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由于柱状和薄层状粘土独特的极性、孔粒分布和高比表面积,因而是一种潜在的吸附环境毒物的有用物质。为测定其对氯化苯酚的吸附性能,将铝-柱状蒙脱石(APM)、铬-柱状蒙脱石(CPM)和铝-薄层状锂皂石(ADL)与五氯苯酚(PCP)反应进行了间歇平衡试验。研究包括一种羟基铝锂皂石(HAL),其中的交换阳离子Na~+的替换形式为:Al_(13)O_4(OH)_(24+x)(H_2O)_(2-x)~(7-x)~+。用ADL作吸附剂,对PCP的吸附能力随pH值的降低而增大,当pH≤pKa时达到稳定,因此最先选择的是中性氯而不是酚盐。当pH=4.7时,中性PCP与所有的吸附剂配合使用均未得到满意的结果,这是由于受吸附物在水中的溶解能力限制而未能达到饱和所致。在所研究的柱状和薄层状粘土中,pH=4.7时,ADL对PCP的物理吸附能力最大。由于PCP对APM、CPM和ADL的粘附能力不同,因而认为吸附作用依赖于改良粘土吸附剂的孔状结构和表面组分而不仅仅依赖于表面积。当PCP为8μmol/g时,HAL对PCP的定量吸附表明这种吸附可能是化学选择的结果。pH为7.4时,ADL对3-氯苯酚、3,5-二氯苯酚和3,4,5-三氯苯酚的吸附随苯酚疏水性和氯化作用程度的增加而增加。由此可见吸附能力并不受吸附物分子大小的限制。与吸附性质相反,柱状、薄层状和羟基一间层粘土——Na~+蒙脱石和Na~+锂皂石不会从水溶液中吸附PCP。
Due to the unique polarity, pore size distribution and high specific surface area of columnar and lamellar clays, it is a potentially useful substance for the absorption of environmental poisons. In order to determine its adsorption capacity to chlorinated phenol, aluminum-montmorillonite (APM), chromium-montmorillonite (CPM) and aluminum-lamella laponite (ADL) and pentachlorophenol (PCP) The reaction was intermittently equilibrated. The study includes a kind of aluminum hectorite (HAL), in which the exchangeable Na ~ + is replaced by Al_ (13) O_4 (OH) _ (24 + x) (H_2O) _ (2-x) 7-x) ~ +. With ADL as adsorbent, the adsorption capacity of PCP increases with the decrease of pH value, and when pH≤pKa, the adsorption is stable, so the first choice is neutral chlorine instead of phenate. When pH = 4.7, the neutral PCP with all the adsorbents did not get satisfactory results, which is due to the ability of the adsorbate in the water to dissolve the ability to fail to reach saturation. In the studied columnar and lamellar clays, ADL has the greatest physical adsorption capacity for PCP at pH = 4.7. Due to the different adherability of PCP to APM, CPM and ADL, adsorption is believed to depend on the pore structure and surface composition of the modified clay adsorbent and not only on the surface area. Quantitative adsorption of PCP by HAL at a PCP of 8 μmol / g suggests that this adsorption may be the result of a chemical selection. Adsorption of 3-chlorophenol, 3,5-dichlorophenol and 3,4,5-trichlorophenol by ADL increased with the increase of phenol hydrophobicity and chlorination at pH 7.4. This shows that the adsorption capacity is not limited by the size of the adsorbate molecules. In contrast to the adsorption properties, columnar, lamellar and hydroxy-layered clays - Na ~ + montmorillonite and Na ~ + laponite do not adsorb PCP from aqueous solutions.