Rizafizah Othaman

Rizafizah Othaman
Universiti Kebangsaan Malaysia | ukm · Department of Chemical Sciences

Doctor of Engineering (Chemical Engineering)

About

87
Publications
44,971
Reads
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844
Citations
Citations since 2016
59 Research Items
755 Citations
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200
Introduction
Current Research Interest: 1. Smart Material and adsorbent of CO2 capture 2. Hydrogel from polysaccharide and oligosaccharide 3. Wastewater and water treatment 4. Membrane Separation
Additional affiliations
July 2006 - present
Universiti Kebangsaan Malaysia
Position
  • Professor (Associate)

Publications

Publications (87)
Article
Full-text available
This study aimed to optimize the removal of Cu(II) ions from an aqueous solution using a Jatropha oil bio-based membrane blended with 0.50 wt% graphene oxide (JPU/GO 0.50 wt%) using a central composite model (CCD) design using response surface methodology. The input factors were the feed concentration (60–140) ppm, pressure (1.5–2.5) bar, and solut...
Article
This study highlights the potential use of cellulose nanocrystals (CNC) from kenaf fiber as a dominant phase for aerogel application. CNCs were modified with methyltrimethoxysilane (MTMS) using the sol-gel method and bound with gamma-irradiated cross-linked gelatin. The properties of the aerogel were studied using Fourier transform infrared (FTIR)...
Article
In this work, the effect of magnesium silicate (MgSiO3) as a filler on poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) membrane was investigated towards the enhancement of adsorption capacity for removal of cationic dye. The preparation and fabrication of membranes were performed through copolymerization and phase inversion techniques. Analysis o...
Article
Kajian ini memfokuskan kepada aplikasi hidrogel berasaskan ekstrak pektin daripada kulit buah naga (Hylocereus polyrhizus) yang digunakan sebagai biobahan pembawa ubat. Sebanyak 5 sampel telah disediakan dengan peratus komposisi pektin yang berbeza (0%, 0.5%, 1.0%, 1.5%, 2.0%). Keputusan menunjukkan hidrogel dengan 1.0% pektin telah mengembang seca...
Article
Full-text available
Dalam kajian ini, serabut mesokarpa buah kelapa sawit (SM) telah ditukar menjadi oligosakarida sebagai produk nilai tambah. Objektif kajian ini adalah untuk menentukan kesan prarawatan dan masa hidrolisis untuk penghasilan oligosakarida dengan menggunakan kompleks enzim komersial Celluclast (1.5 L). Prarawatan dengan larutan 5% (v/v) natrium hidrok...
Article
The modification of solid adsorbents with aminating agents amid severe climate change has been intensively studied. Previous organic carbon dioxide (CO2) sorbent like nanoporous activated carbon develops micropores but can be easily blocked by organic amine molecules during the impregnation process. Therefore, in this study, aminosilanes with diffe...
Article
Agro-industrial waste is a by-product of agriculture-based industries which are often rich in lignocellulosic materials and bioactive compounds. The management of these wastes is poorly regulated by the industries where it is commonly discarded in uncontrolled practices. Such activities have created an adverse effect on ecosystem and the economy as...
Article
Full-text available
This paper reviews the preparation of hydrogel based on cellulose and its derivatives. Cellulose is the most abundant natural organic polymer on earth. To date, the exploitation of cellulose has been studied in various applications. However, cellulose has low solubility in water and most organic solvents. Thus, specific solvent systems such as NaOH...
Article
This work investigates the effectiveness of FS loaded with CaO, MgO, and CeO 2 for CO 2 adsorption. Different techniques such as XRD, ATR-FTIR, Raman, CO 2-TPD, in situ FTIR, FESEM, and TEM were employed. Upon the metal oxides loading, the alteration of textural properties, increases in the weak and moderate basic strength and quantity of basic act...
