This invention is based on the preparation of new solid acid triphosphates with compositions of the general formula M(IV)(HPO4)(H2PO4)2, where M(IV) is a tetravalent metal or a mixture of tetravalent metals. These compounds are insoluble in water the greater part of most organic solvents. They show a high non-water assisted protonic conductivity (about 0.01-0.04 S/cm at 100.degree. C. and a relative humidity lower than 1%). These compounds can be used as proton conduction separators in electrochemical devices, to operate at low relative humidity values, as for example in different fuel cells, protonic pumps for electrochemical hydrogenation and dehydrogenation of organic compounds, or for hydrogen production from hydrogenated organic compounds by electro-reforming, or also for removing hydrogen from equilibrium reactions. These compounds can also be used in electrochemical sensors, in super capacitors and as acid catalysts in non-aqueous or anhydrous gaseous phases.