Abstract: The present invention provides a method for treating water containing phenolic material such as bisphenol A, phenol, para tertiary butyl phenol, and 1,1,1-tris(hydroxyphenyl)ethane, as well as water soluble polycarbonate oligomers, and dispersed polycarbonate particles by extracting the phenolic material from the water using a water immiscible organic liquid containing an amine coupling catalyst. The treated water is then steam stripped to remove residual organic liquid and the amine. The organic liquid, containing the bisphenol A, phenol, para tertiary butyl phenol, and 1,1,1-tris(hydroxyphenyl)ethane, as well as water soluble polycarbonate oligomers and dissolved polycarbonate particles can be fed back to the coupling step of the polycarbonate process without further regeneration or treatment.

Abstract: The present invention provides a method for treating water containing phenolic material such as bisphenol A, phenol, para tertiary butyl phenol, and 1,1,1-tris(hydroxyphenyl)ethane, as well as water soluble polycarbonate oligomers, and dispersed polycarbonate particles by extracting the phenolic material from the water using a water immiscible organic liquid containing an amine coupling catalyst. The treated water is then steam stripped to remove residual organic liquid and the amine. The organic liquid, containing the bisphenol A, phenol, para tertiary butyl phenol, and 1,1,1-tris(hydroxyphenyl)ethane, as well as water soluble polycarbonate oligomers and dissolved polycarbonate particles can be fed back to the coupling step of the polycarbonate process without further regeneration or treatment.

Abstract: The diposphines have the formula (I) ##STR1## wherein: R.sup.2, R.sup.3 and R.sup.4 independently from each other represent a hydrocarbyl group which is substituted with one or more radicals selected from the group consisting of halogen, alkyl and alkoxy, andA is --C(O)--, --S(O).sub.2 --, --S(O)-- or certain divalent organic groups.The diphosphines are useful for stabilizing thermoplastic polymers, such as polycarbonates, against thermal discoloration.