Cellulose nanofibers (CNFs) tethered with sulphur as anionic ligand were synthesized from medical absorbent cotton by dissolution with NaOH, CO(NH₂)₂ followed by mechanical intrusion of sulphur from SC(NH₂)₂ at an elevated temperature. The solid-phase CNFs embedded with sulphur complexes possessed negative sites which were used to remove cationic metals viz., Pb(II) and Cd(II) from synthetic and industrial wastewater. The physicochemical properties of the CNFs were analyzed by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), pH at point of zero charge (pH_pzc) and X-ray photoelectron spectroscopy (XPS). Batch adsorption studies were conducted with synthetic wastewater to optimize the conditions for Pb(II) and Cd(II) removal by CNFs. Different adsorption kinetic models were applied to assess and define the adsorption mechanism. The maximum Langmuir adsorption capacity was found to be 1.16 and 0.82 mmol g⁻¹ for Pb(II) and Cd(II) ions, respectively. Regeneration studies showed that the CNFs can be reused using 0.1 M NaOH as eluent. The percentage removal efficiency of different cationic metals by CNFs from untreated industrial wastewater ranged from ca. 90–98%.

通过用NaOH，CO（NH ₂）2溶解，然后在高温下从SC（NH ₂）2机械引入硫，由医用吸收性棉合成与硫作为阴离子配体束缚的纤维素纳米纤维（CNF）。嵌入硫配合物的固相CNF具有负位点，用于从合成和工业废水中去除阳离子金属，即Pb（II）和Cd（II）。通过傅里叶变换红外（FT-IR）光谱，扫描电子显微镜（SEM），零电荷点的pH（pH _pzc）分析了CNF的理化性质）和X射线光电子能谱（XPS）。用合成废水进行分批吸附研究，以优化CNF去除Pb（II）和Cd（II）的条件。应用了不同的吸附动力学模型来评估和定义吸附机理。发现对Pb（II）和Cd（II）离子的最大Langmuir吸附容量分别为1.16和0.82 mmol g ^-1。再生研究表明，使用0.1 M NaOH作为洗脱液可重复使用CNF。CNFs从未经处理的工业废水中去除不同阳离子金属的百分率范围大约为。90–98％。