Enemmoh Jennifer N, Harbottle David, Yusuf Muhammad, Hunter Timothy N
School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT UK.
Research Center for Nuclear Materials and Radioactive Waste Technologies (PRTBNLR), Research Organization for Nuclear Energy (ORTN), National Research and Innovation Agency (BRIN), South Tangerang, 15314 Indonesia.
Discov Chem Eng. 2025;5(1):3. doi: 10.1007/s43938-025-00075-y. Epub 2025 Feb 25.
This study investigated combining fine clinoptilolite with iron hydroxide coagulant, as a cost-effective, dual-purpose flocculant for enhanced removal of Pb⁺ or Cu⁺ ions, along with the solid-liquid separation and physicochemical analysis. For the clinoptilolite, adsorption kinetics fitted a pseudo-second-order (PSO) rate model with higher rate constants for Pb, while equilibrium adsorption data fitted the Langmuir monolayer model, with similar at 18.8 mg/g for Pb and 18.3 mg/g Cu. TEM elemental mapping of the clinoptilolite evidenced areas of K and Fe impurities, while SEM suggested a uniform distribution of aggregates comprising a clinoptilolite core with decorated FeOOH. X-ray diffraction (XRD) indicated the FeOOH phase as α-FeOOH (Goethite) with no change in structure on inclusion of adsorbed Pb. Combined clinoptilolite-FeOOH flocs were significantly larger than FeOOH only precipitates, while flocs formed from 0.5 wt% FeOOH and 1 wt% clinoptilolite produced the fastest settling rates and greatest consolidation. Compressive yield stress data also correlated with enhanced dewatering of the combined systems, due to the dense clinoptilolite acting as a weighter material. For final metals removal, combined flocs outperformed FeOOH across a broad concentration range, achieving > 98% removal for both Pb⁺ or Cu⁺. The greater metals removal combined with denser floc production and improved settling features highlights significantly enhanced performance above that possible from either ion exchange or precipitation alone.
The online version contains supplementary material available at 10.1007/s43938-025-00075-y.
本研究调查了将精细斜发沸石与氢氧化铁凝结剂结合，作为一种具有成本效益的双用途絮凝剂，用于增强对Pb⁺或Cu⁺离子的去除，同时进行固液分离和物理化学分析。对于斜发沸石，吸附动力学符合伪二级（PSO）速率模型，Pb的速率常数更高，而平衡吸附数据符合朗缪尔单层模型，Pb的吸附量为18.8 mg/g，Cu的吸附量为18.3 mg/g，两者相近。斜发沸石的透射电子显微镜元素映射证明了K和Fe杂质区域，而扫描电子显微镜表明由斜发沸石核心和装饰的FeOOH组成的聚集体分布均匀。X射线衍射（XRD）表明FeOOH相为α-FeOOH（针铁矿），吸附Pb后结构无变化。斜发沸石-FeOOH复合絮凝物明显大于仅由FeOOH形成的沉淀物，而由0.5 wt% FeOOH和1 wt%斜发沸石形成的絮凝物沉降速度最快，固结性最强。由于致密的斜发沸石作为加重材料，压缩屈服应力数据也与复合系统脱水增强相关。对于最终的金属去除，复合絮凝物在很宽的浓度范围内优于FeOOH，对Pb⁺或Cu⁺的去除率均>98%。更大的金属去除率、更致密的絮凝物产生以及改善的沉降特性突出表明，其性能明显优于单独的离子交换或沉淀。
在线版本包含可在10.1007/s43938-025-00075-y获取的补充材料。
