Phosphorus removal from wastewater by ionic exchange using a surface-modified Al alloy filter

In this study, a cost-effective and eco-friendly route for removal of phosphate in wastewater was demonstrated using an Al alloy foam filter with a mesoporous aluminum hydroxide (Al(OH3) film. The mesoporous Al(OH)3 film on which the ion exchange and adsorption of phosphate occur was generated using a simple alkali surface modification process. For higher phosphate removal by the surface-modified Al alloy foam filter, the number of filters was increased up to 20, which achieved 90% phosphate removal within a very short contact time. As a recycling process, a second alkali surface modification was applied to the used filter after phosphate adsorption. It clearly indicated that the used filter can be recycled via a second alkali surface modification due to the ion exchange mechanism. It was shown that an alkali surface-modified Al alloy foam filter is a powerful candidate for phosphate removal in water treatment facilities.