help about equilibrate phenol

[Bethune international peace hospital]

Hi
 How to equilibrate phenol to a PH>7.8?
    We have equilibrate phenol for one week with Tris.Cl(1M,PH8.0),
but the PH of penol phase is still under 7.0  and much phenol lose.
            thank you for help 
responds to:
       genet at public.sj.he.cn