NaA分子筛合成残余物掺杂制备SiC膜支撑体

Preparation of SiC membrane support by adding synthesis residues of NaA zeolite

选用平均粒径100μm碳化硅为主要原料粉体,NaA分子筛合成废液中提取的粉体(主要成分为NaA分子筛和微量硅铝钠化合物)为烧结助剂,采用挤出法进行生坯成型,最后通过原位烧结技术制备高温气体净化用的管式碳化硅膜支撑体(外径60 mm,内径40 mm,长1500 mm).研究结果表明,烧结助剂的最佳含量为质量分数3%,随着烧成温度的升高,碳化硅膜支撑体孔隙率逐渐减小,平均孔径也随之增加.当烧成温度达到1150℃时,膜支撑体平均孔径为30.92μm,气体通量为99.32 m 3/(m^2·h·kPa),抗弯强度达到29.50 MPa,同时也表现出优异的抗热震性能和耐酸腐蚀性能,为高温气体净化碳化硅膜的低成本、绿色化制备以及应用研究提供了理论依据.

In this paper,silicon carbid(d x=100μm)was used as the main raw material powder and the synthesis residues of NaA zeolite extracted from the waste liquid was used as sintering aid.Firstly,the green body was formed by extrusion,then the in-situ sintering technique was adopted to prepare the large pore size SiC ceramic support tube(Outer diameter is 60 mm,inner diameter is 40 mm,length is 1500 mm).The results showed that the optimum content of the sintering aid is 3%.As the temperature increases,the porosity of the SiC ceramic support decreases gradually and the average pore diameter increases.When the temperature was 1150℃,the average pore diameter of the support is 30.92μm and the distribution is very narrow,the gas flux was 99.32 m 3/(m^2·h·kPa)and the bending strength reaches a maximum value of 29.50 MPa,while the SiC ceramic support also exhibits excellent thermal shock resistance and acid corrosion resistance,providing a theoretical basis for the low-cost,green preparation and application research of silicon carbide membrane for hot gas filtration.