Nur Farhana Diyana Mohd Yunos
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Nur Farhana Diyana Mohd Yunos
Official Name
Nur Farhana Diyana, Mohd Yunos
Alternative Name
Yunos, Nur Farhana Mohd
Yunos, Nur Farhana M.
Mohd Yunos, Nur Farhana
Yunos, N. F.
Yunos, N. F.M
Nur Yunos, F.
Yunos, Nur F.
Yunos, N. F.D.M.
Yunos, M.
Yunus, Nur Farhana M.
Main Affiliation
Scopus Author ID
44062005100
Researcher ID
I-2598-2019

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  • Publication
    Phase evolution during carbothermal reduction of langkawi ilmenite ore at different reaction times
    ( 2020-01-01)
    Nur Farhana Diyana Mohd Yunos
    ;
    Chong J.H.
    ;
    Mohamed A.I.
    ;
    Muhammad Asri Idris
    In this research, the carbothermal reduction of Langkawi ilmenite ore, FeTiO3 had been conducted by using coke as carbon reductant. All samples were grinded into size of ≤ 63 µm and pelletized using 2.5 g mixture of ilmenite ore with coke based on C/O molar ratio of 1:3 (carbon to reducible oxygen). The carbothermal reduction was conducted in a horizontal tube furnace using 0.1 L/min of argon gas flow at temperature of 1200°C. The ultimate and proximate analysis of carbon reductant was investigated using carbon, hydrogen, oxygen, nitrogen and sulfur (CHONS) analyzer. The phase evolutions and chemical composition analysis was conducted using X-ray diffraction (XRD) and X-ray fluorescence (XRF) for raw ilmenite and reduced ilmenite with coke, respectively. The reduction time was set with 2, 3 and 4 hours to understand the phase evolutions. It was found that Langkawi ilmenite ore contained mainly higher TiO2 and hematite, Fe2O3 where the phases of FeTiO3 and titanomagnetite, (Fe2TiO4-Fe3O4) were detected using XRD. The phase of FeTiO3 evolved into the production of Fe, FeO, TiC, TiO2 and Fe3C when increased the reduction time from 2 to 4 hours. The amount of Fe2O3 production was decreased from 59.16 to 47.02 wt%, while higher value of TiO2 was obtained, increasing from 25.2 to 29.1 wt% due to the reduction of TiO2 to Ti3O5 as the reduction time increased. TiC content is also detected when the reduction time increased by reducing TiCxOy into TiC.
      7  14
  • Publication
    Near surface studies on the role of graphene oxide in the carbon species activities in it-sofc cathode materials
    ( 2020-01-01)
    Murizam Darus
    ;
    Noor Azira Mohd Noor
    ;
    Muhammad Asri Idris
    ;
    Nur Farhana Diyana Mohd Yunos
    Active roles of carbon species in solid oxide fuel cell (SOFC) cathode was simulated by adding graphene oxide (GO) into Ba0.5Sr0.5Co0.2Fe0.8 (BSCF) materials prepared by sol-gel method. The mixture was heated up to intermediate temperature SOFC range (650 – 850 °C) for a period of 5 hours. A depth-profiling measurement by x-ray photoelectron spectroscopy (XPS) technique was carried out to analyse the carbon species activities at near surface of BSCF cathode. A depth-profiling analysis indicated that the GO bond components are retained under the cathode surface and does not affected the formation of carbonate phases in BSCF cathode.
      4  22
  • Publication
    Structural Characterizations and Phase Transition on the Reducibility of Ilmenite Ore with Different Carbon Reductants by Carbothermal Reduction Under Hydrogen Atmosphere
    ( 2023-12-01)
    Nur Farhana Diyana Mohd Yunos
    ;
    Muhammad Asri Idris
    ;
    Nasrun N.A.
    ;
    Kurniawan A.
    ;
    Nomura T.
    ;
    Rezan S.A.
    This research focused on investigating the properties and phase transition of ilmenite ore with various carbon reductants by performing a carbothermal reduction, followed by a hydrogen reduction (Ar:H2) at 900–1000 Â°C to extract rutile from the ore. To comprehend the impact of the carbon structure and characteristics on the reduction performance and incorporate a thermodynamic assessment during reduction reactions, two distinct carbon reductants: graphite (GI) and renewable carbon from palm char (PI), were selected. The phase transitions and reduced samples were examined using both qualitative and quantitative X-ray diffraction. The results revealed that ilmenite ore transformed into pseudobrookite ferrous (FeTi2O5), titanium trioxide (Ti3O5), rutile (TiO2), and iron (Fe) after carbothermal reduction at 1550 Â°C where brookite (TiO2) and anatase (TiO2) peaks were diminished. As the temperature rose during the secondary reduction by hydrogen, the reduction reaction sequenced as follows: FeTi2O5 → Ti3O5 → Ti2O3 → TiO2 and Fe. Due to the carbon structure and superior characteristics, the reduced PI demonstrated a greater degree of TiO2 reduction (81.8%) than the reduced GI (74.8%) at the highest reduction temperature of 1000 Â°C. In the early and middle stages of the reaction at high temperatures, the carbothermal reduction of ilmenite ore with solid carbon and CO participated and produced rutile, iron, and Ti3O5, whereas, in the latter stages, rutile, iron, and Ti2O3 are mostly formed when reduced by hydrogen. In conclusion, employing palm char with hydrogen atmosphere to extract pure rutile from ilmenite ore might be accomplished by using these proposed methods. Graphical Abstract: [Figure not available: see fulltext.]
