Abstract: 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° 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.

Abstract: 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° 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.

Abstract: Solid mesoporous crystalline composition of a pyrophosphate-phosphate of a tetravalent metal, with a high surface area and narrow distribution of the mesopores, having formula (I):M(P.sub.2 O.sub.7).sub.1-z (HPO.sub.4).sub.2z (I)wherein: M is a tetravalent metal and z varies from 0.05 to 0.25.The process for its production is described together with its uses.

Abstract: Solid mesoporous crystalline composition of diphospho-nate-phosphite of a tetravalent metal, with a limited distribution of mesopores having the formulaM?(O.sub.3 P--R--PO.sub.3).sub.1-x-y (HPO.sub.3).sub.2x (O.sub.3 P--R--PO.sub.3 H.sub.2).sub.2y !wherein: M is a tetravalent metal, R is a bivalent organic radical, x varies from 0.3 to 0.6, y varies from 0.05 to 0.3. The process for its production is described, together with its uses and a solid catalyst containing --SO.sub.3 H acid groups, active in the conversion processes of hydrocarbons, which can be obtained from said mesoporous crystalline composition by treatment with a sulfonicphosphonic or arylphosphonic acid, followed, only in the case of treatment with arylphosphonic acid, by sulfonation with a sulfonating agent.

Abstract: A tetravalent metal diphosphonate-phosphite composition definable by the following general formula:M(O.sub.3 P--R--PO.sub.3).sub.1-x (HPO.sub.3).sub.2x (I)is described where:M is a tetravalent metal;x varies from 0.5 to 0.66;R is an organic radical of bivalent aromatic type, carrying side groups which increase its steric hindrance.The composition is in the form of a crystalline solid with a type .alpha. layered structure with the diphosphonic groups positioned to join said layers together by a covalent bond (pillared compounds). It has a B.E.T. surface area from 300 to 500 m.sup.2 /g depending on the nature of R in formula (I), and a porosity in the micropore radius range of less than 20 .ANG. (Angstrom), such micropores contributing to the extent of more than 95% of the total area for the most crystalline materials.

Abstract: The present invention discloses a compound comprising a diphosphonate/phosphite of a tetravalent metal:M[(O.sub.3 P--R--PO.sub.3).sub.1-(x+y) (HPO.sub.3).sub.2X (O.sub.3 P--R--PO.sub.3 H.sub.2).sub.2y ](where M, R, x and y have the meaning given in the description), in the form of a crystalline solid with an alpha-type lamellar structure with a distance between layers of 7.4 to 20.ANG. (depending on the dimensions of radical R), a BET surface area of 250 to 400m.sup.2 /g, and porosity within the mesopore range, with at least 50% of the pores measuring 20 to 30.ANG.. The compound, depending on the radical R used, may or may not have microporosity in the region between layers. Such a diphosphonate/phosphite of a tetravalent metal is obtained by reaction between diphosphonic acid, phosphorous acid and an oxyhalide of a tetravalent metal, in a solvent comprising dimethyl-sulphoxide/water containing hydrofluoric acid.