Diethanolamine reclamation

Claim 1

IN A PROCESS WHERIN PETROLEUM FRACTIONS CONTAINING RELATIVELY LARGE AMOUNTS OF HYDROGEN SULFIDE AND RELATIVELY SMALL AMOUNTS OF STRONGER ACIDS ESSENTIALLY FROM THE GROUP CONSISTING OF FORMIC, ACETIC AND THIOCYANIC ACIDS ARE CONTACTED WITH AQUEOUS DIETHANOLAMINE SOLUTION TO REMOVE, BY CHEMICAL REACTION, SAID HYDROGEN SULFIDE AND SAID STRONGER ACIDS, SAID DIETHANOLAMINE SOLUTION BEING REGENERATED BY STEAM-STRIPPING SAID HYDROGEN SULFIDE-THEREFROM BUT SAID STRONGER ACIDS NOT BEING REMOVABLE BY SAID STRIPPING, THE EXHAUSTION OF THE DIETHANOLAIME BY THE GRADUAL FORMATION OF SALTS WITH SAID STRONGER ACID BEING RETARDED BY ADDING SODIUM HYDROXIDE WITH THE RESULTANT ACCUMULATION OF SODIUM SALTS OF SAID STRONGER ACIDS IN A CONTAMINATED SOLUTION; THE METHOD OF OBTAINING REUSUABLE DIETHANOLAMINE SOLUTION FREE FROM SAID SODIUM SALTS, COMPRISING ADDINGS POTASSIUM HYDROXIDE IN QUANTITIES BETWEEN ONE-HALF AND ONE-TWENTIETH OF THE AMOUNT OF SAID SODIUM HYDROXIDE PREVIOUSLY ADDED, THE TOTAL HYDROXIDE BEING IN SUBSTANTIAL EXCESS OVER THAT REQUIRED TO FREE THE DIETHANOLAMINE FROM ITS SAID SALTS BY RELACING ITS IRON WITH THOSE OF SODIUM AND POTASSIUM; INJECTING A STREAM OF THE RESULTANT SAOLUTION CONTAINING UNCOMBINED DIETHANOLAMINE AND SOLIUJM AND POTASSIUM SALTS OF SAID STRONGER ACIDS INTO THE UPPER PORTION OF A RECLAIMINMG ZONE TO PASS DOWNWARDLY THROUGFH SAID ZONE; MAINTAINING A HOT POOL CONSISTING PRINCIPALLY OF SAID SODIUM AND POTASSIUM SALTS OF SAID STRONGER ACIDS IN A MOLTEN STATE BETWEEN 440* F. AND 465* F. BELOW SAID ZONE, TOWARD WHICH SAID STREAM PASSES AND AT THE SURFACE OF WHICH SAID DIETHANOLAMINE AND WATER ARE IMMEDIATELY VAPORIZIED; INJECTING STREAM INTO SAID POOL AND PASSING SAID STREAM UPWARDLY THERETHROUGH AND THROUGH SAID ZONE COUNTER-CURRENTLY TO SAID STREAM, WITHDRAWING A MIXTURE OF DIETHANOLAMINE VAPOR AND WATER ABOVE THE LEVEL OF SAID POOL; CONDENSING THE WITHDRAW VAPORS TO AN AQUEOUS SOLUTION OF SUBSTANTIALLY PURE DIETHANOLAIME; AND RETURNING THE WITHDRAWN DIETHANOLAMINE TO SAID PROCESS FOR TREATING PETROLEUM FRACTIONS.