Continuous process for leaching an iron-aluminum alloy

Claim 1

A CONTINUOUS PROCESS FOR THE LEACHING OF AN IRON-ALUMINUM ALLOY, WHICH COMPRISES INTRODUCING FINELY COMMINUTED PARTICLES OF SAID ALLOY INTO AN AQUEOUS CAUSTIC ALKALI SOLUTION, MAINTAINING THE SOLUTION IN THE UPPER PART OF SAID COLUMN AT NEAR ITS BOILING TEMPERATURE DURING INTRODUCTION OF SAID ALLOY, INTRODUCING A COLD FRESH AQUEOUS CAUSTIC ALKALI SOLUTION NEAR THE BOTTOM OF SAID COLUMN, WITHDRAWING SPENT CAUSTIC ALKALI SOLUTION NEAR THE TOP OF SAID COLUMN, CONTROLLING THE INFLOW OF FRESH CAUSTIC ALKALI SOLUTION AT SUCH A RATE AS TO MAINTAIN THE LOWER PART OF SAID COLUMN RELATIVELY COOL WITH RESPECT TO THE UPPER PART OF SAID COLUMN BUT NOT AT A SUFFICIENTLY RAPID RATE TO CAUSE PARTICLES PRESENT IN SAID UPPER PART TO PASS OUT WITH THE SPENT CAUSTIC ALKALI SOLUTION AND INTERMITTENTLY RELEASING THE LEACHED PARTICLES FROM THE BOTTOM OF THE CAUSTIC ALKALI SOLUTION COLUMN INTO THE TOP OF AN UPWARDLY FLOWING COLUMN TO WASH WATER.