Method for repairing hexavalent chromium in chromium polluted soil

The invention discloses a method for repairing hexavalent chromium in chromium polluted soil by adopting alkaline solution of ethylenediamine tetracetic acid salt through leaching, and belongs to the technical field of treatment of heavy metal polluted soil. The method for repairing the hexavalent chromium in the chromium polluted soil adopts 0.02-0.15 mol/L water solution of ethylenediamine tetracetic acid sodium, and adds alkali or water solution thereof for mixing to prepare alkalescent mixed solution with a pH value of 8.0-10.0; the solution serves as a leaching agent of the hexavalent chromium in the chromium polluted soil; the leaching agent is used for mixing and leaching the chromium polluted soil; the liquid-solid ratio of the leaching agent to the chromium polluted soil is 1 L: 50-450 g; the leaching temperature is 0-40 DEG C; the leaching time is 30-240 min; the solid-liquid separation is performed; the separated solid is soil, and is dried in air for direct landfill or other purposes; and the separated liquid is solution containing the hexavalent chromium. The method has the advantages of simple preparation of the leaching agent, low energy consumption and short technological flow; the removal rate of the hexavalent chromium can reach above 99%; and the influence of the hexavalent chromium on soil, underground water and surrounding environment is effectively restrained.