催化剂Cu/活性炭分解温度对活性组份铜的化学状态的影响

对浸渍法制得的 Cu(NO_3)_2.3H_2 O/活性炭催化剂前驱态分别在300℃、400℃、500℃,于惰性气体保护下进行热分解,XRD 测定结果表明,分别形成了以 CuO、Cu_2 O、Cu~0 主的物相,并且铜的各种化学状态分布及其比例可通过铜载量和热分解温度进行调节。Cu(NO_3)_2·3H_2 O 在活性炭表面的分散是一活化扩散过程,分解产物 CuO 主要占据表面的能量和几何上有利的位置,如炭的表面含氧功能团和价键不饱和部位。从活性炭的物理化学性质,如炭的还原性能讨论了铜的各种化学状态的形成规律。

Influence of Decomposition Temperature on Chemical States of Copper Active Component on Catalysts Cu/C

Catalyst precursors prepared by impregnating activated carbon in Cu(NO_3)_2·3H_2O solutions of different concentrations were separatively decomposed at 300℃,400℃,500℃ in inert gas.The results of X-ray diffraction indicated that Cu/Ccatalysts were formed with CuO (300℃),Cu_2O (400℃) and CuO (500℃) as themain phase respectively.The various chemical states of copper and their distribu-tion were probably regulated by copper loading content and decomposition tem-perature.The dispersion of Cu(NO_3)_2·3H_2O on the surface of activated carbon wasa process of activated diffusion.The decompositon product CuO occupied primarilypreferable positions of energy and geometry which were oxygen-contained func-tional groups and valence unsaturated spots on the surface of activated carbon.Theformation rules of various chemical states of copper were discussed on the basisof physical and chemical properties of activated carbon such as reduction activity.