Selective adsorption of lead (II) ions by a manganese dioxides-loaded adsorption resin

摘要

A new adsorbent SD300-M was successfully synthesized by coating the adsorption resin SD300 with manganese oxide via KMnO4 modification. The results of X-ray photoelectron spectrometer and nitrogen adsorption measurement revealed that the manganese oxide exists as MnO2 on the surface and inside the channel of the SD300 resin. The SD300-M resin exhibited higher adsorption capacity to Pb2+ with the maximum adsorption capacity as high as 141mg/g, comparing with original SD300 resin and the other manganese oxide-modified adsorbents, such as cellulose or carbon nanotubes. The increased adsorption of Pb2+ on the SD300-M resin arose mainly from the formation of inner-sphere complexes with MnO2. In the presence of Ca2+ and Mg2+, the SD300-M resin also has excellent adsorption selectivity for Pb2+ relative to that of the D301-M and HMO-001 resins, which arises from electrostatic interaction and surface complexation acting together. All the results indicate that the SD300-M resin is an efficient adsorbent to remove Pb2+ from aqueous solution.