【作者】 周超强；

【导师】 龚凡；

【作者基本信息】 哈尔滨工程大学 ， 应用化学， 2009， 硕士

【摘要】 本文以堇青石蜂窝陶瓷和TiO2为载体,通过溶胶-凝胶法和浆料涂敷法制备了整体式铜锰复合催化剂；在不同制备工艺中探讨了Cu、Mn相对含量对催化剂脱硝性能的影响；并找出了各制备方法中Cu、Mn的负载方式对复合催化剂脱硝性能的影响。结合BET、XRD、XPS、SEM及H2-TPR等测试手段,探讨了各种制备方法下催化剂的各物化参数与其脱硝活性的关系。用溶胶-凝胶法制备铜锰复合催化剂时,从探讨单活性组分催化剂的制备出发,得到了Mn和Cu的最佳负载量。再以两种活性组分负载方式制备了Mn、Cu复合催化剂。通过交替负载最佳Mn含量和Cu含量的Mn-Ce-O/TiO2和Cu-Ce-O/TiO2活性层,制备了Mn、Cu分层负载的复合催化剂；活性测试表明,催化剂的脱硝性能随着两活性层相对质量不同而变化,当催化剂上两活性层质量比为1：1时,复合催化剂在200-350℃的脱硝效率高于75%,相对于含锰单活性组分的催化剂,其高活性温度窗口有较显著拓宽。向钛溶胶同时加入Mn和Cu活性组分制备的复合催化剂中,以摩尔比Mn/Ti及Cu/Ti为0.3和0.1引入活性组分时得到的催化剂在低温的脱硝性能得到促进,最高脱硝效率达到87%,但是温度窗口没有明显的拓宽,当加入Cu和Mn的量相同时得到的催化剂脱硝性能很差。用浆料涂敷法制备复合催化剂时,配制浆料时同时添加Mn和Cu的量分别为所添加TiO2粉末质量的15%和5%时得到的催化剂活性最佳,相对于同方法制备的Mn单活性组分催化剂,此复合催化剂有更高的脱硝转化率,而加入的Mn、Cu量相当时催化剂活性反而降低。将Mn和Cu以MnOx/TiO2及CuOx/TiO2形式在浆料制备时加入,当加入的两种粉末质量为2：1时得到的复合催化剂活性最佳,活性温度窗口得到拓宽。通过对比四种制备方法下得到的最佳铜锰复合催化剂的活性及各表征结果可知,各催化剂上Mn均以高活性的MnO2形式存在,TiO2以锐钛矿型存在,活性组分在上面均匀分布,各催化剂都有较大的比表面积和孔容,这些是催化剂较好脱硝活性表现的原因。而H2-TPR测试结果则说明Cu、Mn的不同引入方法影响两活性组分间的相互作用,当Cu、Mn以混合溶液同时引入时,催化剂上Cu、Mn间相互作用强,当一种活性组分含量占主导地位时,相对于其单活性组分催化剂,能得到更高的最高脱硝效率；而两种活性组分分别负载在不同载体上,再在基体上复合时,催化剂上Cu、Mn间相互作用小,得到复合催化剂在更宽温度范围有较高脱硝效率。更多还原

【Abstract】 Using cordierite ceramic honeycomb and TiO2 as the support, monolithic catalysts contain Cu-Mn bimetallic oxides were prepared by sol-gel and slurry coating method. In different preparing processes, the relationship between relative proportion of Cu, Mn and the resulted DeNOx performance was discussed. The ways of introducing Mn and Cu and their effect on the resulted catalytic activity is also studied. A comparison was made between the different catalysts based on the results of activity test and X-ray diffraction, BET-surface area, temperature-programmed reduction (TPR), and X-ray photoelectron spectroscopy (XPS) techniques characterization.The research started from the preparation of the catalyst containing single active component by sol-gel method. The best Cu, Mn loading was gained respectively. Catalysts loaded with Cu-Mn bimetallic oxides were prepared by two ways:Impregnated by turns in the titanium sol contained Mn or Cu, two kinds of active phase were loaded onto the cordierite ceramic honeycomb. As the mass of the two active layer varied, a series of catalysts with different DeNOx activity were prepared, when the two active layer mass ratio was 1:1, the composite catalyst had a high DeNOx of 75% between the temperature window of 200-350℃. By adding Mn and Cu into the same titanium sol, the composite catalysts were prepared in another way. When added with the molar ratio of Mn/Ti(0.3) and Cu/Ti(0.1), respectively, the prepared catalyst has the best DeNOx activity. Its highest NO conversion reached up to 87%, However, there was no improvement in an obvious wider temperature window.Composite catalysts were also Prepared by slurry coating method, Mn and Cu were added into the slurry at the same time, the best catalyst was prepared by controlling the quantity of added Mn and Cu, when the added Mn and Cu were 15% and 5% according to the added TiO2, Compared with the catalyst contain Mn as the only active component, the activity of this complex catalyst has higher conversion rate of NO. While a considerable amount of Cu and Mn is added, the prepared catalyst has the worst performance. In another method, Mn and Cu were loaded onto the catalyst by adding MnOx/TiO2 and CuOx/TiO2 powder into the slurry. The complex catalyst showed a high activity between a wider temperature window as the two kinds of powder were added with a mass ratio of 2:1.The best catalysts prepared in the four process were sorted out for comparation based on their activity test and various characterization results, it is found that Mn exists on the catalyst in high active form of MnO2, and TiO2 exists in the form of Anatase, catalyst has larger surface area and pore volume, active component is distributed uniformly in amorphous form. All of these were the reason for the considerable DeNOx of the four catalysts. The H2-TPR characterization revealed that the interaction between Cu and Mn varied as the introduction of these two component changed. When introduced as a mixed solution, Cu, Mn on the prepared catalysts interact with each other strongly. When one of the active components has a dominant content, according to its single-component catalyst, the catalyst has higher maximum denitrification. When this two active component were firstly loaded onto different supports, the gained active supports were assembled on the ceramic. The resulted composite catalyst acted effectively in a broader temperature scope.更多还原