Al-Fe loaded sepiolite catalysts with different active metal ratio have been synthesized using a Turkish sepiolite sample from Eskişehir region. Liquid phase catalytic oxidation of methyl orange azo dye has been carried out over Al-Fe/sepiolite catalysts using hydrogen peroxide as oxidant. The catalytic studies are performed in a glass reactor under atmospheric pressure by semi-batch operation. The effects of several parameters such as catalyst amount, metal loading, calcination temperature, pH, H₂O₂ concentration, reaction temperature and time on the methyl orange elimination have been examined. The elimination rate of 90.68% was achieved when studied with the catalyst with 8% active metal ratio (SepAlFe8) at pH 3.7 and 25°C. Kinetics studies show the degradation of methyl orange over the SepAlFe8 catalyst could be expressed by the pseudo-first-order reaction kinetics (k₁ = 0.0049 min^-1 at 25°C). The activation energy (E_a) of the reaction over this catalyst is foundas 29.48 kJ mol^-1. It was also found that the catalytic oxidation process is endothermic (ΔH = 26.99 kJ mol^-1) and nonspontaneous (ΔG = 96.72 kJ mol^-1 at 25°C). The catalyst is chemically stable and reusable with low release of iron.

中文翻译：

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用于甲基橙CWPO的新型且高度稳定的负载Al-Fe的海泡石催化剂的制备：理化参数，动力学和热力学研究的优化

使用来自埃斯基谢希尔地区的土耳其海泡石样品合成了具有不同活性金属比的载有Al-Fe的海泡石催化剂。甲基橙偶氮染料的液相催化氧化已使用过氧化氢作为氧化剂在Al-Fe /海泡石催化剂上进行。催化研究是在玻璃反应器中在大气压下通过半间歇操作进行的。考察了催化剂用量，金属负载量，煅烧温度，PH，H ₂ O ₂浓度，反应温度和时间等几个参数对甲基橙消除的影响。当使用活性金属比为8％（SepAlFe8）的催化剂在p下进行研究时，去除率为90.68％。高温3.7和25°C。动力学研究表明，甲基橙在SepAlFe8催化剂上的降解可以通过拟一级反应动力学来表示（在25°C下k ₁ = 0.0049 min ^-1）。发现该催化剂上反应的活化能（E _a）为29.48 kJ mol ^-1。还发现，催化氧化过程是吸热的（ΔH＝26.99kJ mol ^-1）和非自发的（在25℃下的ΔG＝96.72kJ mol ^-1）。该催化剂是化学稳定的，并且在铁释放低的情况下可以重复使用。