Light scattering studies to determine molecular weight of freshly prepared Zr(IV) hydrous polymer

In the present work, Zr(IV) has been taken as a homologue for Pu(IV) in order to study the behaviour of Pu in aqueous systems. The direct detection of polymerization of tetravalent zirconium and determination of molecular weight of freshly prepared Zr(IV) polymer was performed by using dynamic light scattering device. Experiments were conducted at 4 different concentrations of zirconium prepared in 1 M nitric acid at 298 K. Particle diameter d 50 was estimated as 255 nm. Differential refractive index increment was also measured. The molecular weight of freshly prepared Zr(IV) polymer was determined as 1,610 Da and second virial coefficient A2 -0.0106 ml g-1 Da by using Debye plot showing that Zr(IV) can undergo hydrolysis even under strongly acidic conditions leading to the formation of high molecular weight hydrated polymers. (author)