School of Environmental Science and Engineering, Indian Institute of Technology, Kharagpur, 721302, India.
Department of Civil Engineering, Indian Institute of Technology, Kharagpur, 721302, India.
Int J Biol Macromol. 2017 Nov;104(Pt B):1548-1555. doi: 10.1016/j.ijbiomac.2017.02.042. Epub 2017 Feb 16.
Cadmium is one of the most toxic heavy metals, which has been classified as human carcinogen and tetratogen. In the present study chitosan (CS) beads are modified, in a novel way, using sodium dodecyl sulfate (SDS), a well known anionic surfactant. The concentration of SDS has been judiciously selected to form surfactant bilayers on CS surface. These modified beads are designated as surfactant-modified chitosan (SMCS) beads. The adsorbent has been characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The SMCS beads are used as an adsorbent for Cd ion removal (in the initial concentration range of 10-100mg/L) from aqueous medium. The removal follows pseudo-second order kinetic model. SMCS beads show adsorption capacity three times higher than normal CS beads. Adsorption isotherm data fits well to the Langmuir model. The maximum adsorption capacity obtained is 125mg/g. Removal efficiency reached to almost 100% at SMCS dosage of 0.45g/L for lower concentration (10-30mg/L) of Cd ion in 10h, whereas, for higher concentration (40-100mg/L) the removal was ca. 50%.
镉是毒性最大的重金属之一，已被归类为人类致癌物和致畸物。在本研究中，壳聚糖 (CS) 珠粒被以新颖的方式用十二烷基硫酸钠 (SDS) 进行改性，SDS 是一种众所周知的阴离子表面活性剂。SDS 的浓度经过精心选择，以在 CS 表面形成表面活性剂双层。这些经过修饰的珠粒被指定为表面活性剂修饰的壳聚糖 (SMCS) 珠粒。通过扫描电子显微镜 (SEM)、傅里叶变换红外光谱 (FTIR) 和 X 射线衍射 (XRD) 对吸附剂进行了表征。SMCS 珠粒用作从水介质中去除 Cd 离子的吸附剂（初始浓度范围为 10-100mg/L）。去除遵循伪二级动力学模型。SMCS 珠粒的吸附容量比普通 CS 珠粒高 3 倍。吸附等温线数据很好地符合朗缪尔模型。在 10h 内，SMCS 用量为 0.45g/L 时，较低浓度（10-30mg/L）的 Cd 离子的最大吸附容量为 125mg/g，而较高浓度（40-100mg/L）的去除率约为 50%。
