Raghav Sapna, Kumar Dinesh
Department of Chemistry, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India.
School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, India.
ACS Omega. 2018 Aug 21;3(8):9675-9688. doi: 10.1021/acsomega.8b01330. eCollection 2018 Aug 31.
This research details the synthesis and application of a novel pectin-hydroxyapatite (PHAp) composite for fluoride (F) adsorption from aqueous solutions. To determine the efficiency of the adsorption process parameters, i.e., adsorbent dose (0.1-0.4 g), initial fluoride concentration (10-30 mg/L), and temperature (298-313 K), the Box-Behnken design with three levels and three factors have been utilized. The quadratic model was established on 27 batch runs by regression analysis of the experimental data of these runs. The efficacy of adsorption was observed using the Langmuir and Freundlich models. The adsorption rate was found at 3.17 mg gmin, and adsorption kinetics followed pseudo-second order (PSO) for PHAp. The significant novelty of this work is the synthesis of unique cubical-shaped rods biopolymer composite from hydroxyapatite. Additionally, this composite showed high adsorption capacity for F compared to other hydroxyapatite adsorbents, and the improved adsorption capacity is attributed to its unique shape which provides a larger surface area. It can be reused for up to six cycles, which makes this method environment-friendly. The economic viability of the synthesized PHAp composite, in comparison to other adsorbents, is evident from the cost-benefit analysis.
本研究详细介绍了一种新型果胶-羟基磷灰石（PHAp）复合材料的合成及其用于从水溶液中吸附氟化物（F）的应用。为了确定吸附过程参数的效率，即吸附剂剂量（0.1 - 0.4 g）、初始氟化物浓度（10 - 30 mg/L）和温度（298 - 313 K），采用了具有三个水平和三个因素的Box-Behnken设计。通过对这27次批次运行的实验数据进行回归分析，建立了二次模型。使用Langmuir和Freundlich模型观察吸附效果。发现PHAp的吸附速率为3.17 mg/g·min，吸附动力学遵循准二级动力学（PSO）。这项工作的显著新颖之处在于由羟基磷灰石合成了独特的立方体形棒状生物聚合物复合材料。此外，与其他羟基磷灰石吸附剂相比，这种复合材料对F表现出高吸附容量，而吸附容量的提高归因于其独特形状提供了更大的表面积。它可以重复使用多达六个循环，这使得该方法对环境友好。与其他吸附剂相比，合成的PHAp复合材料的经济可行性从成本效益分析中显而易见。