      1  23
  • Publication
    Phase transformations of Langkawi ilmenite ore during carbothermal reduction using palm char as renewable reductant
    ( 2022-02-01)
    Mohammed A.I.
    ;
    Nur Farhana Diyana Mohd Yunos
    ;
    Muhammad Asri Idris
    ;
    Nur Hazira Najmi
    ;
    Zul Azhar Zahid Jamal
    ;
    Nomura, Takahiro
    The phase transformations of carbothermal reduction of Langkawi ilmenite ore by palm char were studied in reduction temperatures ranging from 1200 °C, 1300 °C, and 1400 °C using a horizontal tube furnace with inert argon gas. The palm shells as renewable carbon reductant for carbothermal reduction of ilmenite ore were converted into palm char using pyrolysis techniques to improve and increase the surface area and carbon content. The present study aims to reduce oxides in ilmenite ore from our local mining to produce titanium oxides by carbothermal reduction process and recycled agricultural waste from palm shell as renewable reductant. The phase and chemical compositions of ilmenite ore and reduced samples were analyzed by XRD and XRF. It was found that ilmenite ore mainly contained titanomagnetite, hematite, and titanium dioxide phases. After carbothermal reduction, the titanomagnetite phase from ilmenite ore was transformed into titanium dioxide, iron titania, iron, and titanium carbide at the highest reduction temperature (1400 °C) via XRD analysis. The phase transformation revealed the porous structure with wider pore size distribution and high carbon from palm char was able to reduce the oxides in ilmenite ore. According to XRF analysis, the TiO2 amount was increased with the temperature; from 25.7 wt.% at 1200 °C up to 50.8 wt.% with the extent of reduction of TiO2 was 78.56% at 1400 °C. The carbothermal reduction of ilmenite ore using palm char as a renewable reductant was possible and promising in mineral ore extractions.
      6  10
  • Publication
    Phase Reduction and Thermodynamic Analysis of Ilmenite Ore by Carbothermal-Iodination using Different Carbon Reductants
    ( 2023-12-01)
    Nasrun N.A.
    ;
    Nur Farhana Diyana Mohd Yunos
    ;
    Muhammad Asri Idris
    ;
    Sri Raj Rajeswari Munusamy
    ;
    Takahiro N.
    ;
    Rezan S.A.
    The present study is on the combination of carbothermal reduction and iodination reaction (carboiodination) process for the phase reduction of ilmenite ore (FeTiO3). The aim is to understand the phase reduction and thermodynamic reaction analysis of ilmenite ore by a combined method of carbothermal-iodination using different carbon reductants (graphite and palm char). Graphite was used as a standard carbon reductant while palm char as a renewable carbon reductant was prepared via the pyrolysis technique. Ilmenite was mixed with carbon reductants and then first reduced by using a carbothermal reduction process at 1550℃. Then, the reduced samples were further investigated with iodination reaction in different temperature ranges of 900-1000 °C using a vertical tube furnace with mixed argon and iodine gas (0.2 L/min). The proximate and ultimate analyses of carbon reductants were analysed by CHON analyser and their microstructure by using SEM, while XRF and XRD were used for analyzing the chemical compositions and the phase reductions of raw ilmenite ore and reduced samples, respectively. The thermodynamics of possible reactions during carbothermal-iodination reactions were calculated by HSC Chemistry 6.0 software. By comparing graphite and palm char, palm char had an amorphous structure, with porous and high carbon content showing high potential for usage as a reductant in titanium extraction from ilmenite ore. The phases of ilmenite ore were ilmenite, rutile, and anatase transformed into rutile, pseudobrookite, and titanium oxide detected by XRD. Further reduction was performed by palm char where more rutile (TiO2) and titanium oxide (Ti3O5) developed from the iodination reaction at the highest temperature compared to graphite due to better properties and amorphous structure. The rutile and titanium oxide were found as stable phases from the thermodynamic analysis and confirmed with XRD. From the findings, the combination of carbothermal-iodination of ilmenite ore was possible and promising for rutile (TiO2) production in mineral extractions.
