Silica-Based Hollow Fiber Membrane for Water Treatment

This chapter describes the application of silica-based hollow fiber membrane for water treatment. There are two types of common hollow fiber membrane for water treatment: polymer and ceramic membrane. A well-known phase inversion method was used to prepare these membranes. Accordingly, silica (SiO2) is a well-known glass forming oxide, which can be microporous, mesoporous, and macroporous material. In membrane technology, SiO2 plays an important role in enhancement of the membrane properties as well as performance. For example, addition of silica in polymer membrane matrix could induce higher hydrophilicity behavior, thus increasing membrane flux. However, in terms of geometry, polymer hollow fiber membrane is rarely studied as it offers some drawback. Alternatively, silica-based ceramic hollow fiber membrane has been successfully fabricated from cheap materials such as clays and waste ashes. This kind of technology offers advantages in water treatment as it could not only be used for separation only, but combined separation-absorption application for water treatment like heavy metal removal. Finally, some case studies in water treatment (i.e., oily wastewater separation) are discussed, with potentialities, drawbacks, and future trends.