The application of nano silica extracted from kaolinite, bentonite and rice straw is proposed as treatment material for the purification of primary coolant water of pressurized water reactors. Three elements were used to simulate some radionuclides that can be released in the primary coolant water namely, strontium, nickel and cobalt. Various batch experiments were performed including selection of efficient sorption nanomaterial, optimum operational weight ratio (element/nano material), selectivity of the nano silica for elements used, determination of the equilibrium curve of sorption process, and desorption behavior of nanomaterial with pH and temperature variation. The samples were analyzed using the inductively coupled plasma emission spectrometer. Silica of kaolinite, bentonite and rice straw showed the same results in the efficiency/ capability removing the three elements used. Silica form of rice straw has been selected as nano-treated materials for economic and environmental reasons. The sorption process reached equilibrium after 30 min approximately. The experiments demonstrated that the sorption reaction of elements by the nano-silica is an irreversible reaction with the change of temperature and pH. The obtained results indicated that using the nano silica increased the safety margin of the treatment stage in the multi barrier concept.

No abstract