Abstract
This study investigates the application of alternating current (AC) and direct current (DC) anodization techniques on stainless steel 304L (SS304L) in an ethylene glycol and ammonium fluoride (NH4F) electrolyte solution to produce a nano-porous oxide layer. With limited research on AC anodizing of stainless steel, this study focuses on comparing AC and DC anodization in terms of current density versus time response, phase analysis using X-ray diffraction (XRD), and corrosion rate determined by linear polarization. Both AC and DC anodization were performed for 60 minutes at 50 V in an electrolyte solution containing 0.5% NH4F and 3% H2O in ethylene glycol. The results show that AC anodization exhibited higher current density compared to DC anodization. XRD analysis revealed the presence of ferrite (alpha-Fe) and austenite (gamma-Fe) phases in the as-received specimen, while both AC and DC anodized specimens exhibited only the gamma-Fe phase. The corrosion rate of the AC-anodized specimen was measured at 0.00083 mm/year, lower than the corrosion rate of the DC-anodized specimen at 0.00197 mm/year. These findings indicate that AC anodization on stainless steel offers advantages in terms of higher current density, phase transformation, and lower corrosion rate compared to DC anodization. These results highlight the need for further investigation and exploration of AC anodization as a promising technique for enhancing the electrochemical properties of stainless steel.
Key Words
AC anodizing; corrosion rate; DC anodizing; linear polarization; stainless steel 304L
Address
1) Faculty of Mechanical Engineering and Technology, Universiti Malaysia Perlis (UniMAP),
Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia, 2) Frontier Materials Research, Centre of Excellence (FrontMate), Universiti Malaysia Perlis (UniMAP), Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia
Abstract
This study aimed to investigate the effect of physicochemical properties and mix ratios of iron ore (oxide feed): coke (reductant) on the carbothermic reductions of iron ore. Coke size was fixed at <=63 mum respectively. Mix ratios were changed from 100:0 (reference) to 80:20 and 60:40 while the temperature, heating rate and soaking duration in muffle furnace were fixed at 1100 oC, 10 oC/min and 1 hour. Particle size analyzer, XRF, CHNS and XRD analyses were used for determination of raw feed characteristics. The occurrence of phase transformations from various forms of iron oxides to iron during the carbothermal reductions were identified through XRD profiles and supported with weight loss (%). XRF analysis proved that iron ore is of high grade with 93.4% of Fe2O3 content. Other oxides present in minor amounts are 2% Al2O3 and 1.8% SiO2 with negligible amounts of other compounds such as MnO, K2O and CuO. Composite pellet with finer size iron particles (<=63 mum) and higher carbon content of 60:40 exhibited 45.13% weight lost compared to 32.30% and 3.88% respectively for 80:20 and 100:0 ratios. It is evident that reduction reactions can only occur with the presence of coke, the carbon supply. The small weight loss of 3.88% at 100:0 ratio occurs due to the removal of moisture and volatiles and oxidations of iron ore. Higher carbon supply at 60:40 leads into better heat and mass transfer and diffusivity during carbothermic reductions. Overall, finer particle size and higher carbon supply improves reactivity and gas-solid interactions resulting in increased reductions and phase transformations.
Key Words
carbothermic reductions; diffusivity; physicochemical properties; reactivity; reductant
Address
S.R.R. Munusamy: 1) Faculty of Chemical Engineering & Technology (FKTK), Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia, 2) Frontier Materials Research, Centre of Excellence (FrontMate), Universiti Malaysia Perlis (UniMAP), Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia, 3) SIG Metal Processing and Metallurgy, Faculty of Chemical Engineering & Technology (FKTK), Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia
S. Manogaran, F. Abdullah, N.A.M. Ya'akob and K. Narayanan: Faculty of Chemical Engineering & Technology (FKTK), Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia
Abstract
Fly ash, plastic waste, and clay are mineral materials and residues commonly found in Malaysia. In this study, these materials were fully utilized as raw materials for synthesizing carbon nanotubes (CNTs). Recycled polypropylene, previously used as a food container, served as a carbon source. Fly ash and clay were explored as potential substrates for CNTs growth. The recycled polypropylene was thermally decomposed at 900 oC in an inert environment for 90 minutes. Carbon atoms released during this process were deposited on fly ash and clay substrates, which had been immersed in a ferrocene solution to provide a metal catalyst for CNTs growth. The deposited products were characterized using a Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD). Morphological analysis revealed that both fly ash and clay were coated with fiber-like structures, confirmed to be CNTs based on a diffraction peak around 26o from the XRD pattern. In conclusion, clay and fly ash demonstrate the potential to be utilized as substrates for CNTs formation.
