Process and apparatus for concentrating hydrogen peroxide

Claim 1

A PROCESS FOR THE CONCENTRATION OF HYDROGEN PEROXIDE WHICH COMPRISES PASSING THE HYDROGEN PEROXIDE SOLUTION TO BE CONCENTRATED IN CO-CURRENT FLOW WITH HOT VAPOUR UP A TUBE WHOSE LENGTH IS AT LEAST TEN TIMES ITS WIDTH, CAUSING SAID HOT VAPOUR TO FLOW AT A SUFFICIENT VELOCITY TO CARRY SAID SOLUTION THEREWITH MIXED WITH THE VAPOUR AND FOR A DISTANCE SUFFICIENT TO ESTABLISH SUBSTANTIAL THERMODYNAMIC EQUILIBRIUM BETWEEN THE LIQUID AND VAPOR PHASES OF SAID MIXTURE PASSING THE MIXTURE OF VAPOUR AND LIQUID LEAVING THE TUBE TO A SEPARATOR WHERE IT IS SEPARATED INTO A VAPOUR CONTAINING HYDROGEN PEROXIDE AND A CONCENTRATED LIQUID CONTAINING HYDROGEN PEROXIDE, RETURNING A PART OF THE CONCENTRATED LIQUID TO THE LOWER PART OF SAID TUBE AND REMOVING THE REMAINDER FROM CIRCULATION, PASSING THE VAPOUR CONTAINING HYDROGEN PEROXIDE TO THE LOWER PART OF A SECOND TUBE WHOSE LENGTH IS AT LEAST TEN TIMES ITS WIDTH THROUGH WHICH IT IS PASSED UPWARDLY IN CO-CURRENT FLOW WITH A LIQUID SELECTED FROM THE GROUP CONSISTING OF WATER AND HYDROGEN PEROXIDE SOLUTIONS WHICH ARE MORE DILUTE THAN THE HYDROGEN PEROXIDE INTRODUCED INTO SAID FIRST TUBE, CAUSING SAID VAPOUR TO FLOW AT A SUFFICIENT VELOCITY TO CARRY SAID LIQUID THEREWITH MIXED WITH THE VAPOUR AND FOR A DISTANCE SUFFICIENT TO ESTABLISH SUBSTANTIAL THERMODYNAMIC EQUILIBRIUM BETWEEN THE LIQUID AND VAPOR PHASES OF SAID MIXTURE, PASSING THE MIXTURE OF VAPOUR AND LIQUID LEAVING THE SECOND TUBE INTO A SECOND SEPARATOR WHERE IT IS SEPARATED INTO A RELATIVELY CONCENTRATED LIQUID CONTAINING HYDROGEN PEROXIDE AND VAPOUR, RETURNING A PART OF THE RELATIVELY CONCENTRATED LIQUID TO THE LOWER END OF SAID SECOND TUBE AND FEEDING ANOTHER PART TO THE LOWER END OF SAID FIRST TUBE.