This study evaluated the adsorption of Cr⁶⁺ from aqueous solution using dead biomass of aquatic plants Salvinia molesta (Kariba weed) and Typha latifolia (broadleaf cattail). The batch experiments were carried out to study the effects of pH, adsorbent dose, initial metal concentration, contact time, agitation speed in rotation per minute (rpm), and temperature. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize the adsorbent and analyze the functional groups and morphology of the adsorbent, respectively. The hydroxyl and amine groups were the main functional groups involved in the adsorption. Both adsorbents showed good results at pH 1, metal concentration of 20 mg/L for Cr⁶⁺ removal, and adsorption equilibrium was attained within 60 min with 150 rpm at 25 °C. The adsorption rate obtained was above 95% for both the adsorbents at a dose of 0.150 g for S. molesta and 0.8 g for T. latifolia. Isotherm and kinetic models were applied on the adsorption data. The monolayer adsorption capacity (q_m) was found to be 33.33 mg/g for S. molesta and 10.30 mg/g for T. latifolia. The Langmuir isotherm was better fitted to S. molesta, while the Freundlich isotherm was better fitted to T. latifolia. It was reported that the pseudo-second-order model (R² = 0.999) was better fitted to the adsorption data for both the adsorbents. The thermodynamic study was also conducted and found the adsorption process was exothermic and spontaneous. Results revealed the good adsorption potential of S. molesta and T. latifolia, and they can be used for the removal of hexavalent chromium.

本研究使用水生植物鼠尾草（Kariba 杂草）和香蒲（阔叶香蒲）的死生物量评估了从水溶液中吸附 Cr ^{6+ 的情况}。进行分批实验以研究 pH、吸附剂剂量、初始金属浓度、接触时间、每分钟旋转搅拌速度 (rpm) 和温度的影响。傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）分别用于表征吸附剂并分析吸附剂的官能团和形貌。羟基和胺基是参与吸附的主要官能团。两种吸附剂在 pH 值为 1、金属浓度为 20 mg/L 的 Cr ^{6+ 条件下}均显示出良好的结果去除，并在 25°C 下以 150 rpm 的转速在 60 分钟内达到吸附平衡。得到的吸附率为95％，持续两个以上吸附剂的剂量0.150克为S.食心虫和0.8g为T. latifolia的。等温线和动力学模型应用于吸附数据。发现单层吸附容量 ( q _m ) 为 33.33 mg/g 对S. moolesta和 10.30 mg/g 对T. latifolia。Langmuir 等温线更适合S.moleta，而 Freundlich 等温线更适合T. latifolia。据报道，伪二阶模型（R ² = 0.999) 更适合两种吸附剂的吸附数据。还进行了热力学研究，发现吸附过程是放热和自发的。结果显示的良好的吸附电位S.食心虫和T. latifolia的，并且它们可以被用于去除六价铬。