赵思雨和王泽宇:求助：翻译

Na-clays carry a permanent negative charge in their structural framework. The hydration of Na+ ions in clays and the nature of Si-O groups impart a hydrophilic nature to the mineral surfaces. Because of this property, water is preferentially adsorbed by these surfaces, and large organic compounds cannot compete with strongly held water for adsorption sites on the clay surfaces. Thus, Na-clays are ine_ective sorbents for small organic molecules. However, it is possible to modify the surface properties of clays greatly by neutralizing the anionic framework of layer silicates by using positively charged organic species such as alkylammonim ions. In the modified form (HDTMA-bentonite), the clay surface may become organophilic and interact strongly with organic compounds. Textile dyes represent a relatively large group of organic chemicals. In an HDTMA-bentonite-dye system it is possible that adsorption may be enhanced by the hydrophobic interaction between the adsorbed dye molecule and HDTMA-bentonite. The interlamellar spacing of the HDTMA-bentonite was obtained by substracting the thickness of the clay layer from the experimentally determined basal spacing (d001). The intercalation of the HDTMA cation increased the interlamellar distances from 13.2A (Na-bentonite) to 17.9A (HDTMA-bentonite). The larger basal spacing (d001) of HDTMA-bentonite corresponds to the formation of bilayers in which the long-chained surfactant cations are in direct contact with each other10, leading to the formation of organic phases consisting mostly of the C16 hydrocarbon groups into which solutes are partitioned. Thus, the degree of sorption of dyes depends on the amount of the surfactant ions in the bentonite interlayer sites.