Nano‐hydroxyapatite (NHAp) with a novel rod shape was synthesized from an economical and easily accessible Labeo rohita fish scale bio‐waste by facile and straightforward alkaline heat treatment method. The purity, functionality, morphology, and surface area of the green synthesized NHAp powder were well‐characterized via X‐ray diffraction (XRD), Fourier‐transform infrared (FT‐IR) spectroscopy, transmission electron microscopy (TEM), and Brunauer‐Emmett‐Teller (BET). The TEM and BET results indicate that the apatite is prepared as a rod‐like particle and highly porous with high surface area (112.36 m² g⁻¹). The NHAp powder was used for the adsorptive removal of cationic dye‐methylene blue (MB) from the aqueous samples. Batch experiments were performed to evaluate the mechanism of adsorption and kinetic models. The NHAp achieved an enhanced adsorption efficiency (666.67 mg g⁻¹) for the adsorption process. The obtained results perfectly obeyed the pseudo‐second‐order model, and the Langmuir isotherm exhibited an excellent relationship with the experimental data. Furthermore, thermodynamic studies reveal that the adsorption process was exothermic and spontaneous. Thus, the results proved that Labeo rohita fish scale bio‐waste derived NHAp can be inventively utilized as a cost‐effective and eco‐friendly adsorbent for wastewater treatment.

中文翻译：

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利用鱼鳞生物废料合成的纳米羟基磷灰石有效去除阳离子亚甲基蓝染料

纳米棒状纳米磷灰石（NHAp）是通过经济，易于获得的Labeo rohita鱼鳞生物废料，通过简便而直接的碱性热处理方法合成的。通过X射线衍射（XRD），傅立叶变换红外（FT-IR）光谱，透射电子显微镜（TEM）和Brunauer-埃米尔特勒（BET）。TEM和BET结果表明，磷灰石为棒状颗粒，具有高孔隙率，高表面积（112.36 m ² g ^-1）。NHAp粉末用于从水性样品中吸附去除阳离子染料-亚甲基蓝（MB）。进行批处理实验以评估吸附和动力学模型的机理。NHAp在吸附过程中实现了更高的吸附效率（666.67 mg g ^-1）。获得的结果完全服从伪二阶模型，Langmuir等温线与实验数据显示出极好的关系。此外，热力学研究表明吸附过程是放热的和自发的。因此，结果证明，Labeo rohita鱼鳞生物废料衍生的NHAp可以创造性地用作废水处理的经济高效且生态友好的吸附剂。