论文部分内容阅读
对在ｐＨ ≤４．５、痕量浓度条件下吸附了Ｃｕ~（２＋）的蒙脱石的Ｘ射线衍射（ＸＲＤ）进行了研究。该蒙脱石的ｄ（００１） 由原始蒙脱石的１．４７９ ｕｍ变为 １．５２３ ｕｍ，说明水合铜离子置换了蒙脱石的层间阳离子；在该蒙脱石的 ＥＰＲ谱中记 录到了 ｇ＝ ２． ０７、 ｇ＝ ２． １４精细结构线和 ｇ为约 ２． ７～ ２． ２超精细结构线三组有关 Ｃｕ~（２＋）的信号，说明其中的 Ｃｕ~（２＋）有 三种不同的结构状态。同时，该蒙脱石热处理产物的 ＥＰＲ研究表明， ｇ＝ ２． １４信号与蒙脱石层间的水合铜离子相关， ｇ＝ ２． ０７信号和 ｇ为约 ２． ７～ ２． ２超精细结构线分别与进入了粘土矿物Ｓｉ－Ｏ四面体片复三方形孔洞和铝氧八面体空位中的 Ｃｕ~（２＋）相关。整个研究表明，在 ｐＨ ≤ ４． ５、痕量浓度条件下，蒙脱石对 Ｃｕ~（２＋）的吸附包括两种方式，即交换吸附和专性吸附。
X-ray diffraction (XRD) of montmorillonite with Cu 2+ adsorbed at a trace concentration of pH ≤4.5 was studied. The d (001) of the montmorillonite changed from 1.479 um of the original montmorillonite to 1.523 um, indicating that the cupric ions replaced the interlayer cations of montmorillonite; the EPR spectrum of the montmorillonite was recorded To g = 2. 07, g = 2. 14 fine structure lines and g is about 2. 7 ~ 2. 3 superfine structure of the three groups of signals on Cu ~ (2+), indicating that there are three different Cu ~ (2+) structure state. Meanwhile, the EPR study of the montmorillonite heat-treated product showed that g = 2. 14 Signals are related to hydrated copper ions between smectites, g = 2. 07 signal and g is about 2. 7 ~ 2. 2 hyperfine structure lines are respectively associated with Cu 2+ in the complex trihedral and aluminum-octahedra vacancies into the Si-O tetrahedra of clay minerals. The entire study showed that at pH ≤ 4. Under the condition of trace concentration, the adsorption of Cu 2+ by montmorillonite includes two ways: exchange adsorption and specific adsorption.