Recently, removal of nickel ions has been gaining a lot of attention because of the negative impact of nickel ions on the environment. The aim of this review paper is to organize the scattered available information on removal of nickel ions from aqueous solutions through the adsorption process. Survey on investigated materials suggests that composite- and polymer-based adsorbents have the most effective capability for nickel adsorption. The composite material class, i.e. CaCO₃-maltose, followed by biopolymer-based material showed the highest Ni(II) adsorption capacity of 769.23 and 500 mg/g, respectively. The importance of treatment parameters (i.e. pH, temperature, contact time, and metal ion concentration) is discussed, together with their effect on the underlying physicochemical phenomena, giving particular attention to the adsorption/desorption mechanism. It was ascertained that adsorption of nickel ions is pH dependent and the optimal pH range for adsorption of Ni(II) ions was in range of 6–8. In general, nickel adsorption is an endothermic and spontaneous process that mainly occurs by forming a monolayer on the adsorbent (experimental data are often fitted by Langmuir isotherms and pseudo-second-order kinetics). Regeneration (i.e. desorption) is also reviewed, suggesting that acidic eluents (e.g. HCl and HNO₃) allow, in most of the cases, an efficacious spent adsorbent recovery. The percentage use of desorption agents followed the order of acids (77%) > chelators (8.5%) > alkalis (8%) > salts (4.5%) > water (2%). Helpful information about adsorption and desorption of nickel ions from aqueous solutions is provided.

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吸附过程从水溶液中去除镍离子的评论

近来，由于镍离子对环境的负面影响，镍离子的去除已引起广泛关注。本文的目的是整理有关通过吸附过程从水溶液中去除镍离子的分散的可用信息。对被调查材料的调查表明，基于复合材料和聚合物的吸附剂具有最有效的镍吸附能力。复合材料类别，即CaCO ₃-麦芽糖，然后是生物聚合物基材料，分别显示出最高的Ni（II）吸附能力，分别为769.23和500 mg / g。讨论了处理参数（即pH值，温度，接触时间和金属离子浓度）的重要性，以及它们对潜在的物理化学现象的影响，尤其要注意吸附/解吸机理。可以确定的是，镍离子的吸附取决于pH值，镍（II）离子的最佳吸附pH范围为6-8。通常，镍吸附是一个吸热和自发过程，主要发生在吸附剂上形成单层（实验数据通常通过Langmuir等温线和拟二级动力学拟合）。还对再生（即解吸）进行了综述，表明酸性洗脱液（例如HCl和HNO₃）在大多数情况下，可以有效回收废吸附剂。解吸剂的使用百分比遵循以下顺序：酸（77％）>螯合剂（8.5％）>碱（8％）>盐（4.5％）>水（2％）。提供了有关镍离子从水溶液中吸附和解吸的有用信息。