Separation of titanium dioxide photocatalyst in its aqueous suspensions by coagulation with basic aluminium chloride

A coagulation technique was applied to separate titanium dioxide photocatalyst in its aqueous suspensions after the photocatalyzed degradation of organic contaminants. When a basic aluminium chloride was used as a coagulating agent, titanium dioxide was flocculated and sedimented rapidly; the supernatant solution was practically transparent. After the coagulation with basic aluminium chloride, the titanium dioxide separated from the mother liquor could be satisfactorily reused as a photocatalyst by several simple treatments.