ZrO_2微粉添加量对高温气固分离用氧化铝陶瓷膜性能的影响

Effects of zirconia micro-powder additions on performance of alumina ceramic membrane for gas-solid separation

为了调控氧化铝陶瓷膜的孔径大小及分布,并提高其抗热震性能,在平均粒径为20μm的氧化铝粉中添加不同量的中位粒径为2μm的Zr O_2微粉(Zr O_2微粉分别占混合粉质量的0、10%、20%、30%、40%),再加入结合剂等,经配料、制浆、莫来石支撑体浸渍、110℃干燥和1 300℃保温2 h煅烧后,制成氧化铝陶瓷膜试样,研究了Zr O_2微粉加入量对陶瓷膜孔径大小、孔径分布、孔隙率、透气度和抗热震性的影响。结果表明:随着Zr O_2微粉加入量的增加,陶瓷膜的最可几孔径、孔隙率和透气度均逐渐减小,孔径分布变窄,抗热震性提高。在满足高温烟气气固分离使用要求的条件下,氧化铝粉中Zr O_2微粉加入量以20%(w)为宜。

Zirconia micro-powders with the median particle size of 2 nm were introduced into alumina pow-ders with the median particle size of 20 nm during the preparation of porous alumina ceramic membrane to adjust pore size and distribution of alumina ceramic membrane,and thus to improve its thermal shock re-sistance. The additions of zirconia micro-powders account for 0,10% ,20% ,30% and 40% of the total mass of zirconia and alumina powders,respectively. All the materials were mixed into slurries. The mullite sup-ports were impregnated by the slurry. After drying at 110 ℃ and soaking at 1 300 ℃ for 2 h,the alumina ce-ramic membrane specimens were obtained. The effects of zirconia powders additions on the pore size and distribution,porosity,air permeability and thermal shock resistance of alumina ceramic membrane were in-vestigated. The results show that,with the increase of the zirconia micro-powders addition,the most proba-ble pore size,porosity and gas permeability of ceramic membrane decrease,the pore size distribution be-comes narrow,and the thermal shock resistance increases. The optimum addition of zirconia micro-pow-ders is 20% on the premise of meeting the requirements of gas-solid separation of hot flue gas.