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Umi Fazara Md Ali
Preferred name
Umi Fazara Md Ali
Official Name
Umi Fazara, Md Ali
Alternative Name
Ali, Umi Fazara Md
Md. Ali, Umi Fazara
Umi Fazara, M. A.
Main Affiliation
Scopus Author ID
57195513638
Researcher ID
AAU-4840-2020
Now showing
1 - 10 of 29
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PublicationThe impact of ionic strength and pH on the interaction of Pseudomonas putida to minerals and electrical potential of surfaces( 2022-02-01)
;Zuki F.M. ;Edyvean R.G.J. ;Pourzolfaghar H. ;Gafri H.F.S.Bzour M.I.The impacts of the acidity and ionic strength of the solutions were evaluated on the electrical potential of the surfaces as well as the interaction of Pseudomonas putida to quartz and hematite. Zeta potential analysis was performed using the streaming potential technique. Experimental results were performed by the flow cell method. Finally, the extended Derjaguin–Landau–Verwey– Overbeek (XDLVO) theory has been applied to describe bacterial-mineral attachment in terms of the sum of repulsive acid-base and electrostatic interaction energies, and attractive van der Waals interaction energies. The results indicate that the zeta potential is obviously influenced by the presence of bacteria, electrolyte concentration, and pH regions. At higher ionic strengths, charge effects on the bacterial cell surface increase adherence by suppressing the thickness of the diffuse double layer. At pH 5–6, at all ionic strengths, the bacteria adhered more on the surfaces of the minerals. Hematite coupons represented the greatest adhesion at pH 5–6 and an ionic strength 0.1 M. XDLVO theory for the attachment of P. putida to the minerals also confirmed the experimental outcomes. The information obtained in this study is of fundamental significance for the understanding of the survival and transport of bacteria in water distribution, groundwater, and soil systems. -
PublicationAdvancement in recycling waste tire activated carbon to potential adsorbents( 2022-12-01)
;Hussin F. ;Aroua M.K. ;Khamidun M.H. ;Jusoh N.Ahmad S.F.K.Waste tires have been identified as one of the contributors to environmental problems and the issue of inadequate landfill spaces. The lack of consistent and systematic approaches such as specific regulations/laws or mechanisms of waste management to waste tires, limited application of technology for recycling waste tires and lack of awareness on the impacts of waste tires problem, make waste tires a source of environmental pollution. Various researches have been conducted on recycling waste tires into polymer bends, and materials to harden concretes, fuels and adsorbent. Researchers suggested that pyrolysis is the current trend of recycling waste tire to harvest the saleable pyrolysis oil and the recycled carbon black. Therefore, this review attempts to compile relevant knowledge about the potential of adsorbent derived from waste tires to be applied in the removal of various types of pollutants like heavy metals, organic pollutants, dye and air/gaseous pollutant. Studies were carried out on revealing the properties and the characteristics of activated carbon derived from waste tire as effective adsorbent which influence the application performance at liquid or gas phase. In addition, the challenges in the production of activated carbon derived from waste tire were discussed. -
PublicationGasification char residues management: Assessing the characteristics for adsorption application( 2023-09-01)
;Ahmad M.A.Ken K.Due to the world-wide energy crisis and economic issues, biomass has become a resource of global interest as an alternative to activated carbon (AC) produced using non-renewable feedstock (i.e. coal-based). The production of AC from biomass has been determined to be sustainable owing to the abundance of biomass resources on Earth. Biomass gasification has significantly gained market interest and was predicted to reach a value of USD 126 billion by 2023. A critical concern for the existing commercial gasification plants is the handling of char residues, which represent approximately 10% of the initial feedstock mass and are presently treated as waste. The conversion of these chars into AC that can be used for adsorption applications is a possible alternative. This review article focuses on evaluating the characteristic of the gasification char (GC) that is used for adsorption processes. The current AC production method was briefly reviewed. In addition, recent studies on adsorption using GC were explored and summarised. -
PublicationStudy on characterization of bio-oil derived from sugarcane bagasse (Saccharum barberi) for application as biofuel( 2022-04-01)
