Stabilization of heavy metal cations in the framework of zirconium phosphates

Coordination forms of heavy metal cations (such as Pt, Mo and W) in the fra mework of zirconium phosphates and their influence on the matrix structure were studied by the EXAFS method. Additional stabilizing cations (La and Si in our case) are usually located in the structure of zirconium phosphates. It is shown that the basic sites of cation stabilization in the framework of zirconium phosphates are the positions of the second cations. Oxide part icles MeOx can grow at such sites if the sorption capacity of zirconium pho sphates is not enough for stabilization of the entire amount of heavy metal cations. (C) 2001 Elsevier Science B.V. All rights reserved.