Heterogeneous catalytic Fenton of Rhodamine B (RhB) was enhanced by magnetic waste iron slag composite (MIS) as a novel catalyst. The MIS was successfully enriched by an increase in mass rate of Fe element from 26.60% (in iron slag-IS) to 50.68% (in MIS-10). Besides, the textural properties of MIS-10 were remarkably improved in porous structure and BET specific surface area compared with IS. An almost complete degradation of RhB was obtained at the composite ratio between mixture of (Fe${}^{2+}$ and Fe${}^{3+}$) and IS of 10% (w/w), solution pH of 3, H₂O₂ of 1680 mg/L and catalyst dosage of 4000 mg/L for both IS/H₂O₂ and MIS-10/H₂O₂ systems within 120 min reaction time At this optimal operational condition, the decolorization and mineralization of RhB, respectively, reached 71.84% and 59.75% for IS/H₂O₂ system and 98.48% and 83.33% for MIS-10/H₂O₂ system. The first-order reaction rate constant (K${}_{\mathrm{d}}$) values of the pseudo-first-order kinetic followed the same sequence as COD removal. The Fe amount enriched in MIS-10’s constituent was proved the improving considerably reaction rate with H₂O₂ to generate continuously more hydroxyl (${}^{.}$OH) radicals which led to higher oxidation of RhB by MIS-10/H₂O₂ compared with IS/H₂O₂. The mechanisms of RhB enhanced degradation included adsorption, leaching iron through homogeneous Fenton reactions and heterogeneous Fenton reaction. The main mechanism of RhB oxidation by MIS-10/H₂O₂ system was through ${}^{.}$OH which was produced by heterogeneous Fenton reaction due to the contribution of Fe elements enriched on the catalyst’s surface. The MIS-10 exhibited a high stability with very low iron leaching and maintained a high catalytic activity after 5 successive cycles, indicating MIS-10 is fully promising catalyst for Fenton oxidation of persistent organic compound from wastewater.

罗丹明B（RhB）的非均相催化Fenton被新型的磁性废铁渣复合物（MIS）增强。通过将Fe元素的质量比率从26.60％（铁渣IS中）提高到50.68％（MIS-10中），成功地使MIS富集。此外，与IS相比，MIS-10在多孔结构和BET比表面积方面的结构性能得到了显着改善。在（Fe${}^{\mathrm{2个}+}$ 和铁${}^{3+}$），IS / H ₂ O ₂和MIS-10 / H ₂ O的IS为10％（w / w），溶液pH为3，H ₂ O ₂为1680 mg / L，催化剂剂量为4000 mg / L在120分钟的反应时间内有_2个系统在此最佳操作条件下，对于IS / H ₂ O ₂系统，RhB的脱色和矿化分别达到71.84％和59.75％，对于MIS-10 / H ₂ O分别达到98.48％和83.33％₂系统。一阶反应速率常数（K${}_{\mathrm{d}}$）假一阶动力学值遵循与去除COD相同的顺序。事实证明，富含MIS-10成分的Fe量显着提高了与H ₂ O _2的反应速率，从而连续产生更多的羟基（${}^{。}$与IS / H ₂ O ₂相比，MIS-10 / H ₂ O ₂导致RhB氧化程度更高。RhB增强降解的机理包括吸附，通过均相Fenton反应浸出铁和非均相Fenton反应。MIS-10 / H ₂ O ₂体系氧化RhB的主要机理是通过${}^{。}$由于催化剂表面富集的Fe元素的作用，通过非均相Fenton反应生成的OH。MIS-10表现出很高的稳定性，铁的溶出量非常低，并且在连续5个循环后仍保持较高的催化活性，这表明MIS-10是Fenton氧化废水中持久性有机化合物的完全有前途的催化剂。