Fe-based monolithic catalysts for Fenton-like degradation of organic dyes: The important role of Fe2(OH)3Cl species

Fe-based heterogeneous catalysts are promising in Fenton-like reactions for wastewater treatment, but their practical application is hindered by their recyclability, and the fundamental mechanisms for origin of the high performance and the structure-activity relationships remain to be elucidated further. In this paper, we prepared a series of Fe₂(OH)₃Cl-containing monolith catalysts by the use of NH₄Cl additives, which gave significantly higher performance than the Fe₃O₄ counterparts in Fenton-like degradation of methylene blue and rhodamine B when H₂O₂ was used as oxidant. The Fe₂(OH)₃Cl-containing monolith catalyst can be reused four cycles in the degradation experiments without big loss in their activity. The active radicals generated during process of the catalytic degradation were studied.