In this study, aerogel beads composed of graphene oxide and chitosan (GOCA beads) were synthesized and then characterized by SEM, TEM, FT-IR, and BET techniques. The prepared adsorbent was used for the removal of 4-nonylphenol (4-NP) from surface water and municipal wastewater effluent. The adsorption behavior of the nanocomposite was investigated using batch experiments by evaluating the effect of the adsorbent dosage, 4-NP concentration, pH, contact time, total dissolved solids (TDS), and temperature. The adsorption efficiency could reach 100% in 10 min at neutral pH with 1.5 mg L−1 of 4-NP concentration and 0.8 g L−1 of the adsorbent. It was found that the Dubinin–Radushkevich isotherm (R2 = 0.9988, and RMSE = 0.17) with the adsorbents’ maximum capacity of 70.97 mg g−1, and the pseudo-second-order (R2 = 0.9992), as well as the intraparticle diffusion (R2 = 0.9988 and 0.6717) kinetic models, are explained 4-NP adsorption perfectly. The adsorption efficiency increased by augmenting TDS up to 1000 mg L−1. Thermodynamic investigations indicated that the adsorption process was spontaneous, endothermic, and reversible. The adsorbent recovery was successfully performed using ethanol up to 5 cycles. The removal efficiencies of 4-NP from surface water and municipal wastewater effluent were 99.2 and 86.3%, respectively. Since the adsorbent is non-poisonous, inexpensive, rapid adsorption, and easy to separate, we conclude that it will be a favorable option for the removal of 4-NP. 100% adsorption efficiency was achieved in 10 min at neutral pH. 4-NP adsorption on GOCSA beads follows Dubinin–Radushkevich isotherm model. The adsorption follows pseudo second order and intraparticle diffusion kinetic models. The adsorption efficiency increased by increasing TDS up to 1000 mg L−1. The adsorbent recovery was successfully performed up to five cycles. 100% adsorption efficiency was achieved in 10 min at neutral pH. 4-NP adsorption on GOCSA beads follows Dubinin–Radushkevich isotherm model. The adsorption follows pseudo second order and intraparticle diffusion kinetic models. The adsorption efficiency increased by increasing TDS up to 1000 mg L−1. The adsorbent recovery was successfully performed up to five cycles.

中文翻译：

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使用三维氧化石墨烯-壳聚糖气凝胶珠去除地表水和城市污水中的 4-壬基苯酚

在这项研究中，合成了由氧化石墨烯和壳聚糖组成的气凝胶珠（GOCA 珠），然后通过 SEM、TEM、FT-IR 和 BET 技术进行表征。制备的吸附剂用于去除地表水和城市废水中的 4-壬基苯酚 (4-NP)。通过评估吸附剂剂量、4-NP 浓度、pH、接触时间、总溶解固体 (TDS) 和温度的影响，使用批量实验研究纳米复合材料的吸附行为。在中性 pH 条件下，1.5 mg L-1 的 4-NP 浓度和 0.8 g L-1 的吸附剂，吸附效率可在 10 分钟内达到 100%。发现 Dubinin-Radushkevich 等温线 (R2 = 0.9988, and RMSE = 0.17) 与吸附剂的最大容量为 70.97 mg g-1, 和伪二级 (R2 = 0.9992), 以及颗粒内扩散 (R2 = 0.9988 和 0.6717) 动力学模型，完美地解释了 4-NP 吸附。通过将 TDS 增加到 1000 mg L-1，吸附效率增加。热力学研究表明吸附过程是自发、吸热和可逆的。使用乙醇最多可成功回收 5 个循环的吸附剂。地表水和城市污水中 4-NP 的去除率分别为 99.2% 和 86.3%。由于该吸附剂无毒、价格低廉、吸附速度快、易分离，我们认为这将是去除4-NP的有利选择。在中性 pH 条件下，10 分钟内达到 100% 的吸附效率。GOCSA 珠子上的 4-NP 吸附遵循 Dubinin-Radushkevich 等温线模型。吸附遵循伪二级和颗粒内扩散动力学模型。通过将 TDS 增加到 1000 mg L-1，吸附效率增加。吸附剂回收成功进行了多达五个循环。在中性 pH 条件下，10 分钟内达到 100% 的吸附效率。GOCSA 珠子上的 4-NP 吸附遵循 Dubinin-Radushkevich 等温线模型。吸附遵循伪二级和颗粒内扩散动力学模型。通过将 TDS 增加到 1000 mg L-1，吸附效率增加。吸附剂回收成功进行了多达五个循环。GOCSA 珠子上的 4-NP 吸附遵循 Dubinin-Radushkevich 等温线模型。吸附遵循伪二级和颗粒内扩散动力学模型。通过将 TDS 增加到 1000 mg L-1，吸附效率增加。吸附剂回收成功进行了多达五个循环。GOCSA 珠子上的 4-NP 吸附遵循 Dubinin-Radushkevich 等温线模型。吸附遵循伪二级和颗粒内扩散动力学模型。通过将 TDS 增加到 1000 mg L-1，吸附效率增加。吸附剂回收成功进行了多达五个循环。