Patent ID: 6884401

Claim:
A method for removing a volatile component from a high viscosity liquid by using a rotation pack bed, which comprises the following steps: a) introducing a high viscosity liquid into a rotation pack bed rotating around an axis, said rotation pack bed being located in a housing and comprising a central channel region around said axis and an annular pack region surrounding said central channel region, said annular pack region being packed with a packing, and said annular pack region and said central channel region being in fluid communication only through a boundary thereof, and said annular pack region and said housing being in fluid communication only through an outer circumference of said annular pack region, wherein said high viscosity liquid is introduced to a location in said annular pack region so that said high viscosity liquid receives a sufficient centrifugal force at said location and can radially flow through said packing from said location in a direction away from said axis; b) introducing a high pressure gas at a location near the outer circumference of said annular pack region, and/or connecting said central channel region to a suction source so that, when said highly viscous fluid radially flows through said packing, a volatile component in said high viscosity liquid together with aid high pressure gas or said volatile component per se flow out of said rotation pack bed and said housing in a gas phase from said central channel region; and c) collecting a purified liquid, which flows out from the outer circumference of said annular pack region, from a bottom of said housing, wherein said high viscosity liquid in step a) comprises tris nonylphenol phosphite, and hydrogen chloride contained in said tris nonylphenol phosphite, wherein said volatile component is said hydrogen chloride, and said purified liquid is a tris nonylphenol phosphite having a reduced amount of hydrogen chloride; or wherein said high viscosity liquid in step a) comprises polyurethane and an unreacted polyisocyanate monomer contained in said polyurethane, wherein said volatile component is said polyisocyanate monomer, and said purified liquid is a polyurethane having a reduced amount of polyisocyanate monomer.