本文選題：銅鈰氧化物　切入點(diǎn)：玻璃纖維　出處：《中北大學(xué)》2017年碩士論文

【摘要】：揮發(fā)性有機(jī)化合物作為一類主要的大氣污染物,受到了廣泛關(guān)注。催化燃燒因其效率高、能耗低,成為處理VOCs的有效方法之一。相比于貴金屬催化劑,過渡金屬催化劑成本低、穩(wěn)定性好,具有很大的競爭力。本論文以玻纖蜂窩為載體,以CuO為活性組分,考察了活性組分負(fù)載量、煅燒溫度、Cu/(Cu+Ce)摩爾比、絡(luò)合劑對玻纖蜂窩催化劑催化燃燒VOCs活性的影響。通過BET、XRD、H2-TPR、NH3-TPD、VOCs-TPD等手段對催化劑進(jìn)行表征,探討了催化劑表面性質(zhì)與催化劑活性之間的聯(lián)系。首先采用等體積浸漬法,通過改變CuO擔(dān)載量分別為8%、10%、12%,改變煅燒溫度分別為500℃、600℃、700℃,制備了Cu/Al_2O_3-M玻纖整體式催化劑,通過對乙酸乙酯的催化燃燒實驗考察了其催化性能。結(jié)果顯示負(fù)載量為10%,煅燒溫度為600℃的Cu10/Al_2O_3-M-600玻纖整體式催化劑催化活性最佳。采用共浸漬法通過改變Cu/(Cu+Ce)摩爾比分別為1、0.67、0.5、0.33、0.2、0,制備了一系列CuCe玻纖整體式催化劑,通過乙酸乙酯、異丙醇及甲苯的催化燃燒實驗考察了催化活性。結(jié)果顯示摻雜CeO2可以提高CuxCe1-x/Al_2O_3-M催化劑的催化活性,Cu_(0.5)Ce_(0.5)/Al_2O_3-M對異丙醇與乙酸乙酯催化活性最高,325℃時轉(zhuǎn)化率即可達(dá)到100%。表征結(jié)果顯示在CuxCe1-x/Al_2O_3-M玻纖催化劑中氧化銅以高分散態(tài)存在而氧化鈰則是以小的納米晶粒狀態(tài)存在,而且納米氧化鈰顆粒尺寸隨著Cu/(Cu+Ce)摩爾比的減小而增大。加入CeO2會降低活性氧的含量、減弱催化劑的還原性,同時提高催化劑表面總酸位的數(shù)量,特別是路易斯酸位的量,進(jìn)而影響乙酸乙酯和異丙醇的吸附量。對活性最佳的Cu_(0.5)Ce_(0.5)/Al_2O_3-M玻纖整體式催化劑進(jìn)行50h穩(wěn)定性測試,結(jié)果顯示,在325℃乙酸乙酯空速為20000h-1時,催化劑活性能保持97%以上。在性能最優(yōu)的Cu_(0.5)Ce_(0.5)/Al_2O_3-M玻纖催化劑中添加酸性絡(luò)合劑(蘋果酸、檸檬酸、乳酸)和堿性絡(luò)合劑(二乙烯三胺、三乙烯四胺、烏洛托品),考察絡(luò)合劑對Cu_(0.5)Ce_(0.5)/Al_2O_3-M玻纖催化劑催化燃燒乙酸乙酯性能影響。結(jié)果顯示,絡(luò)合劑添加并沒有提高催化劑活性。添加酸性絡(luò)合劑增加了布朗酸位,但是對路易斯酸位并沒有貢獻(xiàn),相應(yīng)的也就沒有增加乙酸乙酯化學(xué)吸附量;堿性絡(luò)合劑加入,可以提高催化劑還原能力,但是降低了催化劑路易斯酸位以及總酸位的數(shù)量,降低了乙酸乙酯化學(xué)吸附量,共同作用導(dǎo)致催化劑活性減弱。Cux Ce1-x/Al_2O_3-M催化劑催化燃燒過程遵循Mars-van Krevelen規(guī)則,即催化活性由催化劑氧化還原能力與吸附能力共同影響。
[Abstract]:Volatile organic compounds (VOCs), as one of the major atmospheric pollutants, have attracted wide attention. Catalytic combustion has become one of the effective methods for VOCs treatment because of its high efficiency and low energy consumption. Compared with noble metal catalysts, transition metal catalysts have low cost. In this paper, glass fiber honeycomb was used as carrier and CuO as active component. The influence of the complexing agent on the catalytic combustion activity of glass fiber honeycomb catalyst was studied. The catalyst was characterized by BET-XRDX H2-TPRN NH3-TPD-VOCs-TPD, and the relationship between the surface properties of the catalyst and the activity of the catalyst was discussed. Firstly, the isovolumetric impregnation method was used to investigate the relationship between the surface properties of the catalyst and the activity of the catalyst. The Cu/Al_2O_3-M glass fiber monolithic catalyst was prepared by changing the loading capacity of CuO from 8 to 10 and calcining at 500 鈩，

本文編號：1669729