Address
Nur A. Atikah Kamaruddin and Siti A. Hussin: Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis, Taman Muhibbah, 02600 Arau, Perlis, Malaysia
Norzilah A. Halif: 1) Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis, Taman Muhibbah, 02600 Arau, Perlis, Malaysia, 2) Centre of Excellence for Frontier Materials Research, Universiti Malaysia Perlis, Jalan Kangar Alor Setar, Kampung Seriab, 01000 Kangar, Perlis, Malaysia
Mohd. N. Mazlee: 1) Centre of Excellence for Frontier Materials Research, Universiti Malaysia Perlis, Jalan Kangar Alor Setar, Kampung Seriab, 01000 Kangar, Perlis, Malaysia, 2) Faculty of Mechanical Engineering Technology, Universiti Malaysia Perlis, Pauh Putra, 02600 Arau, Perlis, Malaysia
Abstract
D3 tools steel and 440C stainless steel (SS) are normally being employed for application such as knife blade and cutting tools. These steels are iron alloys which have high carbon and high chromium content. In this study, lab work focused on the microstructural and corrosion behavior of D3 tools steel and 440C SS after went through heat treatment processes. Heat treatments for both steels were started with normalizing at 1020 oC, continue with hardening at 1000 oC followed by oil quenching. Cryogenic treatment was carried out in liquid nitrogen for 24 hours. The addition of cryogenic heat treatment is believed to increase the hardness and corrosion resistance for steels. Both samples were then tempered at two different tempering temperatures, 160 oC and 426 oC. For corrosion test, the samples were immersed in NaCl solution for 30 days to study the corrosion behavior of D3 tool steel and 440C SS after heat treatment. The mechanical properties of these steels have been investigated using Rockwell hardness machine before heat treatment, after heat treatment (before corrosion) and after corrosion test. Microstructure observation of samples was carried out by scanning electron microscopy. The corrosion rate of these steels was calculated after the corrosion test completed. From the results, the highest hardness is observed for D3 tool steel which tempered at 160 oC (54.1 HRC). In terms of microstructural analysis, primary carbide and pearlite in the as-received samples transform to tempered martensite and cementite after heat treatment process. From this research, for corrosion test, heat treated 440C SS sample tempered with 426 oC possessed the excellent corrosion resistance with corrosion rate 0.2808 mm/year.
Address
Nur Maizatul Shima Adzali: 1) Frontier Materials Research, Centre of Excellence (FrontMate), Universiti Malaysia Perlis (UniMAP), Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia, 2) Department of Materials, Faculty of Chemical Engineering & Technology, University Malaysia Perlis, Kompleks Pusat Pengajian Jejawi 3, Kawasan Perindustrian Jejawi, 02600, Arau, Perlis, Malaysia
Nurul Abidah Mohamad Khapeli: Department of Materials, Faculty of Chemical Engineering & Technology, University Malaysia Perlis, Kompleks Pusat Pengajian Jejawi 3, Kawasan Perindustrian Jejawi, 02600, Arau, Perlis, Malaysia
Alina Rahayu Mohamed: Department of Chemistry, Faculty of Chemical Engineering & Technology, University Malaysia Perlis, Kampus Uniciti Alam, 02100, Padang Besar, Perlis, Malaysia
Abstract
Aluminum alloy is a material that is frequently used in the aerospace and transportation industries due to its high mechanical and corrosion resistance qualities. Unfortunately, aluminum alloys are prone to corrosion, limiting their application in some harsh situations such as when submerged in aqueous environments. The purpose of this study is to investigate how anodizing can increase the corrosion resistance of 6061 Aluminum alloy. The anodizing process was carried out using two different parameters which are voltage (5V, 10V, 15V) and electrolyte sulfuric acid (H2SO4)
concentration (0.3M, 0.5M) for 1 hour. The anodized samples were performed using several analyses such as X-ray diffraction (XRD) analysis, morphology analysis, and corrosion test. From this study, it is found that the difference in anodizing parameters affects the corrosion resistance of the samples. Sample anodized at 15V, 0.5M gives the best corrosion resistance.
Key Words
6061 aluminum alloy; anodizing; corrosion resistance
Address
Zuraidawani Che Daud and Mohd Nazree Derman: 1) Faculty of Mechanical Engineering and Technology, Universiti Malaysia Perlis (UniMAP), Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia, 2) Frontier Materials Research, Centre of Excellence (FrontMate), Universiti Malaysia Perlis (UniMAP), Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia
Muhammad Faidzi Shukri: Faculty of Mechanical Engineering and Technology, Universiti Malaysia Perlis (UniMAP), Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia
Abstract
Science mapping is a visual representation of the structure and dynamics of scholarly knowledge. Gas adsorption on catalyst supports is a crucial process in many catalytic reactions. The R package "Bibliometrix" and VosViewer software were employed for science mapping analysis. The results show that the upward trend but fluctuates from year to year for both annual scientific production and average article citations per year. Co-occurrence of the keywords were used to identify the primary fields of study and to map the existing state of research. Trending topics reveal some interesting features that support the growth of research in this field and are associated with emerging disciplines or areas of study that have not been extensively explored.
