以D-果糖为炭源,Cu(NO_3)_2为金属前驱体,采用浸渍法结合不同气氛热处理制备了不同价态Cu的CuO_x/C(x=0,1,2)催化剂.实验结果表明:浸渍碳材料后得到的样品经空气250℃热处理5h后Cu以正2价的CuO形式存在;空气热处理后的样品经氢气250℃还原4h后Cu以正1价的Cu_2O形式存在;空气热处理后的样品经氢气300℃还原6h后Cu以0价的Cu单质形式存在.不同价态的铜对于促进H_2O_2分解产生·OH的能力不同.以H_2O_2为氧化剂,乙腈为溶剂,CuO/C催化氧化苯甲醛,表现出较高活性,苯甲酸的产率和选择性分别达到76.2%和99%以上.
Difference Cu valence CuO_x/C(x=0,1,2)catalysts are synthesized through hydrothermal and immersion method with different atmosphere heat-treating by using Cu(NO_3)_2 as copper source and D-fructose as carbon source.Results indicated that the CuOx/C mainly includes Cu~(2+) after heating-treatment for 5h in air atmosphere at 250℃.The CuOx/C mainly includes Cu+after 250℃ hydrogen reduction 4h.The CuOx/C mainly includes Cu after 300 ℃ hydrogen reduction 6h.The abilities of producing·OH by decomposing H_2O_2 are different over different valece state coppr.Using H_2O_2 as oxidant,acetonitrile as solvent,CuO/C as catalyst in benzaldehyde oxidation reaction,the yield of benzoic acid is 76.2%,the selectivity of benzoic acid is greater than 99%.