Abstract: A method of treating water to remove selenium and/or mercury that is dissolved in the water. The method includes adding an acid to the water to reduce the pH, adding a metal reagent to the water that is effective to reduce the selenium and/or mercury to a lower oxidation state, and then removing the reduced selenium and/or mercury from the water.

Abstract: Methods for treating water containing a target anion to remove the target anion can include preparing a treatment composition solution that contains a metal treatment agent, adjusting the treatment composition solution to a first pH that is alkaline and then to a second pH that is acidic, and contacting the treatment composition solution with the water that contains the target anion.

Abstract: Methods are disclosed for treating water containing a target anion to remove the target anion. The methods can include preparing a treatment composition solution that contains a metal treatment agent, adjusting the treatment composition solution to a first pH that is alkaline and then to a second pH that is acidic, and contacting the treatment composition solution with the water that contains the target anion.

Abstract: Methods for removing a target selenium entity from fluids by treating the fluid with a rare earth impregnated media containing an immobilized rare earth. The methods including obtaining a contaminated fluid comprising water and dissolved selenate; contacting the feed fluid with a rare earth impregnated media for removal of at least a portion of the selenate from the feed fluid thereby forming a treated fluid comprising less selenium than the feed fluid.

Abstract: A method for treating water to remove a target analyte that includes adding to the water a rare earth metal salt and a coagulant, and then removing the target analyte from the water. The treatment composition can be added as a blend that includes die coagulant and the rare earth metal salt.

Abstract: Methods for removing a target selenium entity from fluids by treating the fluid with a rare earth impregnated media containing an immobilized rare earth. The methods including obtaining a contaminated fluid comprising water and dissolved selenate; contacting the feed fluid with a rare earth impregnated media for removal of at least a portion of the selenate from the feed fluid thereby forming a treated fluid comprising less selenium than the feed fluid.

Abstract: Methods for removing a target anion entity, such as a phosphate ion, from fluids by treating the fluid with a substrate containing an immobilized rare earth, the substrate being either a first loaded substrate including a first immobilized cationic rare earth, the first loaded substrate being formed by precipitating a rare earth in a clay such that the rare earth is fixed inside a porous structure of the clay and/or fixed on the surface of the clay; or a second loaded substrate comprising a second immobilized cationic rare earth that is bonded to the second loaded substrate via a chelating ligand.

Abstract: Disclosed is a method for inhibiting the formation of foam in aqueous systems by adding foam control composition including a polyoxyethylene and/or a polyoxypropylene nonionic fatty acid derivative and a quaternary ammonium surfactant.

Abstract: Methods for removing a target anion entity, such as a phosphate ion, from fluids by treating the fluid with a substrate containing an immobilized rare earth, the substrate being either a first loaded substrate including a first immobilized cationic rare earth, the first loaded substrate being formed by precipitating a rare earth in a clay such that the rare earth is fixed inside a porous structure of the clay and/or fixed on the surface of the clay; or a second loaded substrate comprising a second immobilized cationic rare earth that is bonded to the second loaded substrate via a chelating ligand.

Abstract: Disclosed is a method for inhibiting the formation of foam in aqueous systems by adding foam control composition including a polyoxethylene and/or a polyoxypropylene nonionic fatty acid derivative and a quaternary ammonium surfactant.