The copper based catalysts, CuO/T-Al2O3, CuO/y-Al2O3-cordierite （Cord） and CuO/Cord, were prepared by impregnation method. The catalytic activity of the catalysts was tested in absence and presence of water vapor,an...The copper based catalysts, CuO/T-Al2O3, CuO/y-Al2O3-cordierite （Cord） and CuO/Cord, were prepared by impregnation method. The catalytic activity of the catalysts was tested in absence and presence of water vapor,and the catalysts were characterized. Temperature program desorption （TPD） experiments or toluene and water on the catalysts were carried out. The influence of water vapor on the activity of the catalysts was discussed. Results showed that addition of the water vapor has a significant negative effect on the catalytic activity of the catalysts.The higher the concentration of the Water vapor in feed steam was, the lower the catalytic activity of the copper based catalysts became, which could be mainly ascribed to the competition of water molecules with toluene molecules for adsorption on the catalyst surfaces. TPD experiments showed that the strength of the interaction between water molecules and three catalysts followed the order： CuO/γ-Al2O3〉CuO/γ-Al2O3-Cord〉CuO/Cord. As a consequence of that, the degree of degradation in the catalytic activity of these three catalysts by the water vapor followed the order： CuO/γ-Al2O3〉CuO/y-Al2O3-Cord〉CuO/Cord. However, the negative effect of the water vapor was reversible.展开更多
为改善Cu基催化剂活性,在确定最佳Cu负载量的基础上,采用冷等离子体技术改性CuO/γ-Al_2O_3催化剂,利用SEM、BET、XRD和XPS技术表征催化剂,研究冷等离子体改性作用对催化剂催化乏风瓦斯燃烧性能的影响。结果表明,Cu的质量分数为7%时,常...为改善Cu基催化剂活性,在确定最佳Cu负载量的基础上,采用冷等离子体技术改性CuO/γ-Al_2O_3催化剂,利用SEM、BET、XRD和XPS技术表征催化剂,研究冷等离子体改性作用对催化剂催化乏风瓦斯燃烧性能的影响。结果表明,Cu的质量分数为7%时,常规催化剂CuO/γ-Al_2O_3催化乏风瓦斯燃烧的活性最强。经等离子体处理后,其催化乏风瓦斯燃烧的特征温度和表观活化能进一步降低。等离子体改性最佳工况条件为放电电压45 k V、放电频率14.71 k Hz、处理时间30 min、氧气空速20 m L/(min·g)。该研究验证了等离子体可通过增大催化剂比表面积和改变孔径、孔容的改性作用,影响乏风瓦斯中甲烷在催化剂表面的吸附、活化和转化。展开更多
A series of metal oxide catalysts for catalytic oxidative degradation of 2-chlorophenol （2-CP） and 4-chlorophenol （4-CP） were prepared, and the supported CuO catalysts were studied particularly. The supported CuO ...A series of metal oxide catalysts for catalytic oxidative degradation of 2-chlorophenol （2-CP） and 4-chlorophenol （4-CP） were prepared, and the supported CuO catalysts were studied particularly. The supported CuO catalysts were characterized by XRD and NH3-TPD techniques, in which CuO/γ-Al2O3 exhibited high degradation activity. The addition of Na2O or K2O into CuO/γ-Al2O3 improved the oxidative degradation of CPs remarkably, in which Na2O was more efficient than K2O. Over CuO/γ-Al2O3-Na2O, CPs were completely converted and the liberation of the inorganic chloride from 2-CP or 4-CP reached 97% or 100% respectively at 30 ？C for 2 h. The supported CuO catalysts with good dispersion of CuO particles and less acid sites were favorable for the efficient oxidative degradation of CPs. In addition, the initial pH of the reaction solution was found to be an important factor which influenced the catalytic oxidative degradation of CPs and the initial pH of 11.2 and 9.8 was preferred for the oxidative degradation of 2-CP and 4-CP respectively over CuO/γ-Al2O3 catalyst.展开更多
基金Supported by the National-Natural Science Foundation of China （20936001）, the Natural Science Foundation of Guangdong Province, and the State Key Lab of Subtropical Building Science, South China University of Technology （x2yj C709028Z）.
文摘The copper based catalysts, CuO/T-Al2O3, CuO/y-Al2O3-cordierite （Cord） and CuO/Cord, were prepared by impregnation method. The catalytic activity of the catalysts was tested in absence and presence of water vapor,and the catalysts were characterized. Temperature program desorption （TPD） experiments or toluene and water on the catalysts were carried out. The influence of water vapor on the activity of the catalysts was discussed. Results showed that addition of the water vapor has a significant negative effect on the catalytic activity of the catalysts.The higher the concentration of the Water vapor in feed steam was, the lower the catalytic activity of the copper based catalysts became, which could be mainly ascribed to the competition of water molecules with toluene molecules for adsorption on the catalyst surfaces. TPD experiments showed that the strength of the interaction between water molecules and three catalysts followed the order： CuO/γ-Al2O3〉CuO/γ-Al2O3-Cord〉CuO/Cord. As a consequence of that, the degree of degradation in the catalytic activity of these three catalysts by the water vapor followed the order： CuO/γ-Al2O3〉CuO/y-Al2O3-Cord〉CuO/Cord. However, the negative effect of the water vapor was reversible.
文摘为改善Cu基催化剂活性,在确定最佳Cu负载量的基础上,采用冷等离子体技术改性CuO/γ-Al_2O_3催化剂,利用SEM、BET、XRD和XPS技术表征催化剂,研究冷等离子体改性作用对催化剂催化乏风瓦斯燃烧性能的影响。结果表明,Cu的质量分数为7%时,常规催化剂CuO/γ-Al_2O_3催化乏风瓦斯燃烧的活性最强。经等离子体处理后,其催化乏风瓦斯燃烧的特征温度和表观活化能进一步降低。等离子体改性最佳工况条件为放电电压45 k V、放电频率14.71 k Hz、处理时间30 min、氧气空速20 m L/(min·g)。该研究验证了等离子体可通过增大催化剂比表面积和改变孔径、孔容的改性作用,影响乏风瓦斯中甲烷在催化剂表面的吸附、活化和转化。
基金financially supported by the Education Department of Liaoning Province(No.2009A421)
文摘A series of metal oxide catalysts for catalytic oxidative degradation of 2-chlorophenol （2-CP） and 4-chlorophenol （4-CP） were prepared, and the supported CuO catalysts were studied particularly. The supported CuO catalysts were characterized by XRD and NH3-TPD techniques, in which CuO/γ-Al2O3 exhibited high degradation activity. The addition of Na2O or K2O into CuO/γ-Al2O3 improved the oxidative degradation of CPs remarkably, in which Na2O was more efficient than K2O. Over CuO/γ-Al2O3-Na2O, CPs were completely converted and the liberation of the inorganic chloride from 2-CP or 4-CP reached 97% or 100% respectively at 30 ？C for 2 h. The supported CuO catalysts with good dispersion of CuO particles and less acid sites were favorable for the efficient oxidative degradation of CPs. In addition, the initial pH of the reaction solution was found to be an important factor which influenced the catalytic oxidative degradation of CPs and the initial pH of 11.2 and 9.8 was preferred for the oxidative degradation of 2-CP and 4-CP respectively over CuO/γ-Al2O3 catalyst.
