Process for the alkaline saponification of crosslinked acrylonitrile bead polymers

• Main Authors: SEIDEL RUDIGER, HAPP MICHAEL, ZARGES WOLFGANG, PODSZUN WOLFGANG, IRMSCHER DIETER
• Format: Patent
• Language: English
• Published: 23.01.2007
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR PREPARATION OR CHEMICAL WORKING-UP; THEIR RELEVANT APPARATUS; TRANSPORTING

The alkaline saponification of acrylonitrile bead polymers provides weakly acidic cation exchangers with little intrinsic color and with reduced residual nitrogen content if the saponification is begun at a temperature T 1 of from 70 to 120° C. and, once a degree of saponification of at least 65% has been reached, is completed at a temperature T 2 of from 120 to 180° C.