Distillation of tall oil

Claim 1

A TWO-STAGE PROCESS FOR OBTAINING SUBSTANTIALLY PURE FATTY ACIDS AND RESIN ACIDS FROM TALL OIL CONTAINING THE SAME AS WELL AS COMPARATIVELY NON-VOLATILE AND UNSAPONIFIABLE COMPONENTS WHICH COMPRISES IN THE FIRST STAGE SUBJECTING THE TALL OIL TO DISTILLATION IN COMPARATIVELY THIN LAYERS UNDER SUBSTANTIALLY HIGH VACUUM WITH THE AID OF WET STEAM, THE DISTILLATION TEMPERATURE BEING MAINTAINED ABOVE THE BOILING POINT OF THE FATTY ACIDS THEREIN AND BELOW THAT OF THE RESIN ACIDS CONTENT, SAID TEMPERATURE BEING WITHIN THE APPROXIMATE RANGE OF 230* TO 240* C., CONDUCTING THE VAPORS EVOLVED BY THE SAID DISTALLATION TO A RECTIFICATION ZONE FOR FRACTIONALLY SEPARATING VAPOR CONSTITUENTS, MAINTAINING A DEPHLEGMATION ZONE, AT A TEMPERATURE OF APPROXIMATELY 200* C., AT THE OUTLET END OF THE RECTIFICATION ZONE, WHEREBY COMPONENTS CONDENSED IN THE SAID RECTIFICATION ZONE RETURN TO THE DISTILLATION ZONE CONTAINING TALL OIL RESIDUE, CONDUCING THE VAPORS EVOLVED FROM THE RECTIFICATION ZONE TO A FIRST ONE OF CONDENSATION MAINTAINED AT A TEMPERATURE APPROXIMATELY WITHIN THE RANGE OF 150* C. TO 180* C., THEREBY CONDENSING FATTY ACIDS OF APPROXIMATELY 18C ATOMS, CONDUCTING THE VAPORS EVOLVED FROM SAID FIRST CONDENSATION ZONE TO A SECOND CONDENSATION ZONE MAINTAINED AT A TEMPERATURE BELOW THAT OF THE FIRST CONDENSATION ZONE FOR SEPARATING ADDITIONAL FATTY ACIDS HAVING A LOWER NUMBER OF C ATOMS, SUBJECTING THE REMAINING VOLATILE COMPONENTS FROM THE SAID SECOND CONDENSATION ZONE TO FUTHERR CONDENSATION, SAID FINAL CONDENSATION BEING ADAPTED TO PRODUCE A VACUUM BELOW APPROXIMATELY 5 MM. HG, THE VACUUM DURING ALL OF THE AFORESAID TREATMENT, INCLUDING THAT IN THE DISTILLATION, RECTIFICATION AND CONDENSATION ZONES, BEING MAINTAINED BELOW APPROXIMATELY 20 MM. HG; AND IN THE SEEOND STAGE, CONDUCTING THE TALL OIL RESIDUE, COMPRISING RESIN ACIDS AND THE COMPARATIVELY NON-VOLATILE UNSAPONIFIABLE COMPONENTS OF THE TALL OIL, FROM THE FIRST STAGE DISTILLATION TREATMENT TO A SECOND DISTILLATION ZONE, SUBJECTING THE SAID RESIDUE IN THE LATTER ZONE TO DISTILLATION WITH THE AID OF WET STEAM IN COMPARATIVELY THIN LAYERS UNDER SUBSTANTIALLY HIGH VACUUM, THE TEMPERATURE IN THE DISTILLATION ZONE BEING MAINTAINED APPROXIMATELY WITHIN THE TEMPERATURE RANGE OF 290* C. TO 310* C., CONDUCTING THE VAPORS EVOLVED BY THE SAID DISTILLATION TO A RECTIFICATION ZONE FOR FRACTIONALLY SEPARATING VAPOR CONSTITUENTS, MAINTAINING A DEPHLEGMATION ZONE AT A TEMPERATURE APPROXIMATELY WITH THE RANGE OF 190* C. TO 200* C., AT THE OUTLET END OF THE LATTER RECTIFICATION ZONE, WHEREBY THE RELATIVELY VOLATILE COMPONENTS, INCLUDING ANY FATTY ACID CONSTITUENTS, ARE SEPARATED FROM THE RESIN ACIDS CONDENSED IN SAID RECTIFICATION ZONE, CONDUCTING THE SAID VOLATILE COMPONENTS TO A CONDENSATION ZONE FOR RECOVERING FATTY ACIDS, AND CONDUCTING THE RESIN ACIDS FROM A POINT APPROXIMATELY ADJACENT THE INLET END OF THE RECTIFICATION ZONE TO COLLECT THE SAME, THE VACUUM CONDITIONS DURING THE AFORESAID SECOND STAGE OF TREATMENT BEING MAINTAINED BELOW APPROXIMATELY 20 MM. HG.