Article
Epoxidised natural rubber (ENR)/polyvinyl chloride (PVC)/silica (SiO2) membranes at a mass ratio of ENR and PVC 60:40 (%w/w) have been prepared by adding different silica amounts. The morphology, mechanical properties, water absorption capacity and water permeability of the membrane were investigated. The membranes were applied for palm oil mill ef...
Article
Full-text available
More recent attention has been focused on the utilization of Jatropha curcas in the field of water treatment. The potential of Jatropha oil in the synthesis of membrane for water filtration had been explored, its performance compared to the addition of graphene oxide (GO) in the polymer matrix. Jatropha oil was modified in a two-step method to prod...
Article
Full-text available
Development of green sorbents to capture carbon dioxide (CO2) whilst minimising their environmental impacts has gained interest among scientists. Deep eutectic solvent has been proposed as a promising green solvent for CO2 separation. In this study, a solid composite adsorbent based on mesoporous silica-gel (SG200) and deep eutectic solvent (DES) m...
Article
Green nanocomposite adsorbent based on nanoporous silica (NS) and deep eutectic solvent (DES) mixture of choline chloride–urea (ChCl:U) was synthesized as an alternative for carbon dioxide (CO2) adsorption. The nanocomposite adsorbent was prepared by sol–gel technique with the variations of ChCl:U (mole ratio 1:2) content in NS at 5–15% (w/w). Four...
Article
Reduction of iron oxide is one of the most studied topics owing to the importance of iron/steel industry and also has been used as a precursor and active component in a number of important chemical processes. The interaction between iron oxide and other metal additive have gained interest in the past two decades due to the ability on enhancing the...
Article
Full-text available
Cellulose fibres and nanofibres have gained interest because of the high strength and firmness, biodegradability and renewability. The enthusiasm in cellulose and its modification as cellulose-derivative has been exponentially expanding. This paper discuss on cellulose and its derivatives, and methods to produce cellulose fibres and nanofibres. Emp...
Conference Paper
Biodegradable nanocomposite adsorbents based on nanoporous silica (NS) and deep eutectic solvents (DESs) mixture of choline chloride:glycerol (ChCl:Gly) and choline chloride:ethylene glycol (ChCl:EG) were synthesized and the ability to adsorb carbon dioxide (CO2) has been studied. All DESs were prepared in mole ratio 1:2 and 10 w/w% were confined i...
Article
Coconut oil in microemulsion is a better option than conventional practice since it can incorporate bioactive ingredients with a stable control release property, especially for hair care products. This work aims to develop microemulsion systems based on coconut oil with the addition of Tween 20, Tween 40, and Tween 80 as non-ionic surfactants (S),...
Article
Full-text available
Croton is a genus of Euphorbiaceae which consists of approximately 1,300 species and are widely distributed in Asia, Africa and South America. Phytochemical study on the root of Croton hirtus has been conducted. The powder of the root of C. hirtus was extracted using the methanol solvent at room temperature for 24 hours and repeated three times. Th...
Article
Epoxidized natural rubber/polyvinyl chloride/microcrystalline cellulose (ENR/PVC/MCC) composite membranes were prepared and used to treat palm oil mill effluent (POME). The loadings of MCC were varied at 0, 5, 10 and 15 w/w%. The increment of MCC loads has intensified the hydroxyl peak of the membranes in FTIR spectrum, indicating the increase in m...
Preprint
Increase demand for palm oil production has indirectly increased waste and pollution. Empty fruit bunch (EFB), which is the major solid waste from this industry, has the potential to be further treated into valuable product. In this study, cellulose will be extracted from EFB through alkali treatment and acid hydrolysis treatment with a different a...
Article
Poly(ethylene glycol)-polydimethylsiloxane (PEG-PDMS) crosslinked copolymers with mol ratios PEG:PDMS:Glycerol of 5:3:2, 6:2:2 and 7:1:2 have been prepared and characterized. The synthesis of the copolymers was carried out by the reaction between hydroxyl groups of PEG, PDMS and glycerol with isocyanate groups of 1,6-hexamethyelene diisocyanate (HM...
