氧化还原聚合物修饰电极用于NO_2^-催化还原的探讨

氧化还原聚合物修饰电极因具有三维反应空间以及多相微结构而具有良好的反应选择性及催化活性。它对由ＧＣ／ＡＱ／Ｏｓ （ｈｐｙ）_（３）^（２－）阳离子交换聚合物及ＰＶＰ阴离子交换聚合物组成的双层聚合物复合修饰电极的电化学特性及对酸性溶液中ＮＯ_２~－的催化还原特性有重要作用。

Low-temperature activity and mechanism of WO_3-modified CeO_2-TiO_2 catalyst under NH_3-NO/NO_2 SCR conditions

The CeO2‐TiO2(CeTi)and CeO2/WO3‐TiO2(CeWTi)catalysts were prepared by a sol‐gel precipitation method and their NH3‐NO/NO2 selective catalytic reduction(SCR)performance was studied.N2O formation and effect of oxygen concentration on SCR performance over CeWTi catalyst were also investigated while varying the NO2/NOx ratio.Results indicate that fast SCR behavior of CeWTi catalyst has the best NH3‐NO/NO2 SCR performance due to the catalyst reoxidation rate by NO2 higher than by O2.Compared with CeTi catalyst,CeWTi catalyst exhibits higher de‐NOx performance under NH3‐NO/NO2 SCR conditions.As the CeTi and CeWTi catalysts exhibit similar redox property,addition of WO3 provides more acid sites which accelerate the reaction between NH4NO3 and NO to get a superior low‐temperature activity.Amount of N2O formation shows a peak at 250 oC mainly derived from NH4NO3 decomposition.

HNO_3催化氧化煤系硫铁矿生产聚铁工艺研究

提出一种以HNO3氧化煤系硫铁矿后产物FeSO4 、H2 SO4 以及补充的FeSO4 和H2 SO4 为原料 ,放出NO为催化剂 ,O2 为氧化剂 ,生产无机净水剂聚铁的生产方法 。

Co/SiO_2催化剂的表征和吸附量热研究

用溶胶-凝胶法制备了Co/S iO2系列的担载型催化剂,采用SBET、TPR、XRD、O2滴定及室温H2、O2、CO和C2H4微量吸附量热等技术进行了研究.结果表明:Co很好分散,S iO2的含量越高,样品的SBET越大;Co是经由Co3+→Co2+→Co0的还原过程;Co/S iO2系列催化剂上,CO、H2、O2和C2H4的初始吸附热数值均比较接近、饱和覆盖度以50Co/50S iO2最高,O2为多层吸附而H2、CO和C2H4为单层吸附,CO为线式吸附并发生歧化反应生成了C和CO2,C2H4吸附解离生成了H2、乙川(C2H3)和C2H6.

全球TiO_2市场货紧价扬

2006年全球TiO2产能约为510万t/a,消费量约为450万t。由于生产成本高和市场需求旺盛,Du-Pont、Millennium化学、Tronox、Huntsman和Kronos等公司都提高价格,增加盈利。2006年日本TiO2产量有所下降,但进口量大增,因此市场仍保持强势。近年来TiO2作为功能材料获得进一步的持续发展,特别是用做超细/纳米材料、电子材料、脱NOx催化剂和光催化剂等应用方面受到愈来愈广泛的关注。