Control of the Isotopic Exchange for18O Isotope Production

In this paper, a method to control the concentration of the 180 isotope, produced through isotopic exchange in the system NO, NO2-H2O, HNO3, is presented. The isotopic exchange process is modeled as a distributed parameter process, its structure parameters being determined using experimental data. The applied control strategy is based on using an adaptive PI controller. The adaptive PI controller is integrated in a complex control structure designed to improve the control performances. The control performances are, also, improved using the physical properties of the isotopic exchange process.