The sulfonated covalent organic frameworks (COF@SO₃H) have been synthesized by a simple one-step solvothermal reaction and used to adsorb Cd²⁺, Co²⁺, and Cr³⁺ metal ions from aqueous solution. The structure, composition and stability of as-prepared material were confirmed by FT-IR, PXRD, BET and TGA, and a fiber bundle-like COF@SO₃H could be observed in the SEM and TEM images. The adsorption behaviors of Cd²⁺, Co²⁺, and Cr³⁺ onto COF@SO₃H were studied through batch adsorption experiments, and the obtained data were analyzed using various models. The adsorption process of the three ions can be better described by the Langmuir isotherm and the pseudo-second-order kinetics than other models tested, and the maximum adsorption capacities for Cd²⁺, Co²⁺ and Cr³⁺ at 298 K are 81.97, 77.52, and 105.26 mg g⁻¹, respectively. The thermodynamic parameters indicate that the adsorption of Cd²⁺ onto COF@SO₃H is spontaneous, which is more favorable than Co²⁺ and Cr³⁺. Moreover, the adsorbed metal ions can be easily eluted by nitric acid or EDTA solution, and the COF@SO₃H can be reused for more than 5 adsorption-elution cycles without obvious collapsing in structure and reducing in adsorption capacity. All the results suggested that the COF@SO₃H could be used to the adsorption and removal of heavy metal ions from wastewater.

磺化的共价有机骨架（COF @ SO ₃ H）是通过简单的一步溶剂热反应合成的，并用于从水溶液中吸附Cd 2 ⁺，Co ²⁺和Cr ³⁺金属离子。所制备的材料的结构，组合物和稳定性，通过FT-IR，PXRD，BET和TGA，和纤维确认束状COF @ SO ₃ h后在SEM和TEM图像中观察到。Cd 2 ⁺，Co ²⁺和Cr ³⁺在COF @ SO ₃上的吸附行为通过分批吸附实验研究了H，并使用各种模型对获得的数据进行了分析。朗格缪尔等温线和拟二级动力学可以较好地描述三种离子的吸附过程，并且在298 K下对Cd 2 ⁺，Co ²⁺和Cr ³⁺的最大吸附容量为81.97。分别为77.52和105.26 mg g ^-1。热力学参数表明，Cd ²⁺在COF @ SO ₃ H上的吸附是自发的，比Co ²⁺和Cr ³⁺更有利。而且，吸附的金属离子很容易被硝酸或EDTA溶液洗脱，COF @ SO₃ H可以重复使用5个以上的吸附-洗脱循环，而不会出现明显的结构塌陷和吸附容量降低的情况。所有结果表明，COF @ SO ₃ H可用于废水中重金属离子的吸附和去除。