| 摘要 |
Ion exchange resin particles bearing ion exchange groups only in the most accessible portions of the particles possess kinetic advantages over fully functionalized resins in continuous-flow treatment of fluids. Resin beads are functionalized in an outer region that is from 32 to 73% of the bead radius thick: non-spherical or macroporous particles are similarly functionalized in a layer that is adjacent to the outer surface of the particle or to the surface of the macropores. Such a functionalization is obtained using a reagent system in which the functionalization rate is faster than the rate of diffusion of the reagent into the particle, and stopping the reaction when from 68% to 98% of the most readily accessible, functionalizable sites are functionalized. |
