM-41載體和Fe(NO3)3·9H2O活性成分。采用改進(jìn)的Hummers法制備出氧化石墨烯(GO),利用高溫回流法制備出石墨烯改性MCM-41分子篩負(fù)載鐵金屬催化劑,比較了Al-MCM-41-Fe、gh-Al-MCM-41-Fe和gh-MCM-41-Fe三種催化劑對(duì)苯酚降解效果的影響,利用SEM、比表面積、XRD表征手段對(duì)催化劑的化學(xué)價(jià)態(tài)、形貌進(jìn)行分析。結(jié)果表明：gh-Al-MCM-41-Fe催化劑具有介孔結(jié)構(gòu),石墨烯加入后顆粒粒徑減小,反應(yīng)90min, pH在3.0時(shí),苯酚降解率100%,COD去除率達(dá)到62.16%,鐵溶出為0.06 mgoL-1,并且拓寬pH范圍,降低鐵溶出,減小了二次污染。采用另一種方法水熱晶化法制備石墨烯改性MCM-41分子篩負(fù)載鐵金屬催化劑gh-MCM-41-Fe,對(duì)材料形貌、結(jié)構(gòu)、官能團(tuán)進(jìn)行了SEM、 TEX、XRD、XPS等表征,并考察了材料制備工藝及反應(yīng)條件。結(jié)果表明：制備的gh-MCM-41-Fe催化劑相比MCM-41-Fe具有更大的比表面積和孔容,有更好的介孔分子篩結(jié)構(gòu),并且氧化石墨烯在制備過(guò)程中熱還原為石墨烯,其所負(fù)載金屬呈α-Fe2O3型態(tài)晶體。當(dāng)pH=3.0,石墨烯負(fù)載量為30 mL,鐵離子負(fù)載量為5%,焙燒溫度為550-550℃,催化劑投加量0.5 g·L-1,苯酚初始濃度100 mg·L-1, H2O2初始濃度9.8mmol·L-1, T=298 K時(shí),反應(yīng)90 min, gh-MCM-41-Fe對(duì)苯酚降解率接近100%,COD和TOC去除率分別達(dá)到63%和38.89%,鐵溶出濃度為0.825 mg·L-1,表觀活化能為18.43 kJ·mol-1,反應(yīng)符合準(zhǔn)一級(jí)動(dòng)力學(xué)模型。相比MCM-41-Fe催化劑,提高了催化效能,石墨烯的摻雜降低了鐵溶出,減少二次污染,并且研究還發(fā)現(xiàn)草酸和腐殖酸的添加會(huì)抑制苯酚的降解。
[Abstract]:The hydroxyl radical produced by heterogeneous Fenton process has strong oxidation property and is an effective method to remove refractory organic compounds in advanced oxidation technology. In this paper, based on heterogeneous Fenton technology, various supported catalysts were prepared and the degradation efficiency of phenol was studied. In this paper, the active metals supported on MCM-41 and A1203 supported on iron and copper were prepared by impregnation method. The active components of MCM-41 and Fe (NO3) 3 9H2O were screened out. Graphene oxide (GO), was prepared by modified Hummers method and graphene modified MCM-41 molecular sieve was prepared by high temperature reflux method. The effects of three kinds of catalysts, Al-MCM-41-Fefeng-Al-MCM-41-Fe and gh-MCM-41-Fe, on the degradation of phenol were compared. The chemical valence and morphology of the catalyst were analyzed by means of SEM, specific surface area and XRD. The results show that the catalyst has mesoporous structure, and the particle size decreases after the addition of graphene. When the reaction time is 90 min and pH is 3.0, the degradation rate of phenol reaches 62.16% and the iron dissolution is 0.06 mgoL ~ (-1), and the range of pH is widened, the iron dissolution is reduced, and the secondary pollution is reduced. Graphene modified MCM-41 zeolites were prepared by hydrothermal crystallization method. The morphology, structure and functional groups of the materials were characterized by SEM, TEXX RDX XPS, and the preparation process and reaction conditions were investigated. The results show that the prepared gh-MCM-41-Fe catalyst has larger specific surface area, larger pore volume and better mesoporous molecular sieve structure than MCM-41-Fe, and graphene oxide is thermally reduced to graphene, and the supported metal is 偽 -Fe _ 2O _ 3 crystal. When pH is 3.0, the loading amount of graphene is 30 mL, the loading amount of iron ion is 5, the calcination temperature is 550-550 鈩，

本文編號(hào)：2140559