      1  28
  • Publication
    Investigation on Phase Evaluation of Ilmenite Ore by Carbothermal Reduction and Carboiodination Reaction
    ( 2023-12-01)
    Adel A.A.
    ;
    Nur Farhana Diyana Mohd Yunos
    ;
    Muhammad Asri Idris
    ;
    Togang L.I.G.
    This article presented the thermochemical calculation and experimental investigation on the phase evaluation of ilmenite ore (FeTiO3) via carbothermal reduction and carboiodination reaction for titanium production using graphite as a reducing agent. The carbothermal reduction and carboiodination reactions were performed in two different furnaces. The carbothermal reduction was evaluated at a temperature of 1550°C with inert argon gas utilizing a horizontal tube furnace. The carboiodination reactions were evaluated in temperatures ranging from 900°C, 950°C, and 1000°C using a vertical tube furnace with mixed iodine gas with argon gas. XRF and XRD were used for analyzing the chemical compositions and the phase evolutions of raw ilmenite ore and the reduced samples, respectively. The findings showed that the Perak ilmenite ore predominantly has a greater concentration of TiO2 (71.27wt%), Fe2O3 (18.85wt%), and some other oxides like aluminum oxide and quartz. In addition, XRD revealed that the ilmenite phase was converted into rutile (TiO2) titanium oxide (Ti3O5, Ti2O3), titanium carbide (TiC), and iron (Fe) phases, after the carbothermal reduction process. However, after the carboiodination reaction, the ilmenite and rutile phases remained at temperatures 900°C, 950°C, and 1000°C. The HSC Chemistry software was used in the determination of the thermochemical calculation and the possible reactions during the reaction which play an important role in shortening the reduction process. The results revealed the carboiodination process is a promising process that can reduce energy consumption and shorten the titanium production processes, and it needs more studies.
      1  18
  • Publication
    The Correlation between Palm Shell Char Properties and the Production of Metallic Iron in EAF Steelmaking Slag Reduction Reaction
    ( 2020-11-24)
    Anis Nadhirah Ismail
    ;
    Nur Farhana Diyana Mohd Yunos
    ;
    Sri Raj Rajeswari Munusamy
    ;
    Muhammad Asri Idris
    Palm shells wastes generated from oil palm processing are in abundance in landfills every year thereby posing environmental problems. Enormous amount of wastes generated by agro-industry has previously studied as carbon source in steelmaking hence providing solution to environmental problems. This paper studied on the conversion of palm shell waste into carbon material via physical and chemical activation method for metallic iron extraction. Physical char was prepared by pyrolyzed in nitrogen atmosphere at 450°C while chemical char was impregnated in phosphoric acid before pyrolyzed. Composite pellets of EAF slag (43.18 %Fe2O3) with physical and chemical char were rapidly heated at temperature 1550°C within 20 minutes under argon flow. All reduced samples were analyzed on the weight loss, degree of reduction, iron recovery and phase analysis using X-ray diffraction (XRD). The results indicated that chemical/slag showed higher weight loss (38.8%) and excellent degree of reduction (29.94%) compared to physical/slag due to higher volatile matter content (9.8%) and larger surface area (562.14m2/g). It was found that the production of metallic iron particles after the reduction process and indicated that chemical char achieved higher iron recovery (15.48%) compared to physical char due to higher total carbon content (60.28%). XRD and Rietveld refinement analysis confirmed that the iron phase was a major component in metallic iron particles for physical/slag and chemical/slag samples. This elucidated that the iron oxides in EAF slag was completely reduced into iron by using palm shell chars as carbon materials. This finding indicates that palm shell chars potentially act as carbon materials in steelmaking applications according to their good characteristics.
      5  15
  • Publication
    Effect of using Palm Char and Coke as a Reductant in Production of Ferrosilicon
    ( 2020-11-24)
    Nur Farhana Diyana Mohd Yunos
    ;
    Muhammad Asri Idris
    ;
    Sri Raj Rajeswari Munusamy
    ;
    Dhilip K. Perumal
    This research focused on the synthesis of ferrosilicon alloy by coke and palm char as a reductant. Raw materials which were iron ore, silica sand, coke and palm char mixed and compacted into pellets. The pellets were reduced at temperature of 1300 C using horizontal tube furnace with nitrogen gas flow. The pellets after reduction process were characterized by X-ray fluorescence (XRF), X- ray diffraction (XRD), Scanning electron microscope equipped with energy dispersive spectra (SEM/EDS). The results from XRD analysis indicated that the formation of FeSi, Fe3Si and SiC phases were appeared at 1300 C for both reductants. The brighter phases were observed in SEM/EDS mapping analysis represents as iron and silicon. The EDX analysis showed the high amount silica developed for coke compared to palm char due to high content of silica and carbon. The results found that palm char as carbon reductant has the potential to produce ferrosilicon and silica carbide in sustainable way.
      7  28