Article
The use of biodegradable material in membrane technology will be a great solution in reducing non-biodegradable waste in the landfill. Membranes can often be useful as the recycle stream can usually be much cleaner than with other techniques. This article describes the preparation of poly(l-lactic acid)-poly(ethylene glycol) (PLLA-PEG) free standin...
Article
Full-text available
Islam is a religion that emphasizes human health including the human digestive system. The human stool (stool) discussed in this study is a human waste which is one of the way to look at human health. The objectives of this research were to study the physiochemical and characteristics of stool and its usefulness from the perspective of science whil...
Article
Full-text available
Iota carrageenan purification was done by dissolving iota carrageenan powder in water. The purified iota carrageenan powder was analyzed by using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy and X-Ray Diffraction (XRD) analyses. The powder was used to form a purified iota carrageenan film based solid polymer elect...
Article
The root of Croton hirtus was collected at Tanjung Sepat, Banting for study of its chemical compounds. This sample was dried before being ground and extracted using the methanol solvent at room temperature for three days yielding 18.25 gram of crude extract. The crude extracts obtained were analysed using thin layer chromatography (TLC) then fracti...
Article
The progress of Palm Oil Mill Effluent (POME) treatment in meeting with the regulation and standard stipulated by the Environmental Authority always been a major issue in Palm oil industries. To occupy the palm oil world market demand, palm oil industry needs to produce more than the market demand to supply necessity. Currently, South East Asia cou...
Article
This study was carry out to investigate the effect of 3% rhodium on the reduction behaviour of iron oxide by (10%, v/v) carbon monoxide in nitrogen as a reductant. The Rh/Fe2O3 samples were prepared by impregnation method and the reduction behavior of Rh/Fe2O3 and pure Fe2O3 were investigated by using temperature programmed reduction (TPR). The pre...
Article
Full-text available
Kimia merupakan salah satu cabang ilmu sains yang telah lama dipelopori oleh ilmuwan Islam. Walau bagaimanapun, sekularisme telah menjadikan sains terpinggir dari Islam, apatah lagi merapatkan hubungan di antara manusia dan Pencipta. Seminar Sains Tauhidik telah diadakan untuk menghebahkan pengetahuan dan penemuan oleh penyelidik dari latar belakan...
Article
Full-text available
Industrial training is a compulsory subject that has to be taken by all chemistry students in the School of Chemical Sciences and Food Technology, Faculty of Science & Technology, Universiti Kebangsaan Malaysia. The objective of the study is to identify the marketability of UKM Chemistry students from three different programmes based on the percept...
Conference Paper
The effects of silica content in preparing silica-filled epoxidized natural rubber/polyvinyl chloride (ENR/PVC) beads were investigated. ENR/PVC matrix blend used was of composition 60% (ENR50) and 40% (PVC) by weight. The matrix blend was then dissolved in tetrahydrofuran (THF) by sol-gel technique prior to addition of silica fume as filler at var...
Article
The reduction of pure WO3 and Ce/WO3 has been studied by using temperature programmed reduction (TPR), X-ray diffraction (XRD), and FESEM analysis. The reduction behavior were examined by non-isothermal reduction up to 900 oC then continued with isothermal reduction at 900 oC for 45 min under (40% v/v) carbon monoxide in nitrogen (CO in N2) atmosph...
Article
The reduction behavior of silver doped molybdenum trioxide (Ag/MoO3) and undoped MoO3 by using carbon monoxide, CO were investigated by using temperature programmed reduction (TPR). The reduced phases were characterized by X-ray diffraction (XRD). In the carbon monoxide atmosphere, the XRD results indicated that the reduction of Ag/MoO3 and undoped...
Article
Full-text available
Oil palm empty fruit bunch (OPEFB) is one of the lignocellulosic materials which very well known as an abundant waste at oil mills and need to be utilized. The nanocrystalline cellulose (NCC) was extracted from OPEFB fiber through several of chemical treatment and hydrolyzed with sulphuric acid (H2SO4). NCC acts as support to modify with aminosilan...
