Method and apparatus for recovering a metal and seperating arsenic from an arsenic containing solution

A method and apparatus for recovering a metal and separating arsenic from an arsenic-containing solution. The method includes contacting the arsenic-containing solution with a fixing agent that comprises a rare earth compound to produce an arsenic-depleted solution and an arsenic-laden fixing agent. The fixing agent comprises a rare earth-containing compound that can include cerium, lanthanum, or praseodymium. The fixing agent is separated from the arsenic-depleted solution and a recoverable metal is separated from one or more of the arsenic-containing solution and the arsenic-depleted solution. Recoverable metals can include metal from Group IA, Group IIA, Group VIII and the transition metals. The arsenic-containing solution can be formed by contacting an arsenic-containing material with a leaching agent. Arsenic-depleted solids formed during the leach can also be separated and recovered. An apparatus of the invention can include two or more arsenic fixing units configured to conduct the method on a continuous basis.