Process for the production of free-flowing, stable foam inhibitor concentrates by compacting granulation

摘要

Free-flowing, particulate foam inhibitor concentrates, which suffer no loss of activity in admixture with surfactants or strong alkalis, are prepared by compacting a mixture of from 1 to 20% by weight of the foam inhibitor with 80 to 99% by weight of a water-soluble salt or salt mixture optionally containing blending aids and having a pH value in the form of a 1% aqueous solution of from 6 to 9.5 under elevated pressure and subsequently size-reducing the compactate to an average particle size of from 0.1 to 2 mm. The presssure applied to the mixture should not significantly exceed the pressure limit at which no further compaction occurs. In addition, the particle porosity, as measured by mercury porosimetry, should be below 10%. The foam inhibitors used are preferably paraffin hydrocarbons, organopolysiloxanes and mixtures thereof with finely-divided hydrophobic solids, particularly finely-divided silica.