Background: 4-Chlorophenol is used frequently in industries including refineries petrochemical, industries pesticide industries and many others. This compound causes damage to environment. The purpose of this research was the survey of 4-chlorophenole degradation by Fe°/H₂O₂ of synthetic wastewater and resulting intermediate compounds.

  Methods: This study is an applied- experimental research which was performed in laboratory scale. The parameters such as pH, hydrogen peroxide, contact time, iron powder and mixing velocity were investigated in the removal of 4-chlorophenole. UV₂₁₅ and COD indexes were studied related to produced intermediate compounds .

  Results: The best conditions for the removal of 4-chlorophenol were achieved in pH 4, the ratio of hydrogen peroxide to 4-chlorophenol 18.8, the ratio of hydrogen peroxide to iron powder 0.4, contact time of 5min and mixing velocity of 180rpm. For investigating mineralization of 4-chlorophenol, COD index was used It was observed that 4-chlorophenol was not mineralized absolutely. Decrease of chlorinated properties and aromatic compounds in solution, as well as improve ment of 4- chlorophenol decomposition were achieved with increasing chloral ion and UV₂₁₅ index in 5minute.

  Conclusion : Regarding the results and considering the high resistance of 4-chlorophenole in biological treatment, can be used Fe^°/H₂O_{2 for producing compounds with high decomposition and low toxicity}

  Advanced oxidation process, Fenton-like, 4- chlorophenole, COD, Chemical degradation