Abstract: A process which comprises reacting phenol and acetone in the presence of an acidic catalyst and thereaftera. isolating first major portion of bisphenol-A, therefore forming a purge stream comprising bisphenol-A, bisphenol-A isomers and tar,b. adding or taking from the said purge stream, if necessary, sufficient phenol so as to bring the purge stream ratio of phenol to bisphenol-A to about 5:1 to 15:1 based on moles, thereby forming an altered purge stream,c. bringing the temperature of the altered stream to a range of about 30.degree.-50.degree. C.,d. maintaining the temperature of the altered stream at about 30.degree.-50.degree. C. until about 60-85% of the bisphenol-A crystallizes as a bisphenol-A/phenol 1:1 molar adduct,e. separating the adduct from its mother liquor.