添加剂对粉煤灰基陶瓷膜支撑体性能的影响

Effect of additives on the performance of fly ash-based ceramic film supports

以粉煤灰为骨料,羧甲基纤维素(CMC)为黏结剂,分别选取聚甲基丙烯酸甲酯(PMMA)、CaCO_(3)、木炭粉为造孔剂,TiO_(2)、CaO、硼砂为烧结助剂,采用挤压成型法与固态粒子烧结法制备粉煤灰基陶瓷膜支撑体.考察造孔剂与烧结助剂的种类、添加量对粉煤灰基陶瓷膜支撑体性能的影响,并对膜的纯水通量、抗折强度、微观形貌、物质组成、孔隙率和酸碱腐蚀率等性能进行表征.结果表明:木炭粉为造孔剂,TiO_(2)为烧结助剂时,所制得的粉煤灰基陶瓷膜支撑体性能兼具良好的机械性能与透水性能.木炭粉最佳添加量为15%(质量分数),此时支撑体平均孔径为2.78μm,孔隙率为44.68%,纯水通量为3 280.04 L/(m^(2)·h·MPa),抗折强度为24.02 MPa,酸、碱腐蚀率分别为0.25%和0.22%.TiO_(2)最佳添加量为4%(质量分数),此时支撑体平均孔径为1.97μm,孔隙率为44.95%,纯水通量为3303.76L/(m^(2)·h·MPa),抗折强度为35.84 MPa,其酸、碱腐蚀率分别为0.32%和0.17%.

In this paper,to explore the influence of poreforming agents and sintering additives on the performance of the support body,fly ash was used as aggregate,carboxymethyl cellulose(CMC)as binder,polymethyl methacrylate(PMMA),CaCO_(3)and charcoal powder were selected as poreforming agents,TiO_(2),CaO and borax were used as sintering additives.Fly ash-based ceramic membrane supports were prepared by extrusion molding and sintering of solid particles at atmospheric pressure.Pure water flux,flexural strength,microstructure,material composition,porosity and acid-base corrosion rate were characterized.The results show that when the pore-forming agent and sintering auxiliaries are charcoal powder and TiO_(2),the properties of the fly ash-based ceramic membrane support body are better,which is helpful to the preparation of low-cost ceramic membrane.When the amount of charcoal powder is 15%,the average pore size of the support body is 2.78μm,the porosity is 44.68%,and the acid and alkali corrosion rates are 0.25% and 0.22%,respectively.When the TiOz addition amount is 4%,the average pore size of the support body is 1.97μm,the porosity is 44.95%,and the acid and alkali corrosion rates are 0.32% and 0.17%,respectively.