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All Journal Bulletin of Chemical Reaction Engineering & Catalysis IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Makara Journal of Science
Rizki, Widya Twiny
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Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Environmental Science

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Synthesis of SnO2-Fe3O4 Nanocomposites using Hydrothermal Method Widya Twiny Rizki; Poedji Loekitowati Hariani; Addy Rachmat; Muhammad Said; Nur Hanis Hayati Hairom
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 5, No 3 (2020): October 2020
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v5.i3.88

Abstract

Synthesis of nanocomposite SnO2-Fe3O4 using the hydrothermal method was conducted in this study. The purpose of this study was to determine the best mass ratio in the synthesis of SnO2-Fe3O4. Nanocomposite SnO2-Fe3O4 were made with mass ratio (1:1), (1:2) and (2:1) were characterized using XRD and FTIR. The result of SnO2 characterization using XRD analysis was showed a sharp intensity peak at 2  = 26.5. The result of  Fe3O4 characterization using XRD analysis was showed a sharp intensity peak at 2  = 35.86. The XRD characterization result of SnO2-Fe3O4 (1:2) 2  = 26.74 and 34.08. Based on the XRD characterization, it can be concluded the best mass ratio for SnO2-Fe3O4 was (1:2). Characterization nanocomposite SnO2-Fe3O4 using FTIR showed the absorption band at 590 cm-1 is a characteristic peak of Sn-O and the absorption band at 563 cm-1 corresponds to Fe-O.
Preparation of NiFe2O4 Nanoparticles by Solution Combustion Method as Photocatalyst of Congo red Poedji Loekitowati Hariani; Muhammad Said; Addy Rachmat; Fahma Riyanti; Handayani Citra Pratiwi; Widya Twiny Rizki
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 3 Year 2021 (September 2021)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.3.10848.481-490

Abstract

NiFe2O4 nanoparticles had been successfully synthesized by solution combustion method using urea fuel (organic precursor). The synthesized NiFe2O4 were characterized by X-ray diffraction (XRD), Scanning electron microscopy-Electron Dispersive X-ray Spectroscopy (SEM-EDs), Transmission Electron Microscopy (TEM), Fourier Transform Infra-Red (FTIR), Vibrating Sample Magnetometer (VSM), UV-Vis Diffuse Reflectance Spectroscopy (UV-Vis DRS), and Point of Zero Charge (pHpzc). NiFe2O4 nanoparticles irradiated with visible light were employed to degrade Congo red dye with the following variable: solution pH (3–8), H2O2 concentration (0.5–3 mM), and Congo red concentration (100–600 mg/L). XRD analysis results showed that the NiFe2O4 nanoparticles had a cubic spinel structure. The particle sizes are in the range of 10–40 nm. The magnetic properties of NiFe2O4 nanoparticles determined using VSM showed a magnetization saturation value of 47.32 emu/g. UV-Vis DRS analysis indicated that NiFe2O4 nanoparticles had an optical band gap of 1.97 eV. The success of synthesis was also proven by the EDS analysis results, which showed that the synthesized NiFe2O4 nanoparticles composed of Ni, Fe, and O elements. The removal efficiency of Congo red dye was 96.80% at the following optimum conditions: solution pH of 5.0, H2O2 concentration of 2 mM, Congo red dye concentration of 100 mg/L, and contact time of 60 min. The study of the photodegradation kinetics follows a pseudo-first order reaction with a rate constant value of 0.0853 min−1. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Cr (III)-Doped Bentonite: Synthesis, Characterization and Application for Phenol Removal Purwaningrum, Widia; Vilantina, Vilantina; Rizki, Widya Twiny; Desnelli, Desnelli; Hariani, Poedji Loekitowati; Said, Muhammad
Makara Journal of Science Vol. 25, No. 2
Publisher : UI Scholars Hub

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Abstract

Study of doping process of metal oxide Cr(III) onto bentonite for phenol removal has been done. The purpose of this study was to increase the capacity and effectiveness of bentonite adsorption.The doped bentonite was characterized using XRD, SEM-EDX and FT-IR spectrophotometer analysis. XRD characterization result showed an angle shift (2θ) characteristic at1.609°. The SEM-EDX characterization result showed that bentonite as control have a more gaps than Cr(III)-doped bentonite. Based on EDX result, the Al element decreased from 7.53% to 3.76%, Si from 19.84% to 10.23% and appeared Cr element 2.06%, The FT-IR characterization result showed no significant friction in the spectrum so it can be identified as physical adsorption. The adsorption of phenol was applied at pHpzc, which for bentonite as control was applied at pH 4 and Cr(III)- doped bentonite was applied at pH 8. The phenol adsorption rate fitted to pseudo-second-order and it was found that the equilibrium data was best followed by Freundlich isotherm model, the amount of adsorption rate constant (k) and adsorption capacity (Qe) was 0.0024 g.mg-1min-1 and 16.95 mg/g. The Enthalpy (ΔH) and entropy (ΔS) values decrease with increasing phenol concentration and the positive free energy value was indicated that the proccess was nonspontaneous because there has been an equilibrium state. Based on the adsorption result, it can be concluded that the doping method can produce better bentonite performance to adsorb phenol.
Co-Authors Addy Rachmat Addy Rachmat Desnelli Desnelli Fahma Riyanti Handayani Citra Pratiwi MUHAMMAD SAID Muhammad Said Muhammad Said Nur Hanis Hayati Hairom Poedji Loekitowati Hariani Vilantina, Vilantina Widia Purwaningrum