The present invention is directed to a two-component (2K) anhydrous composition comprising a first component (1) comprising calcium aluminate cement; Ground Granulated Blast Furnace Slag (GGBS); and fumed silica; and a second component (2) comprising calcined bauxite; and fused zirconia mullite.

Suggested is a solid formed with Si, Al, Ca, O and at least one of Na and K, characterized in that in the .sup.27Al-MAS-NMR spectra of the solid compared to the .sup.27Al-MAS-NMR spectrum of calcium aluminate, an additional signal is present which has a chemical shift which lies between that of the main peak of calcium aluminate and that peak of calcium aluminate which is closest to the main peak in the higher field. 2.

Suggested is a solid formed with Si, Al, Ca, O and at least one of Na and K, characterized in that in the .sup.27Al-MAS-NMR spectra of the solid compared to the .sup.27Al-MAS-NMR spectrum of calcium aluminate, an additional signal is present which has a chemical shift which lies between that of the main peak of calcium aluminate and that peak of calcium aluminate which is closest to the main peak in the higher field. 2.

The invention relates to a process for the preparation of a novel precipitated silica, wherein: a silicate is reacted with an acidifying agent, so as to obtain a silica suspension; said silica suspension is filtered, so as to obtain a filter cake; said filter cake is subjected to a liquefaction operation, optionally in the presence of an aluminium compound; wherein at least one polycarboxylic acid is added to the filter cake, during or after the liquefaction operation. It also relates to a novel precipitated silica and to its uses.

The invention relates to a process for the preparation of a novel precipitated silica, wherein: a silicate is reacted with an acidifying agent, so as to obtain a silica suspension; said silica suspension is filtered, so as to obtain a filter cake; said filter cake is subjected to a liquefaction operation, optionally in the presence of an aluminium compound; wherein at least one polycarboxylic acid is added to the filter cake, during or after the liquefaction operation. It also relates to a novel precipitated silica and to its uses.

Granular and/or shaped hydrophobic silica useful for thermal insulation materials are prepared by mixing hydrophilic silica with a hydrophobicizing agent at low temperature so the hydrophobicizing agent does not appreciably react, followed by deaeration and compaction.

Granular and/or shaped hydrophobic silica useful for thermal insulation materials are prepared by mixing hydrophilic silica with a hydrophobicizing agent at low temperature so the hydrophobicizing agent does not appreciably react, followed by deaeration and compaction.

The present disclosure is directed to a method of manufacturing gypsum board as well as the resulting gypsum board. The method comprises providing a gypsum slurry with a shrinkage-reducing additive comprising a metal salt of an acid, a silica, or a mixture thereof. As a result, the gypsum board includes gypsum and a shrinkage-reducing additive comprising a metal salt of an acid, a silica, or a mixture thereof. The gypsum board exhibits an area shrinkage of less than 10%.

The present disclosure is directed to a method of manufacturing gypsum board as well as the resulting gypsum board. The method comprises providing a gypsum slurry with a shrinkage-reducing additive comprising a metal salt of an acid, a silica, or a mixture thereof. As a result, the gypsum board includes gypsum and a shrinkage-reducing additive comprising a metal salt of an acid, a silica, or a mixture thereof. The gypsum board exhibits an area shrinkage of less than 10%.

A method for the preparation of industrial-scale concrete installations with improved compression strength, curling, cracking and cracking characteristics, the method comprising the addition of nanosilica particulate, and more preferably, colloidal amorphous silica, having specific size and surface area characteristics to a concrete mix after water has been added to the mix and the mix has been agitated.