The ion exchange material used in SIXEP to remove Sr and Cs from Sellafield effluent is the natural zeolite clinoptilolite. The focus of this project would be to investigate other families of porous silicates, for example some related to the CST in IONSIV, as new ion exchangers not only for Sr and Cs but other relevant cations that may require removal from effluent such as actinides or other metals.