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本工作对Cd(Ⅱ)在多孔六方氮化硼(p-BN)上的吸附行为和机理进行了系统而全面的研究,考察了溶液pH、吸附剂用量、接触时间和温度等条件对于Cd(Ⅱ)吸附的影响,并采用不同手段表征了吸附前后p-BN的化学组成、形态和表面官能团的变化,进而研究其吸附机理.研究结果显示,在pH 7.0和313 K条件下,Cd(Ⅱ)的最大吸附容量可达到184 mg·g–1,其动力学数据与拟二级模型和颗粒内扩散模型吻合,表明吸附主要受化学吸附控制,限速步骤主要是分子扩散.Cd(Ⅱ)在p-BN上的吸附是一个自发和吸热过程,吸附等温线分别符合Freundlich和Langmuir模型,说明Cd(Ⅱ)通过多层和单层吸附而吸附在非均相表面上.XPS的光谱结果显示,p-BN吸附剂具有大量的B–N,B–O等结构用作键合位点,有利于从废水中吸收Cd(Ⅱ).这些结果表明,p-BN有希望作为吸附材料用于清除水体中的Cd(Ⅱ).“,”In present work, a systematical and comprehensive understanding for the adsorption of Cd(Ⅱ) on porous hexagonal boron nitride (p-BN) was studied. The chemical compositions, morphology and surface functional groups of p-BN before and after adsorption were characterized by SEM, HRTEM, BET, XRD, and FT-IR. The effects of pH, adsorbent dosage, contact time and temperature on Cd(Ⅱ) adsorption were investigated. The maximum adsorption capacity for Cd(Ⅱ) achieves 184 mg·g–1 at pH 7.0 and 313 K. The kinetic data fitted well with pseudo-second-order model and intra-particle diffusion model, indicating that the adsorption is mainly controlled by chemisorption, and the rate-limiting step is the molecular diffusion. The adsorption isotherms are in accordance with Freundlich and Langmuir model respectively, suggesting Cd(Ⅱ) adsorbed on the heterogeneous surface through multilayer and monolayer adsorption. The thermodynamic parameters are calculated to confirm the spontaneous and endothermic process of Cd(Ⅱ) sorption. Spectroscopic results from XPS imply that p-BN adsorbent had substantial functional groups and bonding sites, which is propitious to uptake Cd(Ⅱ) from wastewater. These results revealed that p-BN is a promising candidate for Cd(Ⅱ) scavenging.