The objective of the present study is to investigate removal of cationic dye, rhodamine B (RhB), in water environment using a high-performance absorbent based on metal oxide nanomaterials toward green chemistry. The adsorption of sodium dodecyl sulfate (SDS) onto synthesized alpha alumina (α-Al₂O₃) material (M0) at different ionic strengths under low pH was studied to fabricate a new adsorbent as SDS-modified α-Al₂O₃ material (M1). The RhB removal using M1 was much higher than M0 under the same experimental conditions. The optimal conditions for RhB removal using M1 were found to be contact time 30 min, pH 4, and adsorbent dosage 5 mg/mL. The maximum RhB removal using M1 achieved 100%, and adsorption amount reached 52.0 mg/g. Adsorption isotherms of RhB onto M1 were well fitted by the two-step adsorption model. The electrostatic attraction between positive RhB molecules and negatively charged M1 surface controlled the adsorption that was evaluated by the surface charge change with zeta potential and adsorption isotherms. Very high RhB removal of greater than 98% after four regenerations of M1 and the maximum removal for all actual textile wastewater samples demonstrate that SDS-modified nano α-Al₂O₃ is a high-performance and reusable material for RhB removal from wastewater.

中文翻译：

---

基于新型吸附剂的表面活性剂修饰的α-氧化铝纳米粒子对罗丹明B的吸附去除

本研究的目的是研究使用基于金属氧化物纳米材料的高性能吸收剂向水化学环境中的阳离子染料若丹明B（RhB）的去除。研究了十二烷基硫酸钠（SDS）在低pH条件下在不同离子强度下对合成的α-氧化铝（α- Al ₂ O ₃）材料（M 0）的吸附，从而制备了一种新型的吸附剂，作为SDS改性的α - Al ₂ O _3。材料（M 1）。在相同的实验条件下，使用M 1去除RhB远远高于M 0。使用M去除RhB的最佳条件发现1为接触时间30分钟，pH为4，吸附剂剂量为5 mg / mL。使用M 1的最大RhB去除率达到100％，吸附量达到52.0 mg / g。两步吸附模型很好地拟合了RhB在M 1上的吸附等温线。正RhB分子与带负电的M 1表面之间的静电引力控制了吸附，该吸附由表面电荷随Zeta电位的变化和吸附等温线评估。在四次M 1再生后，RhB的去除率非常高，大于98％，并且所有实际纺织品废水样品的去除率最高，这表明SDS改性的纳米α - Al ₂ O ₃ 是用于去除废水中RhB的高性能和可重复使用的材料。