Key Words
catalyst supports; gas adsorption; keywords; science mapping
Address
Mazlee M. N.: 1) Faculty of Mechanical Engineering and Technology, Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia, 2) Frontier Materials Research, Centre of Excellence (FrontMate), 01000 Kangar, Perlis, Malaysia
Zunairah H.: Faculty of Business & Management, Universiti Teknologi MARA, 02600 Arau, Perlis, Malaysia
Abstract
Polylactic acid or polylactide (PLA) is a biodegradable thermoplastic that can be produced from renewable material to create various components for industrial purposes. In 3D printing technology, PLA is used due to its good mechanical, electrical, printing properties, environmentally friendly and non-toxic properties. However, the physical properties and excellent electrical insulation properties of PLA have limited its application. In this study, with the carbon black (CB) as filler added into PLA, the lattice spacing and morphology were investigated by using X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The physical properties of PLA-carbon composite were evaluated by using tensile test, shore D hardness test and density and voids measurement. Impedance test was conducted to investigate the electrical properties of PLA-Carbon composites. The results demonstrate that the inclusion of carbon black as filler enhances the physical properties of the PLA-carbon composites, including tensile properties, hardness, and density. The addition of carbon black also leads to improved electrical conductivity of the composites. Better enhancement toward the electrical properties of PLA-carbon composites is observed with 1wt% of carbon black in N774 grade. The N550 grade with 2wt% of carbon black shows better improvement in the physical properties of PLA-carbon composites, achieving 10.686 MPa in tensile testing, 43.330 in shore D hardness test, and a density of 1.200 g/cm3 in density measurement. The findings suggest that PLA-carbon composites have the potential for enhanced performance in various industrial applications, particularly in sectors requiring improved physical and electrical properties.
Key Words
3D-printing; carbon black; electrical properties; physical properties; PLA
Address
Kang Z. Khor and Thangarajan Mathanesh: Faculty of Chemical Engineering and Technology, Universiti Malaysia Perlis (UniMAP), 02600 Arau, Perlis, Malaysia
Cheow K. Yeoh and Pei L. Teh: 1) Faculty of Chemical Engineering and Technology, Universiti Malaysia Perlis (UniMAP), 02600 Arau, Perlis, Malaysia, 2) Frontier Materials Research, Centre of Excellence (FrontMate), Universiti Malaysia Perlis (UniMAP), 02600 Arau, Perlis, Malaysia
Wee C. Wong: Eco Power Synergy Sdn Bhd, Bandar Puchong Jaya, 47100 Puchong, Selangor, Malaysia
Abstract
Waste tire management and recycling have grown to be significant issues because they bring up a global environmental concern. Thus, turning recycled waste tires into useful products may help tackle the environmental issue. This research aims to study and compare the effect of recycled carbon black (rCB) and commercial carbon black (CB) at certain 15 vol. % of filler loading on the mechanical, thermal, morphology and electrical properties of epoxy/CB composites. For this project, epoxy resin, diethyltoluenediamine (DETDA), recovered carbon black (rCB) and commercial carbon black (CB) graded N330, N550, N660 and N774 were mixed and compared accordingly to the formulation determined. The CB content was dispersed in the epoxy matrix using the mechanical mixing technique. The distribution and dispersion of CB in the epoxy matrix affect the characteristics of the conductive composites. rCB content at 15 vol% was selected at fixed content for comparison purposes due to the optimum value in electrical conductivity results. The flexural strength results followed the sequence of rCB>N774>N660>N550>N330. As for electrical conductivity results, epoxy/N330 exhibited the highest conductivity value, while the others achieved a magnitude of X10-3 due to the highest external surface area of N330. In terms of thermal stability, epoxy/N330 and epoxy/N774 were slightly more stable than epoxy/rCB.