;Ahmad S.F.K. ;Isa K.M.Lignocellulosic biomass especially, sugarcane bagasse Saccharum barberi sp., appears to be a more suitable material for partial substitution of transport fuel (diesel) than Saccharum officinarum sp., due to its structural similarity to transport fuel (diesel). Besides that, less research has been implemented on this type of species. Bio-oil can be implemented as biodiesel by processing it further using chemical reactions such as hydrodeoxygenation and cracking with zeolite catalyst. Hence, the purpose of this study is to determine the compatibility of pyrolytic bio-oil produced from Saccharum barberi sp. in comparison with S. officinarum sp. for use as transport fuel (diesel) in automotive applications. This purpose can be accomplished by comparing the oil’s bio-physiochemical properties for both species. The experiment is conducted on a bench-scale on which bio-oil of Saccharum barberi sp. is secured from the catalytic pyrolysis process at a temperature of 500°C and heating rate of 50°C/min with the addition of ZSM-Zeolite catalyst. Thermogravimetric analysis of Saccharum barberi sp. reveals that cellulose is more reactive than lignin, evidenced by the high percentage of weight loss at temperatures ranging from 251°C to 390°C. The high contents of carbon (40.7%) and hydrogen (6.50%), as well as slight traces of sulphur (0.08%) and nitrogen (0.85%), in bio-oil (Saccharum barberi sp.) indicate that it is conceivable to be partially used for replacement in biofuel production. Overall physiochemical properties reveal that Saccharum barberi sp. shows more potential than S. officinarum sp. Gas chromatography–mass spectrometry analysis reveals that bio-oil consists of high amounts of aromatic hydrocarbon (26.2%), phenol (14.8%) and furfural (13.0%) in comparison to S. officinarum sp. -
PublicationApplication of regenerated spent bleaching earth as an adsorbent for the carbon dioxide adsorption by gravimetric sorption system( 2022-04-28)
;Phey M.L.P. ;Abdullah T.A.T. ;Ahmad A.The atmospheric level of carbon dioxide (CO2) is indicated to be alarming which in turn has contributed to the worldwide environmental issue such as global warming. The goal of this project was to study the adsorption of CO2 onto regenerated spent bleaching earth (RSBE). Spent bleaching earth (SBE) can be a good adsorbent but it has the weakness in surface area due to the organic impurities left in the pores after being generated from the edible oil processing. Thus, the regeneration processes of SBE by (a) direct heat treatment, and (b) heat treatment followed by nitric acid treatment were studied to enhance the surface area, thus increasing the CO2 adsorption capacity. The SBE were calcined at four temperatures of 400, 500, 650 and 800 °C in the regeneration process. The surface properties of RSBE were characterized using Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) analysis and Brunauer-Emmett-Teller (BET) surface area analysis. The CO2 adsorption capacity on RSBE produced by heat treatment followed by nitric acid treatment was shown to be more effective than RSBE produced by direct heat treatment. RSBE_500_HNO3 offered highest surface area (192.81 m2/g) and give highest CO2 adsorption capacity of 86.67 mg CO2/g. In comparison to the low pressure condition, the high pressure CO2 adsorption values recorded for both RSBE were significantly better. -
PublicationAdsorption of carbon dioxide (CO2) by activated carbon derived from waste coffee grounds( 2021-05-24)
;Lim H.K.Aroua M.K.Currently, three are several agricultural bio-based materials have been successfully utilized as gas adsorbents. In this study, waste coffee grounds (WCGs) have been selected as a potential precursor of Carbon Dioxide (CO2) adsorbents. The preparation parameters for activated carbon derived from WCGs were optimized using Response Surface Methodology (RSM). The optimized preparation parameters were found to be 1:3.67 impregnation ratio of acid, 533oC of carbonization temperature and 1.13 hours of activation time, which resulted in 23.6 wt% of yield. The physical and chemical characteristics of WCGAC in terms of surface morphology, carbon content, ash content and yield were also investigated. The CO2 breakthrough time using WCGAC were carried out at the temperatures of 30, 40, and 60°C. It was found that WCGAC shows a longer CO2 breakthrough times (5 mins) and a higher adsorption capacity (4.33 mg CO2/g adsorbent) at 30oC. -
PublicationSulfur dioxide removal by calcium-modified fibrous KCC-1 mesoporous silica: kinetics, thermodynamics, isotherm and mass transfer mechanism( 2022-04-01)
