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Journal : BERKALA SAINSTEK

Extraction and Characterization of Fe2O3 from Red Mud PT. Indonesia Chemical Alumina West Kalimantan Wahyinto, Indi Rizki; Aritonang, Anthoni B.; Zaharah, Titin Anita
BERKALA SAINSTEK Vol 10 No 3 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i3.30252

Abstract

Red Mud is a term used for residues or waste materials from bauxite refining. One of the main compositions of red mud is Fe2O3. This study aims to obtain the optimum extraction of Fe2O3 conditions or hematite by using APDC ligands and knowing the characteristics of Fe2O3 generated. In this study, Fe2O3 extraction begins to determine the optimum pH and ligand concentration. The results of determining the optimum conditions showed pH 1 and ligand concentration of 0.5 M. Fe2O3 characteristics can be resolve through the characterization of Fourier Transformed Infra Red (FTIR), X-ray Diffraction (XRD) and X-ray Fluorescence (XRF). The results of FTIR characterization showed the stretching vibration of Fe-O Fe2O3 phase (570.50 cm-1 and 470.20 cm-1), XRD diffractogram showed the resulting crystal shape is rhombohedralsize is 27,08 nm, while the XRF characterization results showed the mass percent Fe2O3 before extraction is 42.48% and the mass percent Fe2O3 after extraction is 72.443%.
TiO2-rGO Composite for Photocatalytic Decolorization of Methylene Blue Under the Visible Light Illumination Hidayati, Ulfa Farizka; Aritonang, Anthoni B.; Destiarti, Lia
BERKALA SAINSTEK Vol 9 No 4 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i4.27602

Abstract

Titanium dioxide-reduced graphene oxide (TiO2-rGO) was synthesized by hydrothermal method using TiO2 powder and rGO precursor from graphite rod by modified Marcano Method. The obtained TiO2-rGO photocatalyst was characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), and Diffuse reflectance UV (DRUV). Based on XRD diffractogram, it is known that TiO2 has an anatase crystal phase. In the FTIR spectrum, it was observed that there was an absorption peak at the wavenumber of 1630 cm-1 from the vibration (C=C) as an indication that the C atom was incorporated into the TiO2 structure. The incorporation of C atoms into the TiO2 structure to form TiO2-rGO causes the bandgap energy to decrease from 3.29 eV to 3.20 eV. The photocatalytic activity was tested against decolorization of methylene blue solution for 180 minutes under visible light illumination from a 50 watt LED lamp. Every 10 minutes, absorbance was measured using a UV-Vis spectrophotometer at a wavelength of 664 nm. TiO2-rGO photocatalyst has better photocatalytic activity with %D of 96.39% under UV light and 84.32% under visible light illumination, while TiO2 is only able to degrade 93.87% and 36.55%, respectively.
Essential Oils Activity of Legundi Leaf (Vitex trifolia L.) as A Repellent for Rice Weevil (Sitophilus oryzae) Jayuska, Afghani; Warsidah, Warsidah; Asikin, Nurul; Widiyantoro, Ari; Aritonang, Anthoni B.
BERKALA SAINSTEK Vol 10 No 1 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i1.31011

Abstract

Legundi (Vitex trifolia L.) is a plant that contains essential oils. Legundi leaf essential oil has the potential as a more environmentally friendly rice lice repellent. The process of extracting essential oils from Legundi leaves uses the steam-water distillation method. The yield obtained from distillation is 0.10% with a bright yellow color, has a distinctive smell of Legundi oil with a specific gravity of 0.9065 gram/cm3. GC-MS search results showed that Legundi leaf essential oil contains 5 main components, namely 2-β-Pinene (16.18 %), trans-caryophyllene (13.75 %), β-Ocimene (11.16 %), Cyclohexanol (10.03%), and Eucalyptol (5.45%). Testing of repellent activity was carried out on rice lice with variations in volatile oil concentrations of 1%, 5%, 10%, and 20%. The results of the repellent test showed that the highest percentage occurred at a concentration of 20% (P4), which was 56.7%, with an application time of 120 hours (L5). Based on this, it can be said that the greater the concentration of the essential oil used, the higher the percentage of rejection of the population, this also indicates that Legundi leaf essential oil has lice repellent activity (Sitophilus oryzae).