摘要
对Cr3+,Cr6+在累托石、三甲基十八烷基氯化铵交联累托石(简称有机累托石)表面的吸附作用进行研究表明:累托石对Cr3+有良好的吸附作用,而对Cr6+的吸附效果很差;有机累托石对Cr3+和Cr6+,均表现出优良的吸附性能,说明Cr3+可以交换间层的Ca2+而存在于累托石的层间,而Cr6+由于形成半径大的水合离子团而难以进入累托石的层间。XRD结果表明,Cr3+和Cr6+反应的累托石的(001)间距分别为2.5080nm和2.4798nm,与反应前累托石的(001)间距2.5368nm基本一致;有机累托石的(001)间距为4.0124nm,Cr3+和Cr6+反应有机累托石的(001)间距分别变为3.5595nm和3.6477nm,由于在有机累托石的层间,Cr3+,Cr6+与硅氧四面体层的相互作用,导致层间作用力增大而层间距减小。与Cr3+,Cr6+的反应直接影响累托石硅氧四面体层中硅氧键的红外吸收谱带的位置与强度,说明Cr3+,Cr6+与硅氧四面体层中硅氧表面成键。
Investigations on adsorption of Cr ( Ⅲ ), Cr ( Ⅵ ) onto rectorite and organic rectorite have been undertaken by using inductively coupled plasma atomic emission spectrometer, X-ray powder diffraction and infrared absorption spectrometry. The results show that rectorite can efficiently remove Cr ( Ⅲ ), instead of Cr ( Ⅵ ), from solution, while organic rectorite can efficiently remove both of the catons from solutions, suggesting that Cr ( Ⅲ ) may replace the interlayer Ca^2+ ,Cr( Ⅲ ) can not enter the interlayer space for its larger hydrated radius, and the interlayer space of the organic rectorite is, however, large enough to uptake both the Cr( Ⅲ ) and Cr(Ⅵ ). The (001)spacing of the rectorite, the Cr( Ⅲ ) -rectorite, and the Cr(Ⅵ)-rectorite are 2. 536 8 nm,2. 508 0 nm,and 2. 479 8 nm respectively, and those of the organic rectorite, Cr( Ⅲ ) -organic-rectorite, and Cr(Ⅵ ) -organic-rectorite are 4. 012 4 nm,3. 559 5 nm and 3. 647 7 nm, respectively, indicating that the strong chemical interaction between Cr( Ⅲ ) or Cr( Ⅵ ) and the surface of the SiO4 tetrahedral sheet lead to the shortening of the(001)spacing, and result in the variation in adsorption positions and intensity of Si- O bond in the SiO4 tetrahedral sheet.
出处
《矿物岩石》
CAS
CSCD
北大核心
2005年第4期1-5,共5页
Mineralogy and Petrology
基金
国家自然科学基金(40172017)