Yunan Amza Muhammad, Sunaryono Sunaryono, Ari June Wilyanto Tyas Nenohai, Siti Zulaikah
Pb (II) pollution through water is the cause of several dangerous diseases. Various efforts have been made to reduce Pb (II) pollution, One of them is by using a sorbent. This study focuses on the effect of grain size and alginate concentration of Fe3O4@SiO2-ALG on absorption efficiency. The synthesis of Fe3O4@ SiO2-ALG was carried out by means of coprecipitation, sol-gel and alginate encapsulation methods. Characterization using FTIR, XRD, TEM, VSM and AAS were carried out to determine grain size, particle morphology and distribution, magnetic properties, material functional groups and absorption of Pb (II). FTIR results show that the sample has a functional group of the main components of Fe-O at wave number 417-570 cm-1 and SiO2 at wave number 801 cm-1 (stretching) and 1198 cm-1 (bending). The stretching vibrations of the aliphatic C-H bonds were seen at 2920-2850 cm-1 which appeared due to the use of organic compounds such as alginates. Another vibration was also detected at the wave number 1107 cm-1 which is the stretching vibration of the C-O bond from the pyrasonyl ring. The wave numbers shown at 1649 and 1460 cm-1 are associated with the asymmetric and symmetric stretching vibrations of the carboxylate salt ion which is characteristic of the alginate structure. The XRD characterization results showed no impurity with a particle size of 10-14 nm. These results were confirmed by TEM characterization with a particle size distribution of 11-13 nm. The VSM results show that the sample has superparamagnetic properties. The decrease in coercivity occurs when the SiO2 concentration is added and the concentration of Alginate increases. Saturation magnetization has decreased with the addition of alginate, which indicates a reduced magnetic response. The test results using the AAS instrument show that the Fe3O4@SiO2-ALG sample has the potential to absorb Pb (II) metal. This is evidenced by the increasing concentration of alginate which has an effect on the increase of Pb (II) uptake by the sample. In addition, the percentage of absorption also increases with the length of time the absorption is given. Based on the fitting with the Langmuir adsorption model, the value of RL, 0 < RL <1 is obtained which explains that the type of adsorption isotherm favorable. © 2023 American Institute of Physics Inc.. All rights reserved.
Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Malang, Indonesia; Centre of Advanced Materials for Renewable Energy, Universitas Negeri Malang, Malang, Indonesia
