Patent ID: 8663479

Claim:
A method for removing a target contaminant from an aqueous medium comprising a first amount of said target contaminant, said method comprising: providing a composition comprising an underloaded transition metal-loaded natural zeolite having a concentration between 0.05 and 0.2 milliequivalents transition metal per gram of natural zeolite, wherein said aqueous medium comprises a first amount of said target contaminant; and contacting said aqueous medium with said underloaded transition metal-loaded zeolite to form treated aqueous medium; wherein said underloaded transition metal-loaded zeolite reduces the amount of target contaminant in said aqueous medium, and wherein said treated aqueous medium comprises a second amount of said target contaminant lower than said first amount, and wherein said natural zeolite is loaded with a minimum amount of transition metal ions needed to stabilize intrinsic arsenic on the natural zeolite and limit leaching of the intrinsic arsenic from the natural zeolite while maximizing the capacity of the zeolite for the target contaminant, and wherein the target contaminant is cationic.