Hydrophobised calcium carbonate particles

摘要

The present invention relates to a process for the reduction of pitch in an aqueous medium generated in a papermaking or pulping process, comprising the following steps: a) providing an aqueous medium comprising pitch generated in a papermaking or pulping process; b) providing a ground calcium carbonate and/or a precipitated calcium carbonate; c) providing a hydrophobising agent selected from an aliphatic carboxylic acid having between 5 and 24 carbon atoms; d) contacting the ground calcium carbonate and/or the precipitated calcium carbonate of step b) with the hydrophobising agent of step c) for obtaining a hydrophobised ground calcium carbonate and/or a hydrophobised precipitated calcium carbonate; and e) contacting the aqueous medium provided in step a) with the hydrophobised ground calcium carbonate and/or the hydrophobised precipitated calcium carbonate obtained in step d), to the use of a hydrophobised ground calcium carbonate and/or a hydrophobised ground calcium carbonate for reducing the amount of pitch in an aqueous medium as well as to a hydrophobised ground calcium carbonate and/or a hydrophobised ground calcium carbonate and a composite of hydrophobised ground calcium carbonate and/or hydrophobised ground calcium carbonate and pitch.