本文選題：Fe_2O_3 + 復(fù)合氧化物��； 參考：《廣西大學(xué)》2017年碩士論文

【摘要】：熱催化脫氯技術(shù)用于處理污染有機(jī)物具有廉價(jià)、高效、安全等優(yōu)點(diǎn),借助該手段對(duì)氯代芳烴有機(jī)物進(jìn)行降解已受到眾多學(xué)者的廣泛關(guān)注。本文選取Fe2O3、Fe-Al復(fù)合氧化物、赤泥三類金屬氧化物作為催化劑,以土壤中的PCB30為處理對(duì)象,研究了以上三類金屬氧化物對(duì)多氯聯(lián)苯的降解效果。探討了影響Fe2O3催化效果的各種因素,并通過(guò)中心響應(yīng)面分析法對(duì)Fe2O3降解PCB30進(jìn)行條件優(yōu)化。考察了Fe-Al復(fù)合氧化物不同配比、投加量等不同條件下催化效率;制備Bi改性赤泥顆粒并探討其對(duì)土壤中PCB30的催化降解效果,對(duì)處理?xiàng)l件進(jìn)行優(yōu)化,將赤泥顆粒進(jìn)行重復(fù)回用試驗(yàn),探討赤泥顆粒作為催化劑對(duì)土壤的影響。(1)通過(guò)CCD中心響應(yīng)面分析法探討土壤中PCB30在Fe2O3催化作用下的降解效果發(fā)現(xiàn),最佳催化條件為:催化劑投加量0.23g,反應(yīng)溫度333.33℃,反應(yīng)時(shí)間38 min,該條件下理論降解率為99.9%,實(shí)際驗(yàn)證下平均降解率為99.7%,所建立模型對(duì)催化降解效率的預(yù)測(cè)準(zhǔn)確可靠;(2)由共沉淀法制備出的Fe-Al復(fù)合氧化物對(duì)PCB30具有良好的催化性能,在一定制備條件下優(yōu)于單個(gè)金屬氧化物催化效果。不同F(xiàn)e、Al配比對(duì)復(fù)合氧化物催化效果具有較大影響,當(dāng)摩爾比為1:1時(shí)達(dá)到最佳,添加量為0.1g時(shí),降解率可達(dá)76.73%。其中Fe元素以Fe2O3、Fe2O3·H2O以及Fe1.833(OH)0.5O0.25等物相存在,Fe2O3為主要形態(tài),Al元素僅以Al2O3形態(tài)存在;(3)赤泥中Fe元素主要以赤鐵礦形式存在,少量以針鐵礦形式存在,赤泥中還存在少量鈣鋁榴石、明礬石、七鋁酸十二鈣以及原硅酸鈣等復(fù)合氧化物。經(jīng)過(guò)Bi改性后赤泥顆粒較之未改性赤泥顆粒有更加良好的催化降解PCB30效果,當(dāng)焙燒溫度為500℃,Bi摻雜量為8g時(shí)催化劑性能最佳。在300℃下處理30 min,PCB30降解率可達(dá)92.48%。赤泥顆粒作為催化劑在加熱條件下對(duì)土壤只造成Fe、Ca元素濃度有少許升高,具有良好穩(wěn)定性,不會(huì)對(duì)土壤造成重金屬二次污染。焙燒后赤泥具有一定抗摩擦、沖擊等應(yīng)力能力,可回收重復(fù)使用,在處理PCBs土壤方面有著一定的應(yīng)用前景。
[Abstract]:Thermal catalytic dechlorination has many advantages such as low cost, high efficiency, safety and so on. The degradation of chlorinated aromatic compounds has been paid more and more attention by many scholars. In this paper, Fe _ 2O _ 3 and Fe _ 2O _ 3 Fe-Al composite oxides and three kinds of metal oxides of red mud were selected as catalysts, and PCB30 in soil was used as the treatment object to study the degradation effect of the above three kinds of metal oxides on polychlorinated biphenyls (PCBs). Various factors affecting the catalytic effect of Fe _ 2O _ 3 were discussed, and the conditions of Fe _ 2O _ 3 degradation of PCB30 were optimized by central response surface analysis. The catalytic efficiency of Fe-Al composite oxides under different conditions, such as different ratio and dosage of Fe-Al composite oxides, preparation of Bi-modified red mud particles and its catalytic degradation effect on PCB30 in soil were investigated, and the treatment conditions were optimized. The effect of red mud particles as catalyst on soil was studied by repeated reuse test. The degradation effect of PCB30 in soil was investigated by CCD central response surface analysis (CCD-RSM), and the results showed that the degradation effect of PCB30 in soil under the catalysis of Fe _ 2O _ 3 was found by the method of CCD central response surface analysis. The optimum catalytic conditions are as follows: the amount of catalyst is 0.23 g, the reaction temperature is 333.33 鈩，

本文編號(hào)：1992245