摘要
对四个吸附铜的坡缕石的解吸附实验研究表明，被解吸附的铜来自于坡缕石的表面和纤维状晶体的网状空隙。吸附铜的坡缕石的X射线光电子能谱（XPS）上出现了932．5eV和933．7eV的光电子峰，表明坡缕石表面的铜以Cu^＋和Cu^2＋的形式存在；傅立叶变换红外吸收光谱（FTIR）上八面体离子的吸收峰出现规律性偏移，其中Mg3OH和Al2□OH吸收峰向高频方向移动了3～5cm^-1，部分铜离子进入到坡缕石的晶体结构的通道中；电子顺磁共振谱上（ESR）出现了g=2．34、2．12、2．08和2．05等4个信号：表明铜离子位于H^＋难以到达的位置。吸附铜的坡缕石的矿物学研究及其解吸附实验的结果均表明铜在坡缕石中以3种形式存在：①以Cu^＋和Cu^2＋的形式吸附在坡缕石纤维的表面，与坡缕石表面的悬空氧成键；②以ECu（H2O）4]^2＋的形式存在于坡缕石的晶体结构的微空腔中（通道）；③以Cu^2＋的形式存在于坡缕石晶体结构中的硅氧四面体六元环的底部或八面体位。
The experiment for desorption of four Cu-adsorbed palygorskites suggests that the leached Cu^2＋ cation is from the surface and net-like interstice of palygorskite. The leached fraction calculated from the quantity of adsorbed and desorbed Cu^2＋ is less than 1%. Four signals, namely g=2.34, 2.12, 2.08, 2.05, are present in the ESR spectra of the palygorskite. This proves that the copper cation takes the position that can not be reached by H＋. The XRD, XPS, FTIR and ESR are employed to study mineralogical characteristics of Cuadsorbed palygorskite. Two photoelectron lines with binding energy of 932.5 and 933. 7eV appear in detailed scan spectra. This means that the valences of copper adsorbed on the surface of palygorskite are ＋ 1 and ＋2. The stretching vibration between the octahedral cation and OH moves about 3- 5 cm ＇ to a higher wavenumber in the FTIR spectra of Cu-adsorbed palygorskite. It can be deduced that the Cu^2＋ is trapped in the channel of the palygorskite. The abovementioned results confirm that copper is adsorbed by palygorskite in three forms. First of all, the copper is adsorbed onto the surface or in net-like interstice of palygorskite and its valences are ＋ 1 and ＋2. Secondly, copper forms a complex ion, [Cu（H2O）4]^2＋, and is trapped in the channel of palygorskite. Finally, copper also enters into a hexagonal hole of tetrahedral or into an octahedral site.
出处
《地质论评》
CAS
CSCD
北大核心
2006年第1期107-112,共6页
Geological Review
基金
国家自然科学基金项目(编号40172016)资助的成果
