This disclosure relates to new crystalline microporous solids (including silicate- and aluminosilicate-based solids), the compositions comprising 8 and 10 membered inorganic rings, particularly those having RTH topologies having a range of Si:Al ratios, methods of preparing these and known crystalline microporous solids using certain quaternized imidazolium cation structuring agents.

This disclosure relates to new crystalline microporous solids (including silicate- and aluminosilicate-based solids), the compositions comprising 8 and 10 membered inorganic rings, particularly those having CIT-7 topologies having a range of Si:Al ratios, methods of preparing these and known crystalline microporous solids using certain quaternized imidazolium cation structuring agents.

This disclosure relates to new crystalline microporous solids (including silicate- and aluminosilicate-based solids), the compositions comprising 8 and 10 membered inorganic rings, particularly those having HEU topologies having a range of Si:Al ratios, methods of preparing these and known crystalline microporous solids using certain quaternized imidazolium cation structuring agents.

The invention relates to: a -type iron silicate which has a fluorine content not more than 400 ppm by weight on a dry basis and in which the crystal grains have a truncated square bipyramidal morphology in an examination with a scanning electron microscope and the whole or part of the iron is contained in the -type framework structure, and a process for producing the iron silicate; anther -type iron silicate, and a process for producing the iron silicate; and a nitrogen oxide removal catalyst containing the other -type iron silicate, a process for producing the catalyst, and a method for nitrogen oxide removal with the catalyst.

Iron-based crystal structures including FeO.sub.4 tetrahedrally coordinated in three dimensions in a framework analogous to a zeolite. The structures having the general formula A.sub.yB.sub.8Fe.sub.12O.sub.24(O/OH).sub.6.xH.sub.2O in which A is Na, K, Cs, Rb or a combination thereof and B is an alkaline earth element or a combination of alkaline earth elements.

The present invention relates to a composition including a -type iron silicate, which includes all or part of iron in a -type framework structure, and a solid acidic porous inorganic oxide. The present invention is characterized in that the -type iron silicate is compounded with the porous inorganic oxide having solid acidic properties so that the solid acidic function derived from aluminum of the -type iron silicate, is reinforced or complemented by the porous inorganic oxide, the individual particles of which are physically isolated from each other. It is preferred that the fluorine content relative to the dry weight of the -type iron silicate is 400 ppm or less and the crystal particles of the -type iron silicate have a truncated square bipyramidal morphology. According to the present invention, a composition that is useful as a high-performance catalyst, adsorbent, or the like, can be provided.