摘要:), which is promising as a form of the final storage. In this processing, the clays are used as a source for aluminum and silicon, and it is important to get a well-mixed homogenous solution by the aid of some heat and pressure. The present method proposes the use of ethylene glycol as a solvent, rather than water. It has been found that one can obtain crystalline pollucite by heating up to 350 °C in a high-pressure container (~15 MPa), mixed with montmorillonite - an abundant natural clay and ethylene glycol. It has been found that the reduction of the amount of water helps to achieve very high confinement rate in a reasonable time of few~20 h. This will be fairly important in processing contaminated water in the nuclear power plant. The influence of seawater has been also examined.