Key Words
conductive materials; epoxy; recovered carbon black
Address
Huai M. Ooi, Xue Y. Lim, Kai K. Yeoh and Nor A. Abdul Rahim: Faculty of Chemical Engineering & Technology, Kompleks Pusat Pengajian Jejawi 2, Universiti Malaysia Perlis, Taman Muhibbah, 02600 Arau, Perlis, Malaysia
Pei L. Teh and Cheow K. Yeoh: 1) Faculty of Chemical Engineering & Technology, Kompleks Pusat Pengajian Jejawi 2, Universiti Malaysia Perlis, Taman Muhibbah, 02600 Arau, Perlis, Malaysia, 2) Frontier Materials Research, Centre of Excellence (FrontMate), Universiti Malaysia Perlis (UniMAP), Perlis, Malaysia
Wee C. Wong and Chong H. Yew: Ecopower Synergy Sdn. Bhd., 1A, Jalan Kenari 9, Bandar Puchong Jaya, 47100 Puchong, Selangor
Chun H. Voon: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Lot 106, 108 & 110, Blok A, Taman Pertiwi Indah, Jalan Kangar-Alor Setar, Seriab, 01000 Kangar, Perlis, Malaysia
Abstract
Quantitative analysis of the Zingiber Officinale sample using subcritical water extraction (SWE) was developed employing High-Performance Liquid Chromatography (HPLC) to bolster the advancement of this innovative green extraction process. This research focuses on three principal ginger bioactive compounds: 6-gingerol, 6-shagoal, and 10-gingerol. Various stages were undertaken to establish the quantitative analysis method, encompassing the optimisation of HPLC operating conditions and the formulation of standard calibration curves, yielding individual compound equations. A robust correlation within the calibration curve was achieved, exhibiting an r2 value of 0.9814 and an RSD of 5.00%. A simultaneous, swift, and dependable method was established with an injection time of 20 minutes and an 8-minute delay between injections, in contrast to the previous HPLC analysis requiring a 45-minute injection time for detecting and quantifying all components. Notably, no post-treatment was applied after the SWE process. This advancement allows for potential future online measurement of Zingiber Officinale bioactive compounds extracted using subcritical water extraction through this technology.
Key Words
10-Gingerol; 6-Gingerol; 6-Shagoal; HPLC; zingiber officinale
Address
Mohd S. Md Sarip: 1) Faculty of Chemical Engineering and Technology, Kompleks Pusat Pengajian Jejawi 3, Universiti Malaysia Perlis (UniMAP), 02600 Arau, Perlis, Malaysia, 2) Frontier Materials Research, Centre of Excellence (FrontMate), Universiti Malaysia Perlis (UniMAP), Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia
Nik M.A. Nik Daud, Mohd A. Mohd Zainudin, Lokman H. Ibrahim and Adilah Anuar: Faculty of Chemical Engineering and Technology, Kompleks Pusat Pengajian Jejawi 3, Universiti Malaysia Perlis (UniMAP), 02600 Arau, Perlis, Malaysia
Syahrul A. Saidi: Faculty of Electrical Engineering & Technology, UniCITI Alam Campus, Universiti Malaysia Perlis (UniMAP), 02100 Sungai Chuchuh, Padang Besar, Perlis, Malaysia
Zuhaili Idham: Department of Deputy Vice-Chancellor (Research and Innovation), Universiti Teknologi Malaysia, 81310 UTM, Skudai, Johor, Malaysia
Abstract
The asymmetric polylactic acid (PLA) membrane was prepared via phase inversion method using non-solvent induced separation (NIPS) technique. This study aims to synthesized as well as to characterize the PLA membrane and evaluating the membrane performance on water flux and permeability. In addition, this research also studied the removal performance of methylene blue dye. The polymer solution has been prepared using 12 wt.% of PLA and dissolved in 88 wt.% of Dimethylacetamide (DMAc) as a solvent. Then, the cast film was immersed in different ratio of coagulant bath medium (distilled water: methanol: ethanol) ranging from 100:0:0, 75:25:0, 75:0:25 and 75:12.5:12.5, respectively). Several characterizations were performed which include, membrane contact angle and membrane porosity. Performance PLA membranes were determined in terms of water flux and permeability at 1 bar transmembrane pressure using dead-end permeation cell. Finally, methylene blue (MB) removal efficiency was tested at the same transmembrane pressure. The findings revealed that the increase of alcohol concentration in coagulant bath resulted in higher porosity and lower contact angle. In short, MB dye rejection efficiency is also closely related to the amount of alcohol ratio used in coagulant baths. Increases in concentration of methanol and ethanol in coagulant bath medium increases the membrane porosity thus increased in efficiency of methylene blue rejection.
Address
Amira M. Nasib, Siti Kartini E. Ab. Rahim, Hoo Peng Yong and Ng Qi Hwa: 1) Faculty of Chemical Engineering & Technology, Universiti Malaysia Perlis, Malaysia, Kompleks Pusat Pengajian Jejawi 3, Kawasan Perindustrian Jejawi, 02600, Arau, Perlis Malaysia, 2) Frontier Materials Research, Centre of Excellence (FrontMate), Universiti Malaysia Perlis (UniMAP), Kampus Tetap Pauh Putra, 02600 Arau, Perlis, Malaysia
Stephen Simon and Syahmie M. Rasidi: Faculty of Chemical Engineering & Technology, Universiti Malaysia Perlis, Malaysia, Kompleks Pusat Pengajian Jejawi 3, Kawasan Perindustrian Jejawi, 02600, Arau, Perlis Malaysia
Khairiraihanna Johari: Department of Chemical Engineering, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia
