Abstract Adipic acid dihydrazide (ADH) was used to cross-link carboxymethyl chitosan (CMCS) microspheres for Cu 2+ removal from aqueous solution. SEM, FTIR, XPS and BET techniques were performed to characterize the ADH cross-linked CMCS (ADH-CMCS) microspheres. The effects on adsorption capacities of pH value, adsorption time, and initial Cu 2+ concentration were investigated. The adsorption experiments demonstrated ADH-CMCS microspheres had high adsorption capacity for Cu 2+ removal. Furthermore, in order to investigate the effect of ADH in ADH-CMCS microspheres on Cu 2+ adsorption, cross-linking experiments and XPS tests were carried out to reveal the adsorption mechanism. The results suggested that ADH in ADH-CMCS microspheres had a compensation action on its consumption of binding sites for Cu 2+ adsorption. The XPS etching results showed cross-linking reaction occurred mainly on the surfaces of the microspheres. The kinetics of Cu 2+ adsorption on ADH-CMCS microspheres complied with the pseudo-second-order model, indicating a chemical reaction process. The adsorption data analysis using three different adsorption isotherm models indicated that ADH-CMCS microspheres were of heterogeneity surfaces. Moreover, the ADH-CMCS microspheres still exhibited good adsorption performances after the fifth adsorption-desorption cycle.

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铜离子吸附己二酸二酰肼交联羧甲基壳聚糖微球的制备及评价

摘要 己二酸二酰肼 (ADH) 用于交联羧甲基壳聚糖 (CMCS) 微球以去除水溶液中的 Cu 2+ 。使用 SEM、FTIR、XPS 和 BET 技术来表征 ADH 交联的 CMCS (ADH-CMCS) 微球。研究了pH值、吸附时间和初始Cu 2+ 浓度对吸附容量的影响。吸附实验表明ADH-CMCS微球对Cu 2+ 去除具有高吸附能力。此外，为了研究ADH在ADH-CMCS微球中对Cu 2+ 吸附的影响，进行了交联实验和XPS测试以揭示吸附机理。结果表明ADH-CMCS微球中的ADH对其Cu 2+ 吸附结合位点的消耗具有补偿作用。XPS 蚀刻结果表明交联反应主要发生在微球表面。Cu 2+ 在ADH-CMCS微球上的吸附动力学符合准二级模型，表明是化学反应过程。使用三种不同吸附等温线模型的吸附数据分析表明，ADH-CMCS 微球具有异质表面。此外，经过第五次吸附-解吸循环后，ADH-CMCS微球仍表现出良好的吸附性能。使用三种不同吸附等温线模型的吸附数据分析表明，ADH-CMCS 微球具有异质表面。此外，经过第五次吸附-解吸循环后，ADH-CMCS微球仍表现出良好的吸附性能。使用三种不同吸附等温线模型的吸附数据分析表明，ADH-CMCS 微球具有异质表面。此外，经过第五次吸附-解吸循环后，ADH-CMCS微球仍表现出良好的吸附性能。