Nur Farhana Diyana Mohd Yunos
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Preferred name
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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The hydrothermal synthesis of TiOâ‚‚-GO with enhance photocatalytic activity

2024-12 , Noor Azira Mohd Noor , Muhammad Asri Idris , Murizam Darus , Nur Farhana Diyana Mohd Yunos

A composite material consisting of titanium dioxide and graphene oxide (TiO₂–GO) was synthesized through a hydrothermal reaction. This reaction involved the use of Ti(SO4)2 in an ethanol–water solvent. Different content of GO was studied to find the optimum parameter. The composites were subjected to characterization, encompassing an examination of their composition, structure, and microstructure through techniques such as X-ray diffraction (XRD), Raman spectra, scanning electron microscopy (SEM), and ultraviolet-visible diffuse reflectance spectroscopy. For Raman spectra, the presence of a G-band at approximately 1599 cm-1 and a D-band at 1350 cm-1 in the spectra indicates the presence of graphene oxide (GO). Therefore, the modified Hummer method synthesized graphite to GO. The findings for the XRD spectrum concerning the TiO2–GO composites revealed the presence of finely dispersed anatase TiO₂ particles on the surface of the graphene oxide sheet layer. Diffraction pattern similar to pristine TiO₂, only for TiO2–GO(0.75) and the peak for rutile TiO2 at 2Ɵ values 27.08° for both technique and TiO₂–GO(0.5) for spray technique. Apparently, GO sheets were almost covered by anchored TiO₂ particles, providing the possibility of efficient electronic conducting and electron transportation as in the SEM microstructures. EDS analysis shows the excessive carbon element for TiO₂-GO(0.75) and TiO₂-GO(1). The findings concerning the TiO₂–GO composites revealed the presence of finely dispersed anatase TiO₂ particles on the surface of the graphene oxide sheet layer. Notably, the photocatalytic performance of the TiO₂–GO composite significantly surpassed that of pure TiO₂ in the photodegradation of methyl blue (MB) when exposed to sunlight. The spray technique had a higher photocatalytic degradation percentage which is 82% for TiO₂-GO(0.25) compared to the dropped technique 79% which is TiO₂-GO(0.5). Degradation analysis of methyl blue concluded that the improved photocatalytic activity of TiO₂–GO primarily results from the enhanced efficiency in trapping and transporting electrons, which can be attributed to the presence of graphene oxide (GO).

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Phase reduction and thermodynamic analysis of Ilmenite Ore by carbothermal-iodination using different carbon reductants

2023-12 , N. A. Nasrun , Nur Farhana Diyana Mohd Yunos , Muhammad Asri Idris , Sri Raj Rajeswari Munusamy , N. Takahiro , S. A. Rezan

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.

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Mineralogical characterizations of Langkawi ilmenite ore for carbothermal reduction

2022-01-01 , Mohammed A.I. , Nur Farhana Diyana Mohd Yunos , Muhammad Asri Idris , Zul Azhar Zahid Jamal , Nur Farhana Hayazi , Nomura T.

The mineralogical characterizations of Langkawi’s ilmenite were investigated using XRD, XRF and SEM/EDS for morphological analysis. The minerals mainly consisted the phases of FeTiO3, Fe3O4 and TiO2 and Rietveld refinement indicated that the ore contained 35.85% of TiO2 and 26.52% of Fe3O4. The amount of the elements calculated form the quantitative and XRF analysis are reliable and in acceptable ranges. The morphology of the ore showed that the ore is formed mainly in sub-rounded grains with titanium and iron as main elements. The ore was categorized as a low-grade ore, but it can be upgraded for TiO2 production using carbothermal reduction reactions, where the results of XRD, XRF, SEM showed extractable amount of TiO2 more than 32wt%.

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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.

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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.

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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.]

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Investigation on phase evaluation of ilmenite ore by carbothermal reduction and carboiodination reaction

2023-12 , A. A. Adel , Nur Farhana Diyana Mohd Yunos , Muhammad Asri Idris , L. I. G. Togang

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.

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Mineralogical characterizations of Langkawi Ilmenite ore for carbothermal reduction

2022-01 , A. I. Mohammed , Nur Farhana Diyana Mohd Yunos , Muhammad Asri Idris , Zul Azhar Zahid Jamal , Nur Farhana Hayazi , T. Nomura

The mineralogical characterizations of Langkawi’s ilmenite were investigated using XRD, XRF and SEM/EDS for morphological analysis. The minerals mainly consist of the phases of FeTiO3, Fe3O4 and TiO2 by Rietveld refinement, which indicated that the ore contains 35.85% of TiO2 and 26.52% of Fe3O4. The amount of the elements calculated from the quantitative and XRF analysis are reliable and in acceptable ranges. The morphology of the ore shows that the ore is formed mainly in sub-rounded grains with titanium and iron as the main elements. The ore is categorized as a low-grade ore, but it can be upgraded for TiO2 production using carbothermal reduction reactions, where the results of XRD, XRF, SEM showed an extractable amount of TiO2 more than 32wt%.

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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.

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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.

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