Fathy Aya T, Moneim Mohamed A, Ahmed Ezzat A, El-Ayaat Abdalla M, Dardir Fatma M
Geology Department, Faculty of Science, Assiut University, Assiut, Egypt.
Sci Rep. 2025 Jan 11;15(1):1680. doi: 10.1038/s41598-024-82861-2.
Limestone mining waste and its derived CaO were checked as an adsorbents of pb, Cu, and Cd ions from water solution. The characterization of Limestone and calcined limestone was studied by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), and Surface area measurements (BET). The optimum conditions of sorbent dosage, pH, initial concentration, and contact time factors were investigated for pristine limestone and calcined limestone absorbents. The results indicate that the optimum initial concentrations of (C) were 1200, 500, and 300 ppm for Pb, Cu, and Cd, respectively, using calcined limestone adsorbent, while using the pristine limestone adsorbent, the corresponding optimum initial concentrations were 700, 110, and 50 ppm. In the ternary system sorption, the results indicated that the selectivity sequence of the studied metals by limestone can be expressed as Pb > Cd > Cu, while calcined limestone exhibits a higher selectivity for Pb compared to Cu and Cd. Hence, various adsorption isotherm and kinetic models were examined to explore different patterns and behaviors of adsorption. So, the results indicate that calcined limestone has great potential for eliminating cationic heavy metal species from industrial water solutions.
对石灰石采矿废料及其衍生的氧化钙作为水溶液中铅、铜和镉离子吸附剂进行了检测。采用X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）、热重分析（TGA）、扫描电子显微镜（SEM）和表面积测量（BET）对石灰石和煅烧石灰石进行了表征。研究了原始石灰石和煅烧石灰石吸附剂的吸附剂用量、pH值、初始浓度和接触时间等因素的最佳条件。结果表明，使用煅烧石灰石吸附剂时，铅、铜和镉的最佳初始浓度分别为1200、500和300 ppm，而使用原始石灰石吸附剂时，相应的最佳初始浓度分别为700、110和50 ppm。在三元体系吸附中，结果表明石灰石对所研究金属的选择性顺序为Pb＞Cd＞Cu，而煅烧石灰石对Pb的选择性高于Cu和Cd。因此，研究了各种吸附等温线和动力学模型，以探索不同的吸附模式和行为。所以，结果表明煅烧石灰石在去除工业水溶液中阳离子重金属物种方面具有巨大潜力。
