Adsorption of Phosphate from Aqueous Solution with Blast Furnace Slag Activated by Hydrated Lime as Sorbent

This paper describes a method of removing phosphate (P) from aqueous solution by sorbent prepared with amorphous blast furnace slag (BFS) and hydrated lime. An orthogonal experiment was carried out to investigate the factors of hydration time, slurrying temperature and the weight ratio of blast furnace slag /hydrated lime and water/solid on the reactivity of the sorbent. Chemical composition of BFS was analyzed by atomic absorption spectrometry, microstructure and phase analysis of samples were conducted by SEM and XRD. It is found that all sorbents prepared show higher P adsorption capacity than single blast furnace slag.