Liquid-phase oxidation with hydrogen peroxide of benzyl alcohol and xylenes on Ca₁₀(PO₄)₆(OH)₂ - CaWO₄

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• 作者：Mar&iacute ; a Isabel Dom&iacute ; nguez^a ; Bogdan Cojocaru^b ; Madalina Tudorache^b ; José ; Antonio Odriozola^a ; Miguel Angel Centeno^a ; ^{centeno@icmse.csic.es" class="auth_mail" title="E-mail the corresponding author} ; Vasile I. Parvulescu^b ; ^{vasile.parvulescu@chimie.unibuc.ro" class="auth_mail" title="E-mail the corresponding author}
• 关键词：W-containing apatite ; Liquid phase oxidation of benzyl alcohol and xylenes ; Morphologic characterization of materials
• 刊名：Comptes Rendus Chimie
• 出版年：2016
• 出版时间：October 2016
• 年：2016
• 卷：19
• 期：10
• 页码：1156-1165
• 全文大小：2184 K

文摘

A W-containing apatite (W/HAp) catalyst was prepared following a hydrothermal synthesis route and served as a model catalyst. Crystallographic analysis indicated that the resulting material contained hydroxyapatite, Ca_10−3xW_x(PO₄)₆(OH)₂, W-hydroxyapatite, calcium tungstate, CaWO₄, and tricalcium phosphate, Ca₃(PO₄)₂. The catalyst was investigated in liquid phase oxidation of benzyl alcohol and xylenes using hydrogen peroxide as an oxidant. For comparison, commercial calcium phosphate, hydroxyapatite and CaWO₄ were tested in the same reaction. Calcium phosphate and hydroxyapatite appeared as inactive and decomposed hydrogen peroxide non-selectively. A moderate activity but low hydrogen peroxide efficiency was observed for the CaWO₄ phase. In contrast, the W/HAp catalyst showed a reasonable activity and a better hydrogen peroxide efficiency in the oxidation of benzyl alcohol and xylenes. This new W/HAp catalyst showed, after six cycles, losses of the activity below 15% compared to the fresh catalyst with no effect on the selectivity. It is noteworthy that ICP-OES analyses showed no tungsten leaching that is the main advantage of this catalyst.