Wei Tianqi, Zhong Xin, Chen Xionggang, Guo Zhiguang
School of Materials Science and Engineering, Hubei University, Wuhan 430062, China.
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China.
Langmuir. 2025 Jul 1;41(25):16139-16149. doi: 10.1021/acs.langmuir.5c01225. Epub 2025 Jun 20.
The ceramic membrane with chemical, thermal, and mechanical stability is expected to realize oil-in-water (O/W) emulsion separation with high efficiency. A simple and cost-effective approach was adopted to fabricate a three-dimensional (3D) silica porous ceramic ultrafiltration membrane, leveraging diatomite as an abundant and economical mineral resource. A porous structure with high porosity and good mechanical properties was prepared by a sacrificial template method. Recognizing the distinct composition of ceramic powders, appropriate additives were carefully selected. By systematically adjusting parameters such as plasticizer and flux content, molding pressure, and holding time, the formation and distribution of the porous ceramic structure were effectively optimized. It was demonstrated that this method not only enabled the tunable pore size of the porous ceramic but also achieved a balance between its porosity and mechanical properties. The porous ceramic exhibited an average pore size of 6.48 nm, a porosity of 62.24%, water absorption of 70.6%, and a compressive strength of 10 MPa. These properties were achieved under fabrication conditions of 5 MPa molding pressure and 20 s dwell time, with the addition of 15% plasticizer (the mixture of poly(vinyl acetate) and ethylene glycol) and 10% flux (sodium silicate). The silica porous ceramic ultrafiltration membrane showed excellent performance in oil-water separation due to its hierarchically interconnected mesopores and strong water absorption, suitable for an O/W emulsion of 26,378 ppm high-concentration toluene and silicone oil. The separation efficiency reached up to 99.6%, with a flux as high as ∼1530 L m h bar. Furthermore, the ceramic membrane demonstrated excellent durability, maintaining a stable performance over 50 consecutive filtration cycles. This work provides new insights into the construction of an advanced porous ceramic ultrafiltration membrane for the efficient removal of water from oil products.
具有化学、热和机械稳定性的陶瓷膜有望实现高效的水包油（O/W）乳液分离。采用一种简单且经济高效的方法制备了三维（3D）二氧化硅多孔陶瓷超滤膜，利用硅藻土作为丰富且经济的矿物资源。通过牺牲模板法制备了具有高孔隙率和良好机械性能的多孔结构。认识到陶瓷粉末的不同组成，仔细选择了合适的添加剂。通过系统地调整增塑剂和助熔剂含量、成型压力和保压时间等参数，有效地优化了多孔陶瓷结构的形成和分布。结果表明，该方法不仅能使多孔陶瓷的孔径可调，还能在其孔隙率和机械性能之间实现平衡。该多孔陶瓷的平均孔径为6.48nm，孔隙率为62.24%，吸水率为70.6%，抗压强度为10MPa。这些性能是在5MPa成型压力和20s保压时间的制备条件下实现的，添加了15%的增塑剂（聚醋酸乙烯酯和乙二醇的混合物）和10%的助熔剂（硅酸钠）。二氧化硅多孔陶瓷超滤膜由于其分级互连的中孔和强吸水性而在油水分离中表现出优异的性能，适用于26378ppm高浓度甲苯和硅油的O/W乳液。分离效率高达99.6%，通量高达约1530L m h bar。此外，该陶瓷膜表现出优异的耐久性，在连续50个过滤循环中保持稳定性能。这项工作为构建用于从油品中高效去除水分的先进多孔陶瓷超滤膜提供了新的见解。
