Arsenic emerges out as a potential threat to human health and vegetation in recent past. Therefore, the present study aimed at adsorption of As (V) from the aqueous solution using Fe-AIB and Fe-AIL (iron-impregnated activated carbon synthesized from the powder of bark and leaves of Azadirachta indica tree). The removal of As (V) by Fe-AIB and Fe-AIL was examined under different experimental conditions. The Fe-AIB showed up to 96% As (V) removal at pH of 6.0, and up to 90% removal was observed with Fe-AIL at pH 4.0. Although the kinetic data fit best in the pseudo-second-order model, there are various other processes like intraparticle diffusion, pore diffusion and film diffusion that controls the overall rate. Mechanistic frameworks related to the adsorption process were analysed using various isotherm models. Langmuir and Freundlich models clearly explain As (V) adsorption by Fe-AIB and Fe-AIL. Thermodynamic analysis reveals the spontaneous adsorption on Fe-AIB. Moreover, it also confers the endothermic nature of the adsorption process for both the adsorbents. The presence of co-existing ions like PO₄³⁻ and SiO²₃ negatively interfered the removal or arsenate uptake, whereas ions like SO₄²⁻ and NO₃⁻ do not significantly affect the adsorption process. Consistently greater than 90% As (V) removal up to few cycles for both the adsorbents was observed in regeneration studies. Significant reusability characteristics was possessed by both the spent adsorbents, which makes them potentially efficient for large-scale practical application with enhanced performance.

中文翻译：

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铁浸渍的印A（Azadirachta indica carbon）从水溶液中去除砷（Ⅴ）的动力学平衡和热力学分析

砷最近成为对人类健康和植被的潜在威胁。因此，本研究旨在使用Fe-AIB和Fe-AIL（由印A（Azadirachta indica）的树皮和叶子粉末合成的铁浸渍活性炭，从水溶液中吸附As（V）树）。在不同的实验条件下检查了Fe-AIB和Fe-AIL对As（V）的去除。Fe-AlB在pH值为6.0时显示出高达96％的As（V）去除率，而在pH 4.0时，Fe-AIL去除率高达90％。尽管动力学数据最适合伪二阶模型，但还有其他各种过程（如粒子内扩散，孔扩散和膜扩散）控制着总速率。使用各种等温线模型分析了与吸附过程有关的机制框架。Langmuir和Freundlich模型清楚地解释了Fe-AIB和Fe-AIL对As（V）的吸附。热力学分析揭示了Fe-AIB的自发吸附。而且，它还赋予两种吸附剂吸附过程的吸热性质。PO ₄ ³⁻等共存离子的存在和SiO ² ₃负干扰去除或砷酸摄取，而离子如SO ₄ ^2-和NO ₃ ^-不显著影响吸附过程。在再生研究中，观察到两种吸附剂的去除率始终高于90％As（V）。两种废吸附剂都具有明显的可重复使用特性，这使其对于具有增强性能的大规模实际应用具有潜在的效率。