PROCESS FOR THE EXTRACTION OF SILICA

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.