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首先将商用活性炭样品在1%的稀硝酸中处理,然后等体积浸渍在含有5%和10%(质量分数)硝酸钴、硝酸镍或硝酸铜的水溶液中,并在100℃干燥至恒重,最后将样品在Ar气氛中于400℃焙烧3 h.采用X射线衍射、N2吸附和红外光谱等分析手段对不同固体样品进行了表征,并考察了其对异丙醇催化转化和25~45℃时过氧化氢催化分解的活性.结果表明,掺杂5%或10%的过渡金属氧化物后,活性炭样品中含有结晶度很差的CoO,Co3O4,NiO,Cu2O和CuO相的纳米晶.金属氧化物预处理使活性炭的BET比表面积略有增加.这些固体样品主要用作脱氢催化剂,其选择性均高于90%.在225℃时,经5%氧化钴、氧化镍和氧化铜处理的活性炭的催化活性比硝酸处理的活性炭分别提高了6%,24.6%和40.6%.少量CoO处理后的商用活性炭对H2O2催化分解活性的提高是由参与该催化反应的活性位浓度的显著增加而引起的,该处理过程并没有改变H2O2催化分解的机理.
Commercial activated carbon samples are first treated in 1% dilute nitric acid and then soaked in an equal volume of aqueous solution containing 5% and 10% (mass fraction) cobalt nitrate, nickel nitrate or copper nitrate and dried at 100 ° C until constant weight, Finally, the sample was calcined at 400 ℃ for 3 h in Ar atmosphere.The solid samples were characterized by X-ray diffraction, N2 adsorption and infrared spectroscopy, and their catalytic performance for isopropanol conversion and 25 ~ 45 ℃ The results showed that the activated carbon samples contained nanocrystals of CoO, Co3O4, NiO, Cu2O and CuO with poor crystallinity after doped with 5% or 10% transition metal oxides. Oxide pretreatment gave a slight increase in the BET specific surface area of the activated carbon.These solid samples were mainly used as dehydrogenation catalysts with selectivity higher than 90% .They were treated with 5% cobalt oxide, nickel oxide and copper oxide at 225 ℃ Of the activated carbon was 6%, 24.6% and 40.6% higher than that of the nitric acid treated activated carbon respectively.A small amount of commercial activated carbon after the CoO treatment increased the catalytic activity of H2O2 by a significant increase in the concentration of active sites involved in the catalytic reaction Caused by the process did not Have to change the mechanism of H2O2 catalytic decomposition.