Resin-asphaltene concentrates were obtained by the redox reaction of acid tar and naphtha deasphalting residue and used for fabrication of sulfo-cation exchangers. The strongly acid powdered sulfo cation exchanger with a static exchange capacity of 3.8 meq/g and mechanical strength of 92% is characterized by elevated thermohydrolytic stability and radiation stability. Based on its properties, it can be used in metal-gauze-asbestos gravity filters at atomic power plants for preliminary treatment of water.