Abstract The potentials of avocado pear (Pearsea americana) exocarp for the removal of lead and cadmium ions from solutions were characterized in single metal and binary metal systems. The native Pearsea americana was characterized using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The Pearsea americana exocarp adsorbed 98% of lead at the optimum pH value of 4 and 83% of cadmium at pH 5 in a single system. The optimum contact times for lead and cadmium ions were 30 and 60 minutes, respectively. The biosorption of lead and cadmium ions followed a pseudo second-order kinetic model. The equilibrium measurements were better described by the Langmuir and Freundlich models than the Temkin model. The biosorption processes for lead and cadmium ions onto the Pearsea americana exocarp are spontaneous and exothermic. The binding capacities of lead and cadmium ions were reduced in the presence of interfering ions such as calcium, magnesium and sodium. The study therefore demonstrated that the Pearsea americana exocarp may be used as a biosorbent for the treatment of water contaminated by lead or cadmium.

中文翻译：

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使用鳄梨梨外果皮在单一和二元系统中从水溶液中生物吸附铅和镉：竞争离子的影响

摘要 鳄梨梨 (Pearsea americana) 外果皮去除溶液中铅和镉离子的潜力在单金属和二元金属系统中进行了表征。使用傅里叶变换红外光谱 (FTIR) 和扫描电子显微镜 (SEM) 对原生美洲梨进行了表征。在单个系统中，美洲梨外果皮在最佳 pH 值为 4 时吸附了 98% 的铅，在 pH 值为 5 时吸附了 83% 的镉。铅和镉离子的最佳接触时间分别为 30 和 60 分钟。铅和镉离子的生物吸附遵循伪二级动力学模型。Langmuir 和 Freundlich 模型比 Temkin 模型更好地描述了平衡测量。铅和镉离子在美洲梨外果皮上的生物吸附过程是自发的和放热的。在干扰离子（如钙、镁和钠）的存在下，铅和镉离子的结合能力会降低。因此，该研究表明，美洲梨外果皮可用作生物吸附剂，用于处理受铅或镉污染的水。