DOWEX Resins for Separation of Phosphorus from Liquid Media

Phosphorus - P Phosphorus is found in many ionic forms. Some of the common ionic forms of phosphate are the oxidized species of phosphoric acid (H3PO4), phosphorous acid (H2PO3), and hypophosphorous acid (H3PO2), along with their salts.

Applications

Water / Waste Water: The oxidized phosphates are anions so they can be removed from solutions with anion exchange resins. If phosphates are present as acids, they can be removed with an acid absorber like DOWEX™ M-43 anion exchange resin. When they are present as acid salts, a strong base anion resin like DOWEX 21K XLT resin is recommended. Phosphates generally have a low affinity for Type II strong base anion exchange resins so they are typically not used. For streams that have a high organic content and are prone to surface fouling, DOWEX MARATHON™ MSA resin is recommended. Unfortunately, phosphates are very weakly selected so resin capacity will be limited in the presence of most other anions. See table of selectivity data (24K PDF).

Selective Removal: Phosphates can be selectively removed from solution with the chelating resin DOWEX M4195 resin in the copper form. (1, 2)

Phosphate Ester Lubricants: Phosphate esters are used as lubricants for a variety of industrial applications. During the course of their use, these lubricants break down and release phosphates that can be detrimental to the equipment and operations. DOWEX M-43 resin effectively removes the phosphate and many metals from the lubricant. DOWEX M-43 anion exchange resins must be used in the dry form to optimize performance. (3)

A wide variety of organo-phosphorous compounds also exist that may or may not be ionic. When the organic group is small, anion exchange resins will work best. When the organic group is large, an adsorption approach may work best. For more information, please go to Organic Removal From Process Streams.

Product	Description	Type	Matrix	Total Exchange Capacity* eq/l (kgr/ft3)	Available Forms
DOWEX 21K XLT	Uniform particle size, high capacity, strong base anion exchange resin for mineral processing applications.	Type I Strong Base Anion	Styrene-DVB, Gel	1.4	Cl-
DOWEX MARATHON MSA	Uniform particle size, high capacity, macroporous strong base anion exchange resin for water demineralization applications.	Type I Strong Base Anion	Styrene-DVB, Macroporous	1.1 (24.0)	Cl-
DOWEX M-43	Corrosion control with DOWEX M-43 ion exchange resin.	Weak Base Anion	Styrene-DVB, Macroporous	1.55	FB (Free Base) form
DOWEX M4195	Chelating resin for copper, nickel, and cobalt processing.	Chelating Resin	Styrene-DVB, Macroporous		Bis-Picolylamine

References 1. "Selective removal and recovery of phosphate using a new class of sorbents" Water Science Tech. Vol. 33 1996 Department of Civil and Environmental Engineering 13E Packer Avenue, Lehigh University, Bethlehem, PA 18015, U.S.A. Dongye Zhao and Arup K. Sengupta. 2. "Ultimate removal of phosphate from wastewater using a new class of polymeric ion exchangers." Zhao, Dongye; Sengupta, Arup K.. Dep. of Civil and Environmental Engineering, Lehigh University, Bethlehem, PA, USA. Water Res. (1998), 32(5), 1613-1625. 3. "Regeneration of Phospahte Ester Lubricating Fluids" Peter Dufresne, US Patent 5,661,117 August 26, 1997.