Remediation of radioiodine using polyamine anion exchange resins

Two weak base anion exchange resins, Lewatit A365 and Purolite MTS9850, have been tested for the removal of aqueous iodide from conditions simulating nuclear waste reprocessing streams. pH variation and relevant co-contaminant addition (nitrate, molybdate and iodine) allowed for assessment of iodide extraction behaviour of each resin. Isotherm experiments were performed and maximum uptake capacities obtained exceed current industrial adsorbents, such as silver-impregnated zeolites. Maximum loading capacities, determined by Dubinin–Radushkevich isotherm, were 761 ± 14 mg g−1 for MTS9850 and 589 ± 15 mg g−1 for A365. Uptake for both resins was significantly suppressed by nitrate and molybdate ions. The presence of dissolved iodine in the raffinate however, was found to increase iodide uptake. This was explained by characterisation of the spent resin surface by infrared and Raman spectroscopy, which determined the presence of triiodide, indicating charge-transfer complex formation on the surface. Dynamic studies assessed the effect of co-contaminants on iodide uptake in a column environment. Data was fitted to three dynamic models, with the Dose-Response model providing the best description of breakthrough. In all cases iodide breakthrough was accelerated, indicating suppression of uptake, but capacity was still significant

Molecular interaction studies of cinnamaldehyde with certain alcohols by ultrasonic method at 303.15 K

899-906The results of a new experimental study of thermo physical properties for eight binary systems of cinnamaldehyde with different alkanols have been presented. Speed of ultrasound (u), density () and viscosity () at 303.15 K and atmospheric pressure have been measured over the whole range of composition. These properties have been used to calculate various thermo acoustical parameters. The variations in these parameters have been studied in terms of nature and extent of interaction and the effect of structure of alcohols on the existing interactions. The non-ideal behaviour of the binary systems has been revealed through the sign and magnitude of excess velocity, viscosity deviation and other excess parameters. These parameters have been studied on the basis of dipole-dipole interactions and hydrogen bonding. The excess parameters have been fitted to polynomial type Redlich-Kister equation and the coefficients of the fitting have been found to support the present investigation. </span