COMPOSITE CATION EXCHANGERS

Sulfonated phenol formaldehyde resins containing different amounts of sulfonated sawdust were prepared. The thermal and chemical stabilities, scientific weight capacity, and apparent capacities for the exchange of Na+, Ca2+, and Mg2+ at different concentrations were detemined for both H+ and Na+ forms of resins. Composites containing up to 30%–50% of sawdust, while being very much cheaper, are comparable in their properties to the pure polymeric resin. Thus, cheaper exchangers can be prepared by substituting part of the polymer by sawdust. Copyright © 1979 John Wiley & Sons, Inc.