Environmental pollution from textile industries has become a serious problem. So far, adsorption technology is one of the most effective methods for dye removal, due to its simplicity, high efficiency, and low cost. Superparamagnetic nanoparticles hold great promise for this application. In this work, superparamagnetic magnetite nanoparticles (NP-SYN) were synthesized by chemical co-precipitation, and their adsorption performance was compared to commercial magnetite nanoparticles (NP-COM). The nanoparticles (NPs) were characterized by XRD, TEM, magnetometry, FTIR, and porosimetry. The D_XRD for NP-COM and NP-SYN were around 63 and 27 nm, respectively. The magnetization curves show SM values of 82 and 72 emu g⁻¹ for NP-COM and NP-SYN, respectively. Coercive field for the NP-COM was 1.6 × 10^-2 Oe but could not be measured for NP-SYN, characterizing its superparamagnetic behavior. The surface areas for NP-COM and NP-SYN were around 50 and 127 m² g⁻¹, respectively. Meanwhile, indigo carmine (IC) dye adsorption performances on NPs were investigated. Parameters as pH 4.0, 150 min contact time and 20 mg L⁻¹ dye concentration were chosen for further studies. Maximum NP-COM and NP-SYN adsorption capacity was 6.12 and 17.45 mg g⁻¹, respectively. Batch adsorption process obeys pseudo-second-order kinetics and Langmuir, Freundlich and Temkin isotherms onto NPs. The IC dye removal efficiency was 33 % to NP-COM and 87 % to NP-SYN. After IC dye desorption, NPs were recovered and reused 5 times without losing efficiency. Hence, superparamagnetic magnetite nanoparticles were proposed as potential adsorbent at the solid-liquid interfaces.

纺织工业对环境的污染已经成为一个严重的问题。到目前为止，吸附技术由于其简单，高效和低成本而成为最有效的染料去除方法之一。超顺磁性纳米粒子在该应用中具有广阔的前景。在这项工作中，通过化学共沉淀法合成了超顺磁性磁铁矿纳米颗粒（NP-SYN），并将其吸附性能与市售磁铁矿纳米颗粒（NP-COM）进行了比较。纳米粒子（NPs）的特征是X射线衍射，透射电镜，磁力，FTIR和孔隙率法。NP-COM和NP-SYN的D _XRD分别约为63和27 nm。磁化曲线显示SM值为82和72 emug ^-1分别用于NP-COM和NP-SYN。NP-COM的矫顽场为1.6×10 ^-2 Oe，但无法测量NP-SYN，这是其超顺磁特性。NP-COM和NP-SYN的表面积分别约为50和127 m ²  g ^-1。同时，研究了靛蓝胭脂红（IC）染料在NPs上的吸附性能。选择参数pH 4.0、150分钟接触时间和20 mg L ^-1染料浓度进行进一步研究。最大NP-COM和NP-SYN吸附容量为6.12和17.45 mg g ^-1， 分别。批吸附过程遵循伪二级动力学，Langmuir，Freundlich和Temkin等温线吸附在NP上。IC染料的去除效率对NP-COM为33％，对NP-SYN为87％。IC染料解吸后，NP被回收并重复使用5次而不会损失效率。因此，提出了超顺磁性磁铁矿纳米颗粒作为固液界面的潜在吸附剂。