;Hanif M.A. ;Tuan Abdullah T.A.Jalil A.A.The removal of sulfur dioxide from industrial flue gas through dry flue gas desulfurization method commonly involves the use of adsorption process with porous sorbent. The efficiency of this process is highly dependent on the adsorption capacity and the adsorption rate of SO2 onto the sorbent materials. The use of KCC-1 mesoporous silica modified with calcium metal additives (Ca/KCC-1) in SO2 adsorption is examined in a fixed bed reactor system. The adsorption capacity of Ca/KCC-1 is found to be critically governed by the reaction temperature and inlet SO2 concentration where low values of both parameters are favorable to achieve the highest adsorption capacity of 3241.94 mg SO2/g sorbent. SO2 molecules are adsorbed on the surface of Ca/KCC-1 by both physisorption and chemisorption processes as assumed by the Avrami kinetic model. Thermodynamic study shows that the process is exothermic and spontaneous in nature, and changes from an ordered stage on the surface of KCC-1 towards an increasingly random stage. The process is well explained by Freundlich isotherm model indicating a slightly heterogeneous process and moderate adsorption capacity. The adsorption stage is limited by film diffusion at the initial stage and by intraparticle diffusion during the transfer of SO2 into the network of pores before adsorption takes place on the active sites. -
PublicationNon-Enzymatic Glucose Sensors Involving Copper: An Electrochemical Perspective( 2023-01-01)
;Aun T.T. ;Salleh N.M.Manan N.S.A.Non-enzymatic glucose sensors based on the use of copper and its oxides have emerged as promising candidates to replace enzymatic glucose sensors owing to their stability, ease of fabrication, and superior sensitivity. This review explains the theories of the mechanism of glucose oxidation on copper transition metal electrodes. It also presents an overview on the development of among the best non-enzymatic copper-based glucose sensors in the past 10 years. A brief description of methods, interesting findings, and important performance parameters are provided to inspire the reader and researcher to create new improvements in sensor design. Finally, several important considerations that pertain to the nano-structuring of the electrode surface is provided. -
PublicationAdsorption of 4-Nitrophenol from wastewater using Sea Mango (Cerbera odollam) based Activated Carbon( 2020-04-30)
;Zufarhana Zulkurnai N.Ru Shien T.The presence of phenols and phenolic compounds in water and wastewater has gained great public attention and it is one of the most frequent pollutants in wastewater. In this study, the adsorption of 4-Nitrophenol from wastewater using activated carbon prepared from the non-edible Sea Mango (Cerbera odollam) fruit was investigated. The Sea Mango Activated Carbon (SMAC) was prepared through a physicochemical activation which consists of H3PO4 impregnation and followed by CO2 gasification. The influences of process variables represented by solution pH value, contact time, initial concentration and adsorbent dosage on removal efficiency of 4-NP onto Sea Mango Raw Material (SMRM) and Sea Mango Activated Carbon (SMAC) were studied. Result showed that the optimum pH for 4-NP removal was at pH 3. The dosage usage required to complete 100 ml of 4-NP on SMRM and SMAC was 1.0 g. Batch studies were performed to evaluate the adsorption process, and it was found that the Freundlich isotherm effectively fits the experimental data for the adsorbates better than the Langmuir model with the highest adsorption capacity 158.730 mg/g of 4-nitrophenol on SMAC. It was found that 70.49% and 97.98% of 4-NP was adsorbed onto SMRM and SMAC, respectively, at an initial concentration of 20 mg/L. -
PublicationThe Grease Formulation Using Waste Substances from Palm Oil Refinery and Other Industrial Wastes: A Review( 2023-08-01)
;Hairunnaja M.A. ;Aziz M.A.A. ;Bashari N.A.F. ;Arifin M.A. ;Nedumaran N.Many applications use Spent Bleaching Earth (SBE) despite being considered hazardous waste from the palm oil refinery process. Its production increases yearly, similar to waste cooking oil (WCO). The SBE is known as a thickener in grease formulation. The same goes for red gypsum, waste motor oil, stearic acid, and lithium hydroxide monohydrate. They are all considered thickeners but have different durability in protecting base oil in grease. Then, previous studies revealed their performances with side effects detection against the environment and human bodies. Cooking oil is a heat transfer medium for serving foods with higher amounts of unsaturated fatty acids. The number of fatty acids might change after cooking oil consumption and become highly demanded due to the chemical properties of density, viscosity and fatty acids. Nowadays, people lack awareness of the importance of recycling palm oil waste. They intend to dispose of it instead of recycling it for sustainable energy resources. Therefore, this paper will discuss the grease formulation, contaminant available in WCO, its treatment, issues regarding different thickener consumption, treatment against Spent Bleaching Earth (SBE), and propose the safe thickener and additives for future intakes. This study found that adding Fume Silica (F.S.) as a thickener and Molybdenum Disulfide (MoS2) enhanced the grease stability. Further treatment against SBE (remove residue oil) and WCO (metal elements, undesired impurities and water content) is necessary for providing good quality formulated grease.