稻壳灰制备TiO_2-SiO_2复合载体脱硝催化材料

Preparation of Denitrification Catalytic Materials Using TiO_2-SiO_2 Composites as Carrier by Rice Husk Ash

鉴于农业废弃物稻壳灰中非晶态硅含量高的特点,以稻壳灰为原料,采用共沉淀法制备了以TiO_2-SiO_2复合材料为载体,锰、铈为活性组分的脱硝催化材料。探究了SiO_2的添加对催化材料微观结构的影响,并对不同硅含量催化材料的脱硝机理进行了相关分析。实验结果表明,与纯TiO_2为载体的催化材料相比,TiO_2-SiO_2复合材料为载体的催化材料表面颗粒大小均匀,呈蓬松状态堆积,比表面积及孔容都有所增加,弱酸性位点的数量也大大增加,当SiO_2与TiO_2的物质的量比为4∶1时,催化材料的脱硝效率可达90%以上。

In view of the high content of amorphous silicon in the rice husk ash of agricultural waste, this paper used the rice husk ash as the raw material to prepare the denitrification catalytic materials with the TiO 2-SiO 2 composites as the carrier and the manganese, cerium as the active component. The influence of SiO 2 addition on the microstructure of catalytic materials was investigated, and the denitrification mechanism of catalytic materials with different silicon content was analyzed. The experimental results showed that,compared with the catalytic materials with pure TiO 2 as the carrier, the particle size of the catalyst materials with TiO 2-SiO 2 composites as the carrier is uniform and piling up in a fluffy state. The specific surface area and pore volume of catalytic mate- rials have increased, and the number of weak acid sites has also been greatly improved. When the molar ratio of silicon to titanium is 4 ∶1, the denitration efficiency can reach more than 90%.