Abstract: The present invention is directed to the removal of one or more selected target materials, in particular a physiologically active compound contaminant, from various streams using a rare earth fixing agent.

Abstract: A method and apparatus for separating arsenic from an aqueous solution containing arsenic. The method includes the steps of contacting an arsenic-containing solution with a first portion of fixing agent to remove at least a portion of the arsenic. An arsenic-laden fixing agent is separated from the solution and the partially depleted solution is contacted with a second portion of fixing agent. The fixing agent can include a high surface area insoluble compound containing one or more of cerium, lanthanum, or praseodymium. Following removal of the arsenic, the arsenic-depleted solution can be further processed to separate a recoverable metal through metal refining. The arsenic-laden fixing agent can be filtered to recover and recycle a filtrate to the solution for additional treatment, as well as using a partially saturated fixing agent to remove arsenic from fresh solution.

Abstract: A method and apparatus for removing arsenic from an arsenic-bearing material. The method includes the steps of contracting an arsenic-bearing material with an arsenic leaching agent to form an arsenic-containing solution and arsenic-depleted solids. The leaching agent can be an inorganic salt, an inorganic acid, an organic acid, and/or an alkaline agent. The arsenic-depleted solids are separated from the arsenic-containing solution, which is contacted with a fixing agent 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 then separated from the arsenic-depleted solution. A recoverable metal in the arsenic-depleted solids, arsenic-containing solution or arsenic-depleted solution can be separated and recovered. Recoverable metals can include metal from Group IA, Group IIA, Group VIII and the transition metals.

Abstract: 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.

Abstract: The subject invention relates generally to friable metal oxide agglomerates and specifically to agglomerates containing high surface area rare earth-containing materials and a polymeric binder.

Abstract: Embodiments are provided for removing a variety of contaminants using both rare earth and non-rare earth-containing treatment elements.

Abstract: The present invention is directed to the removal of one or more selected target materials, in particular a physiologically active compound contaminant, from various streams using a rare earth fixing agent.

Abstract: The invention relates generally to a process for removing one or more contaminants from an electrolytic solution and more particularly to a process for removing the one or more contaminants contained in an electrorefining solution using rare earth metals.

Abstract: The invention is directed generally to a porous and durable ceramic filter monolith coated with one or more rare earth-containing compositions for removing contaminants from a fluid, particularly for removing one or more contaminants from water.