A new self-assembled cellulose (SACS) containing multi-functional amine, carboxyl and hydroxyl groups was successfully obtained through etherification, cross-linking and grafting processes. Then, the adsorption of sulfamethoxazole (SMZ) and Cd(II) onto SACS at pH values of 3, 5.7 and 7.5 was systematically investigated by batch experiments of single, sequential and binary systems, characterization and density functional theory (DFT) calculations. The presence of Cd(II) decreased the adsorption of SMZ because of hydrophilic site competition, while SMZ inversely increased the adsorption of Cd(II), which was attributed to bridging and especially to electrostatic shielding effects; moreover, both the inhibitory and synergistic effects were more obvious in the binary system and at a pH of 7.5. There was a dynamic balance between the inhibitory and synergistic effects that depended on the system, pH value and concentration ratio. DFT results further indicated that SMZ^- more easily coordinated with Cd(II) at sulfonyl oxygen and nitrogen sites, and the cationic bridge of Cd(II) with SMZ^- mainly occurred in the sequential system. Moreover, a complexation-decomplexation-complexation balance of SMZ^- and Cd(II) probably occurred in the binary system.

通过醚化，交联和接枝过程成功地获得了一种新的含有多功能胺，羧基和羟基的自组装纤维素（SACS）。然后，通过单，序贯和二元体系的批处理实验，表征和密度泛函理论（DFT）计算，系统研究了磺胺甲恶唑（SMZ）和Cd（II）在pH值为3、5.7和7.5时对SACS的吸附。Cd（II）的存在由于亲水位点竞争而降低了SMZ的吸附，而SMZ则反过来增加了Cd（II）的吸附，这归因于桥接，尤其是静电屏蔽效应。此外，在二元体系和pH值为7.5时，抑制作用和协同作用都更加明显。抑制作用和协同作用之间存在动态平衡，这取决于系统，pH值和浓度比。DFT结果进一步表明SMZ^-在磺酰氧和氮位置更容易与Cd（II）配合，Cd（II）与SMZ的阳离子桥^-主要发生在顺序系统中。此外，SMZ的络合-解络络合平衡^-和Cd（II）可能发生在双星系统。