Umeh Chisom Theresa, Nduka John Kanayochukwu, Akpomie Kovo Godfrey, Obi Amalachukwu Ifeyinwa, Akanbi Nkeiru Magdalene
Environmental Chemistry and Toxicology Research Unit, Pure and Industrial Chemistry Department, Nnamdi Azikiwe University P.M.B 5025 Awka Anambra Nigeria
Department of Pure & Industrial Chemistry, University of Nigeria Nsukka Nigeria.
RSC Adv. 2025 Sep 11;15(39):32942-32955. doi: 10.1039/d5ra05373k. eCollection 2025 Sep 5.
The aquatic environment is being endangered by contamination by organic dyes, which can lead to severe environmental pollution. This study presents the formation of nickel- and copper oxide-loaded (BP) nanocomposites (NiONPs-BP and CuONPs-BP) by a thermo-chemical precipitation process for sequestration of malachite green (MG) dye from a synthetically prepared aqueous solution. The synthesized nanomaterials were examined using FTIR, SEM, XRD, TGA and BET characterization techniques. The findings from the characterization techniques showed the distribution and impregnation of NiO and CuO on BP. The maximum adsorption capacities of NiONPs-BP and CuONPs-BP were 28.77 mg g and 13.66 mg g, respectively. Isotherm and kinetic studies of catalytic MG dye removal are well described by the Freundlich and pseudo-second order models. The NiONPs-BP and CuONPs-BP nanocomposites exhibited higher regression values along with low error compared to BP, and proved better adsorbing materials. The spontaneous nature of MG adsorption was demonstrated by thermodynamic studies. For NiONPs-BP, Δ° > 0 indicated increased disorder at the solid/liquid interface, while Δ° > 0 confirmed the endothermic nature of adsorption. In contrast, adsorption on CuONPs-BP was also accompanied by increased disorder (Δ° > 0) but proceeded through an exothermic process (Δ° < 0). High removal efficiency was recorded after five successive reuse cycles, indicating remarkable stability and reusability of the nanocomposites. Therefore, NiONPs-BP and CuONPs-BP composites were suggested to be efficient adsorbing materials for remediating wastewater polluted with MG dye.
水环境正受到有机染料污染的威胁，这可能导致严重的环境污染。本研究通过热化学沉淀法制备了负载镍和铜氧化物的（BP）纳米复合材料（NiONPs-BP和CuONPs-BP），用于从合成制备的水溶液中螯合孔雀石绿（MG）染料。使用FTIR、SEM、XRD、TGA和BET表征技术对合成的纳米材料进行了检测。表征技术的结果表明NiO和CuO在BP上的分布和浸渍情况。NiONPs-BP和CuONPs-BP的最大吸附容量分别为28.77 mg/g和13.66 mg/g。Freundlich模型和准二级模型很好地描述了催化去除MG染料的等温线和动力学研究。与BP相比，NiONPs-BP和CuONPs-BP纳米复合材料表现出更高的回归值和更低的误差，证明是更好的吸附材料。热力学研究证明了MG吸附的自发性质。对于NiONPs-BP，Δ°>0表明固/液界面的无序度增加，而Δ°>0证实了吸附的吸热性质。相比之下，CuONPs-BP上的吸附也伴随着无序度的增加（Δ°>0），但过程是放热的（Δ°<0）。连续五个重复使用周期后记录到高去除效率，表明纳米复合材料具有显著的稳定性和可重复使用性。因此，建议NiONPs-BP和CuONPs-BP复合材料是修复受MG染料污染废水的有效吸附材料。
