以KMnO4为锰源,少量的环己烷为改性剂,采用简易的水热法制备了对照样品(CHM-0)和3种环己烷改性的δ-MnO2(CHM-2,CHM-5和CHM-10).以亚甲基蓝(MB)溶液为模拟染料废水,比较了材料的吸附性能和类Fenton催化性能.采用X射线衍射(XRD)、场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)和N2吸附-脱附等技术对材料进行了表征.利用GC-MS技术对水热反应过程中环己烷的中间氧化产物进行了分析;通过自由基捕获剂实验初步分析了改性δ-MnO2的催化机理,并评价了其稳定性.结果表明,改性δ-MnO2对亚甲基蓝(MB)的吸附性能和催化活性显著提高,且MB的吸附量随着环己烷添加量的增加而增大,而CHM-5的催化活性最高;在水热制备δ-MnO2过程中,环己烷的中间氧化产物有丙酮、环己醇和环己酮;添加环己烷可改变δ-MnO2的形貌与结晶度,CHM-0和CHM-5的比表面积分别为15.9及148.7 {m2/g,} 比表面积的增大提高了δ-MnO2的吸附性能和催化活性;环己烷改性δ-MnO2具有良好的稳定性,其催化H2O2分解主要生成羟基自由基.%Unmodified δ-MnO2(CHM-0) and modified δ-MnO2(CHM-2, CHM-5 and CHM-10) were prepared via a hydrothermal method employing the reaction between KMnO4 and different amounts(0, 2, 5 or 10 mL) of cyclohexane.The products were characterized by X-ray diffraction(XRD), field emission scanning {electron} microscope(FESEM), transmission electron microscopy(TEM) and nitrogen adsorption-desorption measurements.The oxidation products of cyclohexane in the hydrothermal process were identified by gas chromatography-mass spectrometry(GC-MS).Their Fenton-like activity and adsorption capacity for methylene blue(MB) were investigated.The effect of radical scavengers on the degradation of MB was also studied.The {results} indicate that the adsorption capacity of the modified samples increased with increasing the amount of {cyclohexane,} and CHM-5 exhibited the highest catalytic activity.The addition of cyclohexane could modify the morphology and crystallinity of δ-MnO2, and its oxidation products consisted of acetone, cyclohexanol and {cyclohexanone.} The surface area of CHM-5 was 148.7 m2/g, much larger than 15.9 m2/g of CHM-0.{Hydroxyl} radicals were the main active species.
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