Phosphorus (P) adsorption from aqueous solutions is usually evaluated by monitoring the P concentration and employed kinetic models. In this work, three adsorbents obtained from eggshell (ES) and eggshell mixed with palm mesocarp fiber (ESF-1:1 and ESF-1:10) at different Ca(OH)₂/CaCO₃ compositions were evaluated, and the Ca–P species formed monitored as a function of time deconvoluting Fourier Transform Infrared (FTIR) spectra. At 0.25 h the ESF-1:10 (Ca(OH)₂: 26.2 wt%) exhibited better adsorption performance of 35 mgg⁻¹ while ESF-1:1 and ES (Ca(OH)₂: 2.8 and 3.0 wt%) showed 26 and 4 mgg⁻¹, respectively. Characteristic PO₄³⁻ bands in apatite were corroborated by XRD and FTIR. It was found that the role of Ca(OH)₂ in the adsorption ends before 0.25 h, and thereafter CaCO₃ becomes the phase responsible for the removal of orthophosphate H₂PO₄⁻/HPO₄²⁻/PO₄³⁻ ions. The results indicate a direct ligand exchange of CO₃²⁻ for PO₄³⁻ that takes place while increasing the apatite crystallinity. On the other hand, the P adsorption process is also dependent on P concentration. At low P concentrations, characteristic bands of PO₄³⁻ in apatite were observed in FTIR, while at high concentrations, characteristic bands for adsorbed HPO₄²⁻ were obtained. The obtained results give a relevant role to CaCO₃ in P adsorption. Kinetic analysis for Ca-based biocomposites showed that the Avrami order kinetic model fits better for the adsorbents. For P adsorption isotherm process the Langmuir's isotherms showed a good fit, with a maximum adsorption capacity of 90.8, 134.0, and 67.9 mgg⁻¹ for ES, ESF-1:1, and ESF-1:10, respectively.

从水溶液中吸附磷 (P) 通常通过监测 P 浓度和采用的动力学模型来评估。在这项工作中，评估了从蛋壳 (ES) 和蛋壳与棕榈中果皮纤维（ESF-1:1 和 ESF-1:10）在不同 Ca(OH) ₂ /CaCO ₃组成下获得的三种吸附剂，并评估了 Ca–作为时间解卷积傅立叶变换红外 (FTIR) 光谱的函数，监测形成的 P 物质。在 0.25 小时时，ESF-1:10 (Ca(OH) ₂ : 26.2 wt%) 表现出更好的吸附性能，为 35 mg ^-1而 ESF-1:1 和 ES (Ca(OH) ₂ : 2.8 和 3.0 wt%)分别显示 26 和 4 mg ^-1。特性 PO ₄ ³⁻磷灰石中的谱带通过 XRD 和 FTIR 得到证实。发现Ca(OH) ₂在吸附中的作用在0.25小时前结束，此后CaCO ₃成为负责去除正磷酸盐H ₂ PO ₄ ^- /HPO ₄ ^2- /PO ₄ ^3-离子的相。结果表明CO ₃ ^2-与PO ₄ ^3-的直接配体交换发生在增加磷灰石结晶度的同时。另一方面，P 吸附过程也依赖于 P 浓度。在低 P 浓度下，PO ₄ ^{3− 的}特征带在 FTIR 中观察到磷灰石中的 , 而在高浓度下,获得了吸附 HPO ₄ ^{2- 的}特征带。获得的结果给出了CaCO ₃在P吸附中的相关作用。Ca 基生物复合材料的动力学分析表明，Avrami 有序动力学模型更适合吸附剂。对于 P 吸附等温线过程，Langmuir 等温线显示出良好的拟合，ES、ESF-1:1 和 ESF-1:10的最大吸附容量分别为 90.8、134.0 和 67.9 mg ^-1。