Article
Full-text available
The interest in Oil Palm Empty Fruit Bunch (OPEFB) as a promising feedstock for bioconversion into value added products is growing fast, thus a thorough analysis of its component becomes necessary. In this study, the biomass chemical composition and physical feature of OPEFB was analysed to explore and understand the potential of OPEFB as bioconver...
Article
Full-text available
Composite membrane from Epoxidized Natural Rubber/ Polyvinyl Chloride/ Rice Husk (ENR/PVC/RH) was prepared via phase inversion method. The porous membrane was developed that can be used for water permeation application. The effects of addition of RH on thermal stability, mechanical properties pores development, morphology, water absorption, and wat...
Article
Each natural occurrence is a blessing and gives benefit to human being such as menstruation in women. Menstruation is a unique and planned process, which involves three main phases; the menstrual phase, the follicular phase and the luteal phase. The objectives of this research were to study and relate the benefits of menses from the perspective of...
Article
This study was carried out to evaluate the effect of edible film and polyethylene film (PE) on fried sweet potato (Ipomoea batatas) coating. Slices of sweet potato were coated with edible films which were 0.045 g/mL methylcellulose (MC), 0.045 g/mL hydroxypropyl methylcellulose (HPMC) and 0.16 g/mL corn zein (CZ) before being fried at 170-180°C in...
Conference Paper
This paper describes the synthesis and characterization of poly(ethylene glycol) (PEG) and polydimethylsiloxane (PDMS) copolymers. The copolymers were synthesized by reacting hydroxyl group (-OH) of poly(ethylene glycol) (PEG) and polydimetylsiloxane (PDMS) with isocyanate group (R-N=C=O) of 1,6-hexamethylene diisocyanate (HMDI). The reaction was c...
Article
Full-text available
The focus of this research is to prepare epoxidised natural rubber (ENR)/poly(vinylidene fluoride) (PVDF) (ENR/PVDF) membrane using solution casting method and to characterize the ENR/PVDF membrane using universal tensile machine (UTM) and scanning electron microscope (SEM). Composite membrane of ENR/PVDF was prepared by solution casting technique....
Article
Chemical reduction behaviour of 3% chromium doped (Cr–Fe2O3) and undoped iron oxides (Fe2O3) were investigated by using temperature programmed reduction (TPR). The reduced phases were characterized by X-ray diffraction spectroscopy (XRD). The reduction processes were achieved with 10% H2 in nitrogen (%, v/v), 10% and 20% of carbon monoxide (CO) in...
Article
Full-text available
This study was undertaken to investigate the effect of chromium on the reduction behaviour of ferric oxide with carbon monoxide (10 %, v/v) in nitrogen as a reductant. Ferric oxide was impregnated with 3 % chromium to produce chromium-doped ferric oxide (Cr-Fe2O3). The reduction behaviour and the kinetic studies of Cr-Fe2O3 and Fe2O3 have been stud...
Article
Full-text available
Reduction of molybdenum trioxide, MoO3 to molybdenum dioxide, MoO2 by using carbon monoxide, CO has been studied by temperature programmed reduction (TPR) and X-ray diffraction spectroscopy (XRD). The influence of carbon monoxide concentration on the reduction of MoO3 have been investigated by comparing the reduction behaviour of MoO3 to MoO2 with...
Article
Full-text available
The reduction behaviour of molybdenum trioxide, (MoO 3) and nickel (Ni) doped MoO 3 using carbon monoxide (CO) as reductant was investigated by temperature programmed reduction (TPR) and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and transmission electron microscope analysis (TEM). The reduction characteristics of MoO 3...
Article
Full-text available
The reduction behaviour of tungsten oxide has been studied by using temperature programmed reduction (TPR) and X-ray diffraction (XRD). The reduction behavior were examine by nonisothermal reduction up to 900 oC then continued with isothermal reduction at 900 oC for 45 min time under (40% v/v) carbon monoxide in nitrogen (CO in N2) atmosphere. The...
