Water is essential for humans, animals, and plants; pollutants, usually derived from anthropogenic activities, can have a serious effect on its quality. Heavy metals are significant pollutants and are often highly toxic to living organisms, even at very low concentrations. Among the numerous removal techniques proposed, adsorption onto suitable adsorbent materials is considered to be one of the most promising. The objective of the current study was to determine the effectiveness of halloysite nanotubes (HNT) functionalized with organic amino or thiol groups as adsorbent materials to decontaminate polluted waters, using the removal of Hg²⁺ ions, one of the most dangerous heavy metals, as the test case. The effects of pH, ionic strength (I), and temperature of the metal ion solution on the adsorption ability and affinity of both materials were evaluated. To this end, adsorption experiments were carried out with no ionic medium and in NaNO₃ and NaCl at I = 0.1 mol L⁻¹, in the pH range 3–5 and in the temperature range 283.15–313.15 K. Kinetic and thermodynamic aspects of adsorption were considered by measuring the metal ion concentrations in aqueous solution. Various equations were used to fit experimental data, and the results obtained were explained on the basis of both the adsorbent’s characterization and the Hg²⁺ speciation under the given experimental conditions. Thiol and amino groups enhanced the adsorption capability of halloysite for Hg²⁺ ions in the pH range 3–5. The pH, the ionic medium, and the ionic strength of aqueous solution all play an important role in the adsorption process. A physical adsorption mechanism enhanced by ion exchange is proposed for both functionalized materials.

水对人类，动物和植物至关重要。通常源自人为活动的污染物可能对其质量产生严重影响。重金属是重要的污染物，即使浓度很低，也常常对生物具有剧毒。在提出的众多去除技术中，吸附到合适的吸附材料上被认为是最有前途的技术之一。本研究的目的是确定有机氨基或硫醇基官能化的埃洛石纳米管（HNT）作为吸附材料对污染水的去污效果，方法是去除最危险的重金属之一Hg ²⁺离子，测试用例。pH值，离子强度的影响（I），并评估了金属离子溶液温度对两种材料的吸附能力和亲和力的影响。为此，在没有离子介质的情况下，在pH  = 3-5和283.15–313.15 K的NaNO ₃和NaCl中，在I = 0.1 mol L ^{-1的条件下}，进行了吸附实验。通过测量水溶液中的金属离子浓度来考虑吸附。使用各种方程式拟合实验数据，并在给定的实验条件下，基于吸附剂的表征和Hg ²⁺形态对获得的结果进行了解释。硫醇和氨基增强了埃洛石对Hg ²⁺的吸附能力pH范围为3-5的离子。水溶液的pH值，离子介质和离子强度在吸附过程中都起着重要作用。对于两种功能化材料，都提出了通过离子交换增强物理吸附的机理。