In this study, sepiolite was modified by calcination (200 °C) and cetyltrimethylammonium bromide (CTMAB) treatment. Though the specific surface area sharply declined, the adsorption amount of Acid Orange II (AO), Reactive Blue (RB), Acid Fuchsin (AR) and their mixed solution were improved. The morphology of modified sepiolite showed a better dispersibility and looser structure. The adsorption performance was highly impacted by the pH condition and adsorbent dosage. The electrostatic attraction of positively charged adsorption sites on the adsorbent surface and the negatively charged anionic dye could enhance the adsorption amount especially under acid condition. The order of preferentially adsorbed dye was AO > RB > AR. The adsorption process was much correlated to the quasi-second-order reaction kinetics. The adsorption amount and equilibrium amount of single dye system, as well as in the mixed system were in accordance with the Langmuir model and extended Langmuir isotherm.

中文翻译：

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十六烷基三甲基溴化铵改性海泡石对混合染料体系的吸附：表征、性能、动力学和热力学

在这项研究中，海泡石通过煅烧 (200 °C) 和十六烷基三甲基溴化铵 (CTMAB) 处理进行改性。虽然比表面积急剧下降，但酸性橙II（AO）、活性蓝（RB）、酸性品红（AR）及其混合溶液的吸附量有所提高。改性海泡石的形态表现出更好的分散性和更松散的结构。吸附性能受pH条件和吸附剂用量的影响很大。吸附剂表面带正电荷的吸附位点和带负电荷的阴离子染料之间的静电引力可以提高吸附量，尤其是在酸性条件下。优先吸附染料的顺序是AO > RB > AR。吸附过程与准二级反应动力学密切相关。