公开(公告)号：BRPI0413915A

公开(公告)日：2006-10-24

申请号：BRPI0413915

申请日：2004-08-27

Applicant: BASF AG

Inventor： DYLLICK-BRENZINGER RAINER ,  SCHMID MARKUS ,  WEHRLE J RG ,  LORENZ KLAUS ,  BRUHNS STEFAN ,  SENGE MICHAEL

IPC: B01D19/04 ,  B01J13/04

Abstract: Emulsifier-free antifoams are obtainable by mixing a) from 80 to 99% by weight of at least one finely divided, virtually water-insoluble, inert solid with b) from 1 to 20% by weight of at least one hydrophobic, organic compound which has an antifoam action and is solid at room temperature in the absence of a solvent in a shear gradient such that the particle size of the compounds (b) which have an antifoam action is reduced to a mean particle size of from 0.5 to 15 mum, emulsifier-free oil-in-water dispersions of mixtures of (a) and (b) are prepared by mixing the component (a) in an amount of from 80 to 99% by weight with the compounds of component (b) in an amount of from 1 to 20% by weight in the absence of emulsifiers in an extruder or kneader in a manner such that the mean particle size of the component (b) in the mixture is brought to 0.5 to 15 mum, at up to 100° C., and emulsifying the mixture in water, and the oil-in-water dispersions thus obtainable are used as antifoams and/or deaerators for aqueous, disperse or nondisperse liquids, in particular as antifoams and/or deaerators in the paper industry, in the food industry and in wastewater treatment plants.