The present invention provides a mesoporous silica comprising of components A and B such that component A is a surfactant of a saponin family and component B is a precursor of a silica. The present inventions also provides a method of producing said mesoporous silica by mixing components A and B in a solvent.

The present invention provides a mesoporous silica comprising of components A and B such that component A is a surfactant of a saponin family and component B is a precursor of a silica. The present inventions also provides a method of producing said mesoporous silica by mixing components A and B in a solvent.

A chemically modified precipitated silica characterised by the presence of methyl moieties chemically bound to the silica and a process for its manufacture.

A chemically modified precipitated silica characterised by the presence of methyl moieties chemically bound to the silica and a process for its manufacture.

Provided is a hydrophilic precipitated silica which is well suited to use in silicone rubber formulations (RTV-1, RTV-2, HTV and LSR), particularly well suited to use in HTV silicone rubber formulations. It has a BET surface area of 185˜260 m.sup.2/g, a CTAB surface area of 100˜160 m.sup.2/g, a BET/CTAB ratio of 1.2˜2.6, and a conductivity of <250 μS/cm. Also provided are a process for producing the precipitated silica and the use of the precipitated silica for thickening and reinforcing silicone rubber formulations.

Provided is a hydrophilic precipitated silica which is well suited to use in silicone rubber formulations (RTV-1, RTV-2, HTV and LSR), particularly well suited to use in HTV silicone rubber formulations. It has a BET surface area of 185˜260 m.sup.2/g, a CTAB surface area of 100˜160 m.sup.2/g, a BET/CTAB ratio of 1.2˜2.6, and a conductivity of <250 μS/cm. Also provided are a process for producing the precipitated silica and the use of the precipitated silica for thickening and reinforcing silicone rubber formulations.

A process for preparing precipitated silica comprising a precipitation reaction between silicate and an acid, in which the acid used in at least one of the steps is a concentrated acid, preferably selected from the group consisting of sulfuric acid having a concentration of at least 80% by weight, in particular at least 90% by weight, acetic acid having a concentration of at least 90% by weight, formic acid having a concentration of at least 90% by weight, nitric acid having a concentration of at least 60% by weight, phosphoric acid having a concentration of at least 75% by weight, and hydrochloric acid having a concentration of at least 30% by weight.

A process for preparing precipitated silica comprising a precipitation reaction between silicate and an acid, in which the acid used in at least one of the steps is a concentrated acid, preferably selected from the group consisting of sulfuric acid having a concentration of at least 80% by weight, in particular at least 90% by weight, acetic acid having a concentration of at least 90% by weight, formic acid having a concentration of at least 90% by weight, nitric acid having a concentration of at least 60% by weight, phosphoric acid having a concentration of at least 75% by weight, and hydrochloric acid having a concentration of at least 30% by weight.

Disclosed is a process for the extraction of silica from lignocellulosic plant matter, including the steps of: a) fractionating the lignocellulosic plant matter in the presence of an acid solution, so as to obtain a solid fraction including cellulose; b) extracting the silica from the solid fraction obtained in step a) with a basic solution, at a pH between 10 and 13 and at a temperature between 70° C. and 90° C., so as to obtain a liquid phase including silica and a solid phase; c) separating the liquid phase and of the solid phase which are obtained in step b); and d) precipitating the silica which is included in the liquid phase, at a pH between 5 and 6.

Disclosed is a process for the extraction of silica from lignocellulosic plant matter, including the steps of: a) fractionating the lignocellulosic plant matter in the presence of an acid solution, so as to obtain a solid fraction including cellulose; b) extracting the silica from the solid fraction obtained in step a) with a basic solution, at a pH between 10 and 13 and at a temperature between 70° C. and 90° C., so as to obtain a liquid phase including silica and a solid phase; c) separating the liquid phase and of the solid phase which are obtained in step b); and d) precipitating the silica which is included in the liquid phase, at a pH between 5 and 6.