Calcium Phosphate Nanoparticles Supported on Multi-Walled Carbon Nanotubes for Stabilization of Citrate as a Robust Adsorbent for De-Fluorination
نویسندگان
1 Department of Higher Mathematics, Tashkent University of Information Technologies named after Muhammad Al-Khwarizmi, Tashkent, Uzbekistan
2 Department of Chemical Technology, Navoiy State University of Mining and Technologies, Uzbekistan
3 Department of Functional Products Technology, Tashkent institute of chemical technology, Tashkent, Uzbekistan
4 Tashkent State Technical University, Tashkent, Uzbekistan
5 Department of Orthopedic Dentistry and Orthodontics, Bukhara State Medical Institute Named After Abu Ali Ibn Sino, Bukhara, Uzbekistan
6 Department of Anatomy, Histology and Pathological Anatomy, Tashkent State Medical Institute, Tashkent, Uzbekistan
7 Department of Faculty Therapy, Andijan State Medical Institute, Andijan, Uzbekistan
8 Department of Clinical Sciences, Ma’mun University, Urgench, Uzbekistan
9 Department of Industrial Technology of Medicines, Tashkent Pharmaceutical Institute, Tashkent, Uzbekistan
10 Department of Dermatovenereology and Cosmetology, Samarkand State Medical University, Samarkand, Uzbekistan
11 Department of Endorinology, Hematology and Phthisiology, Fergana Medical Institute of Public Health, Fergana, Uzbekistan
12 Department of Orthopedic Dentistry and Orthodontics, Bukhara State Medical Institute Named After Abu Ali Ibn Sino, Bukhara, Uzbekistan
13 Department of Orthopedic Dentistry and Orthodontics, Bukhara State Medical Institute Named After Abu Ali Ibn Sino, Bukhara, Uzbekistan
doi
10.22052/JNS.2026.02.047چکیده
The development of high-performance adsorbents for fluoride removal remains a significant challenge due to limitations in stability, selectivity, and reusability of existing materials. This study addresses these shortcomings by designing and synthesizing a novel nanocomposite, where citrate-stabilized calcium phosphate (CaP) nanoparticles are anchored onto acid-functionalized multi-walled carbon nanotubes (CaP-Cit@MWCNT). The MWCNT scaffold provides a conductive, high-surface-area support that prevents nanoparticle aggregation, while the citrate ligand plays a dual role: it stabilizes the amorphous CaP phase and presents accessible carboxylate groups for enhanced fluoride binding. Comprehensive characterization confirms the successful formation of the composite, with nanoparticles (~28 nm) uniformly dispersed on the nanotube surface. Batch adsorption studies reveal a maximum capacity of 28.7 mg g⁻¹ (Langmuir model), rapid kinetics best described by a pseudo-second-order model, and optimal performance in the pH 4–7 range. The adsorbent exhibits exceptional selectivity, with minimal interference from chloride or sulfate, though phosphate and bicarbonate present competitive challenges. Crucially, the composite demonstrates promising reusability, retaining 77% of its initial capacity after five regeneration cycles with alkaline desorption. These findings establish CaP-Cit@MWCNT as a robust, regenerable adsorbent, offering a strategic advancement in designing stable nanocomposites for targeted de-fluorination applications in water treatment and dental science.
