Bimetallic nanoparticles comprised of iron and nickel were synthesized, characterized, and evaluated to optimize the ideal metal ratio for azo dye removal from water systems. Results show that changing the molar ratio of nickel to iron caused different removal rates, as well as the extent of overall elimination of azo dye from water. Lower molar ratios, from Ni ₁ Fe ₁₀ to Ni _2.5 Fe ₁₀ , exhibited a higher removal efficiency of 80–99%. Higher concentrations of Ni in the catalyst, from Ni ₃ Fe ₁₀ to Ni ₅ Fe ₁₀ , resulted in 70–90% removal. The lower molar ratios of Ni exhibited a consistent removal rate of 0.11 g/L/min, while the higher molar ratios of Ni displayed varying removal rates of 0.1–0.05 g/L/min. A second order kinetic model was fit to the first twenty minutes of the reaction for all nickel to iron compositions, where there is a decrease in rate constant with an increase in molar ratio. During the last forty minutes of reaction, azo dye removal fit a zero order kinetic model. All as-synthesized nanoparticle samples were found to be structurally disordered based on the lack of distinct peaks in XRD spectra. Post-reaction samples were found to have Fe ₂ O ₃ and FeOOH cubic peaks.

中文翻译：

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镍-铁合金纳米粒子与橙G的反应前后特征

合成，表征和评估了由铁和镍组成的双金属纳米粒子，以优化用于从水系统中去除偶氮染料的理想金属比。结果表明，改变镍与铁的摩尔比会导致不同的去除率，以及从水中整体去除偶氮染料的程度。从Ni ₁ Fe ₁₀到Ni _2.5 Fe _10的较低摩尔比 显示出80-99％的较高去除率。催化剂中较高的Ni浓度，从Ni ₃ Fe ₁₀到Ni ₅ Fe ₁₀ ，导致去除率达70–90％。较低的镍摩尔比显示出一致的去除速率为0.11 g / L / min，而较高的镍摩尔比显示出一致的去除速率为0.1–0.05 g / L / min。对于所有镍铁组合物，反应的前二十分钟拟合了二阶动力学模型，其中速率常数随摩尔比的增加而降低。在反应的最后四十分钟内，偶氮染料的去除符合零级动力学模型。基于XRD光谱中缺乏明显的峰，发现所有合成的纳米颗粒样品在结构上都是无序的。发现反应后样品具有Fe ₂ O ₃和FeOOH立方峰。