Modification of porous stainless steel hollow fibers by adding TiO2, ZrO2 and SiO2 nano-particles

Using 316L stainless steel powder (SSP) with a nominal particle size of 25 μm, porous stainless steel hollow fibers (SSHFs) have been prepared via dry-wet spinning of a particle-loaded casting solution based on non-solvent induced phase inversion, followed by temperature programming sintering. The morphology and performances were characterized by the maximum/mean pore size, SEM, porosity, density, shrinkage, pure water flux and mechanical strength. Subsequently, SSHFs were modified by adding TiO2, ZrO2 and SiO2 nano-particles for the first time. The morphology of SSHFs relied on not only the SSP contents, but also the contents of TiO2, ZrO2 and SiO2 nano-particles. The corresponding results demonstrated that SSHFs with TiO2 nano-particles possessed excellent properties, especially for mechanical strength having a more than 100 % increase and a maximum pore size of 4.5 μm. What’s more, nano-particles also reduced the defects of SSHFs’ structure, which could be observed from SEM images.