No abstract

Synthesis, magnetic, and structural properties and adsorption study of magnetic particles of Fe3O4 have been carried out. Magnetic particles were synthesized from natural iron sand of Kata Beach Pariaman West Sumatera using ball milling method. The structural properties of the samples were determined using X-Ray Diffractometer (XRD) technique. Magnetic properties such as magnetization were measured based on hysteresis loop using vibrating sample magnetometer (VSM). Mass susceptibility of the sample was measured using Pasco magnetic probe. It was found that the mass susceptibility of magnetic particles increased significantly as ball milling time increased. Based on VSM results, the magnetic particle of Fe3O4 has magnetization value of 32.26 emu/g with small coercivity of 174 Oe. Moreover, the results showed that ball milling method has succeeded to obtain magnetic particles. The increase of ball milling time resulted in an increase of magnetic moment of the sample. In this research, the magnetic particle of Fe3O4 was added to a solution of methyline blue performed using shaker method. Atomic Adsorption Spectroscopy (AAS) method was used to study the methylene blue degradation.

Hematite nanoparticles of undoped and manganese doped were synthesized from natural sand of Logas District Kuansing Regency Riau Province by ball milling method. Structural and morphological properties of these compounds were studied using X-Ray Diffractometer (XRD) and Scanning electron microscope (SEM) respectively. Crystalline structure, lattice parameters, morphologies of the synthesized compounds were studied and the results are discussed. X-ray diffraction (XRD) confirmed the presence of a hematite (α-Fe2O3) phase. Average crystallite size based on flections (1 0 4) for undoped and manganese doped magnetic iron oxide particles are 39.2 nm and 38.2 respectively. The intensity of (1 0 4) reflection is stronger for magnetic iron oxide synthesized for 60 hours than that of 2 step (60+60) hours ball milling. This indicates the product grown along (1 0 4) direction. The average crystallite size decreases when magnetic iron oxide is doped with 10% Mn as confirmed by SEM images.

Magnetic properties and morphology of natural sand has been carried out in Logas Village, Kuantan Singingi Regency have been determined. Iron sand samples were processed using iron sand separator (ISS) prior to ball milling for separating between magnetic and non magnetic particles. The product of ISS was milled for 90 hours using ball milling first step method with milling ball size of 1.5 cm. Themagnetic and non-magnetic particles of ball milling products were separated  using Neodymium Iron Boron (NdFeB) magnet. The product of ball milling first step then was milled for another 30 hours with milling ball size of 0.5 cm and 0.7 cm. The susceptibility and mass susceptibility were determined based on magnetic induction of a selenoid measured using Probe Magnetic Pasco PS-2162. The composition of Logas natural sand was measured using x-ray fluorescence spectroscopy (XRF). The morphology of the magnetic particles are determined using scanning electron microscope (SEM). The results showed that the particle size of natural sand for 90 hours + 30 hours milling displays the particle sizes from 100 µm to 800 µm. As for the particle size of the samples synthesized with 90 hours + 30 hours for 0.7 cm milling ball size, the particles are almost evenly distributed, which is about 5 µm to 100 µm. The content of Fe and Ti in the sample has increased while for Si has decreased. Mass susceptibility increases with increasing ball milling time and ball milling size.

Determination of magnetic and structural properties of natural sand from Logas Village, Kuantan Singingi have been carried out using a magnetic Probe Pasco PS-2162 and X-Ray Diffraction methode. Samples were synthesized using multi step ball milling methode for 90 and 90+30 hours. Results show that the magneticsuceptibility increased with increasing of ball milling time, from 90 hours to 90+30 hours. This magnetic suceptibility within the interval (46-80000) x 10-8 m3/kg which is the interval of Ilminite mineral (FeTiO3; Antiferromagnetic). X-Ray Fluorescence result showed that the composition of Fe and Ti increased after milled for 90+30 hours, while other element like Si decreased. The XRD result confirmed that the phase of the sample structure is Hematite (α-Fe2O3). However, some other phases including SiO2 and FeTiO3 are observed in diffraction pattern. This indicates that the sample is not purely hematite.

The pristine cryptomelane (OMS-2) and Fe-OMS-2 (1%, 5%, and 10%) have been successfully synthesized by a one-step sol-gel method and characterized by XRD, SEM, BET surface area and AAS. The incorporation of Fe (III) within the structure of OMS-2 leads to an increase in surface area, pore-volume, and catalytic activity for the degradation of methylene blue (MB) and a decrease in the content of K+ and average of pore diameter. The catalytic test indicated that the catalytic activity of Fe-OMS-2 1% is considerably higher that of pure OMS-2. The highest degradation of MB is 93.5% achieved using Fe-OMS-2 1% after 120 minutes of degradation time, the initial concentration of MB of 20 ppm, the catalyst concentration of 0.125 mg and the H2O2 volume of 15 mL. The enhanced catalytic activities of Fe-OMS-2 compared to pristine OMS-2 for catalytic degradation of MB are associated with an increase in surface area, pore-volume, and smaller particle size. The results from catalytic studies imply that the metal doping is an effective strategy to enhance the catalytic activities of OMS-2 for degradation of MB.

Research has been carried out on magnetic susceptibility and magnetic particle composition of natural sand on the Rokan River, Riau Province as a function of the rotating speed of ball milling tubes. The sample is dried in the sun before separating the magnetic particles from non-magnetic particles using an Iron Sand Separator, this result is called the ISS product. ISS products are milled with different milling tube rotational speeds of 100, 150, and 200 rpm with an iron ball with a diameter of 2.0 cm. The product obtained from ball milling is then separated by magnetic and non-magnetic particles using a Neodymium Iron Boron (NdFeb) magnet, this result is called a ball milling product (BM product). The results of this study indicate that the magnetic susceptibility of the ISS product has a value 1,930.771 × 10 -5 , while the value of the magnetic susceptibility of ball milling products increases with the increase in the rotational speed of the tube,

Structural, morphological properties and the catalytic activity of magnetite (Fe3O4) nanoparticles for degradation of methylene blue have been studied. The magnetite nanoparticles were synthesised from Padang beach sand West Sumatera by 2 steps ball milling method. Structures and morphologies of the synthesized magnetite nanoparticles were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was shown that the particle size of the magnetite nanoparticles can be controlled by milling ball size. The average grain size of magnetite particles milled for milling ball size of 0.7 cm and 1.5 cm was found to be 81.25 nm and 30.75 nm, respectively. Scanning electron microscopy (SEM) images show that the particle size of samples decreases as milling ball size increases and the grains exhibit irregular form. The effect of milling ball size on the degradation efficiency of catalytic reaction exhibited a good ability to degrade methylene blue from aqueous solutions with a maximum methylene blue removal rate of 86.79% for 10 hours reaction time.