A series of Co-MCM-41 samples with different cobalt contents were synthesized using ascorbic acid as additive and characterized by XRD, low temperature nitrogen adsorption-desorption methods. Cobalt species in/ out of the framework of Co-MCM-41 were extracted by dilute sulfuric acid/concentrated sulfuric acid and determined by chemical analysis methods, respectively. The Co species contents were also estimated by H2-TPR and ICP techniques. The addition of the reductant can improve the orderliness of mesoporous structure of Co-MCM-41s and greatly increase their catalytic activity for the hydroxylation of benzene to phenol.%加入还原剂抗坏血酸合成了一系列高钴含量Co-MCM-41,通过XRD、低温氮吸附-脱附等方法对其介孔结构进行了详细表征.采用以稀硫酸溶解骨架外钴氧化物、再以浓硫酸处理骨架内钴物种,经化学分析方法成功确定了骨架内外钴离子含量和价态,并辅以H2-TPR和ICP方法加以评估.还原剂的加入能够增加Co-MCM-41介孔结构规整度并大幅度提高其在苯羟基化制备苯酚反应中的催化性能.
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