Article
Full-text available
The reduction behaviour of 3% cerium doped (Ce-Fe2O3) and undoped iron oxide (Fe2O3) by hydrogen in nitrogen (10%,v/v) and carbon monoxide in nitrogen (10%,v/v) atmospheres have been investigate by temperature programmed reduction (TPR). The phases formed of partially and completely reduced samples were characterized by X-ray diffraction spectrosco...
Article
Full-text available
The reduction behavior of molybdenum trioxide (MoO3) by carbon monoxide (CO) has been studied using temperature programmed reduction (TPR) and was characterized using X-ray diffraction spectroscopy (XRD). The TPR result shows that the first reduction peak of MoO3 under 20 vol. % CO in nitrogen started at 530 °C and second reduction peaks observed w...
Article
Full-text available
The application of renewable nanomaterials, like nanocrystalline cellulose (NCC), has recently been widely studied by many researchers. NCC has many benefits such as high aspect ratio, biodegradability, and high number of hydroxyl groups which offer great opportunities for modification. In this study, the NCC derived from empty fruit bunches (EFB)...
Article
Full-text available
The reduction of undoped tungsten oxide (WO 3) and doped tungsten oxide has been studied by using temperature programmed reduction (TPR) and characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) and transmission electron microscope (TEM) analysis. Zirconia (Zr) and nickel (Ni) doped tungsten powder were prepared by impregnation met...
Article
Full-text available
This study was undertaken to investigate the effect of noble metals (ruthenium, osmium and silver) on the reduction behaviour of iron oxide by (10%,v/v) carbon monoxide as a reductant. Powder of iron oxide samples doped with noble metal were prepared by impregnation method. The reduction behaviour of samples were characterized by temperature progra...
Conference Paper
In this study epoxidised natural rubber (ENR)/polyvinyl chloride (PVC) matrix was prepared by melt blending. The matrix was swelled in THF and silica as a filler was introduced to the solution to generate pore formation. The ENR/PVC/10 % SiO2 membrane was prepared using a casting knife technique. The membrane was irradiated using 2 MeV electron bea...
Conference Paper
Epoxidised Natural Rubber (ENR) / Poly (Vinylidene Fluoride) (PVDF) (ENR/PVDF) (60:40 wt%) thin film composite membrane was prepared by using solution casting technique. The focuses of this paper are to prepare ENR/PVDF membrane with ratio of ENR to PVDF 60:40 wt%, and to study the effectiveness of treating Palm Oil Mill Effluent (POME) using the m...
Article
Full-text available
Microsized aerogels were prepared from epoxidized natural rubber (ENR)/polyvinyl chloride (PVC) matrix blend using the solvent exchange method and dropping technique with sonication. Some parameters were manipulated in order to observe its effects on resultant aerogels. Parameter studied were ENR/PVC solution viscosity, ratio of ENR/PVC solution to...
Article
Full-text available
In this study, Bacterial cellulose (BC) grafted with Acrylic acid (AA) was prepared using Co60 γ-rays source (30 KGy). Although many samples were prepared, BC: AA with ratio of 1:1 labelled as A1 and 2:1 labelled as A2 gave the most significant results. Hence these particular ratios have been selected and further investigated. AA was proven grafted...
Article
Full-text available
A composite membrane was prepared by mixing epoxidized natural rubber (ENR) and polyvinyl chloride (PVC). An inorganic filler, MgO, was introduced into the polymer matrix by certain percentages to form a mixed matrix membrane (MMM). The resulting membranes were characterized using FTIR, TGA, SEM and gas permeability test. FTIR results showed the in...
Article
Two mixed-matrix membranes (MMM) for gas permeability test were prepared by introducing inorganic fillers (silica (SiO2) and magnesium oxide (MgO)) in the composite blend of epoxidized natural rubber (ENR) and polyvinyl chloride (PVC). Inclusion of SiO2 and MgO particles in the membranes resulted in pores formation as observed through scanning elec...