Patent ID: 8829243
Filing Date: 2014-09-09
Classification: C08G

Abstract:
1. A method for removing methylene-bridged polyphenyl polyamines from an aqueous stream comprising said methylene-bridged polyphenyl polyamines, the method comprising the steps of providing a pertraction equipment comprising a membrane with a first side and a second side opposite to said first side; bringing an aqueous stream comprising methylene-bridged polyphenyl polyamines into contact with said first side of said membrane and bringing an organic stream into contact with said second side of said membrane, thereby causing the methylene-bridged polyphenyl polyamines to transfer from said aqueous stream through said membrane to said organic stream; wherein, before bringing the aqueous stream and organic stream in contact with said membrane, the membrane is wetted with a liquid having a surface tension of less than 40 mN/m; and wherein said liquid is toluene.