Al_2O_3负载型Cu-Al类水滑石氧化物的NO_x吸附及分解性能

Performance of Al_2O_3 loaded Cu-Al hydrotalcite-like oxides in adsorption and decomposition of NO_x

采用水热法制备铜铝水滑石作为前体,经500℃焙烧得到Cu-Al复合氧化物,并利用X射线衍射、红外光谱对其进行表征;将Cu-Al复合氧化物负载于直径为3～5 mm球状Al_2O_3载体上,进行NO吸附和热稳定性试验。结果表明,NO、O_2、H_2O(g)在Cu-Al复合氧化物作用下在氧化物表面生成HNO3,并与Cu-Al复合氧化物中的CuO组分反应生成Cu(NO_3)_2,吸附率可达28%,再高温焙烧可以释放以NO为主体的氮氧化物,并且可以恢复到之前的金属氧化物结构。而吸附完成的化合物静置数天后会回到原来的水滑石层状结构。

Copper-aluminum hydrotalcite is made via hydrothermal method,then is roasted at 500℃to prepare CuAl complex oxides that is characterized by X-ray diffraction and infrared-red spectrum.The prepared Cu-Al composite oxide is loaded onto the surface of spherical Al2O3 carrier with a diameter between 3 mm and 5 mm,and the sample is evaluated in the experiments about NO adsorption and heat endurance.The experimental results show that NO,O2 and water steam forms HNO3 on the surface of Cu-Al complex oxides,then HNO3 reacts with Cu O in Cu-Al composite oxides to form Cu(NO3)2,and the adsorption efficiency can reach 28%.NOx,with NO as the main body,can be released when the product is roasted at a high temperature,and the structure of the former metal oxides can be restored.The adsorbed compounds will return to the original hydrotalcite-like layered structure after a few days of static storage.