Yamuna Munusamy
@utar.edu.my
Associate Professor , Department of Petrochemical Engineering
Universiti Tunku Abdul Rahman
RESEARCH, TEACHING, or OTHER INTERESTS
Polymers and Plastics, Renewable Energy, Sustainability and the Environment, Waste Management and Disposal, Surfaces, Coatings and Films
Scopus Publications
Scopus Publications
Irfan Hassan, Sumathi Sethupathi, Mohammad J.K. Bashir, Yamuna Munusamy, and Chong Woon Chan
Elsevier BV
Mathialagan Muniyadi, Yamuna Munusamy, and Hau Hui Xin
Springer Science and Business Media LLC
Yamuna Munusamy and Mohamed Kchaou
Elsevier BV
Faisal Khaled Aldawood, Yamuna Munusamy, Mohamed Kchaou, and Mohammad Alquraish
MDPI AG
Nitrile butadiene rubber (NBR) latex exhibits excellent tensile properties, chemical resistance, and thermal stability in applications such as gloves and safety shoes due to vulcanization. In this research work, attempts have been made to manipulate the vulcanization to produce thin and compact elastomeric NBR coating on myristic acid (MA) phase change material (PCM) to produce shape-stabilized PCM. The proposal for the use of latex-based elastomeric coating for PCM has been rarely considered in the literature due to a lack of understanding of the crosslink of elastomers. Thus, in this research, the effects of sulfur formulation on the coating performance of NBR on the PCM in terms of latent heat and thermal stability were determined. Leakage analysis indicates that the MA pellet coated with 0.5 phr of sulfur-cured NBR layer (MA/NBR-0.5) successfully eliminates the leakage issue. A tensile analysis revealed that a durable PCM coating layer must possess a combination of the following criteria: high tensile strength, ductility, and flexibility. Fourier transform infrared analysis (FTIR) and electron microscopy images showed the formation of thin, compact, and continuous NBR coating when 0.5 phr of sulfur was used. The further increment of sulfur loading between 1.0 and 1.5 phr causes the formation of defects on the coating layers, while non-vulcanized NBR layers seem to be very weak to withstand the phase-change process. The recorded latent heat values of melting and freezing of MA/NBR-0.5 are 142.30 ± 1.38 and 139.47 ± 1.23 J/g, respectively. The latent heat of the shape-stabilized MA/NBR-0.5 PCM is reduced by 32.24% from the pure MA latent heat density. This reduction is significantly lower than the reported latent heat reduction in shape-stabilized PCMs in other works. The thermal cycle test highlights the durability of the coated PCMs by withstanding up to 1000 thermal cycles (2.7 years) with less than 2% changes in latent heat value. Cooling performance test on photovoltaic (PV) module shows that the fabricated shape-stabilized PCM could reduce the temperature of the PV module up to 17 °C and increase the voltage generation by 7.92%. Actual performance analysis of shape-stabilized PCMs on the cooling of the PV module has been rarely reported and could be considered a strength of this work.
Mohammad Syahrin Smail, Zunaida Zakaria, Hakimah Osman, Syarifah Nuraqmar Syed Mahamud, and Yamuna Munusamy
AIP Publishing
Nor Azura Abdul Rahim, Loo Yu Xian, Yamuna Munusamy, Zunaida Zakaria, and Suganti Ramarad
Wiley
Yamuna Munusamy, Sumathi Sethupathi, Hanafi Ismail, and Zunaida Zakaria
CRC Press
Fu Yee Xuen, Kwan Wai Hoe, and Yamuna Munusamy
IOP Publishing
Abstract An innovative thermoplastic composite was produced using quarry dust which is an industrial waste from quarry industries. The quarry dust was added into high-density polyethylene (HDPE) using melt blending technique in an internal mixer at different mixing loading ratios. The quarry dust filled HDPE (QD-HDPE) composites were then characterized in terms of morphological and mechanical properties. Analysis on processing torque to produce QD-HDPE composites was conducted and the results showed that the optimum quarry dust loading in HDPE composites is at 30wt%. The results from mechanical test such as ultimate tensile strength (UTS), E-modulus, elongation at break, and flexural strength justify this. Scanning Electron Microscopy (SEM) analysis shows that quarry dust had a rough surface with sharp edges and it can be successfully added into HDPE matrix as a filler. In conclusion, performance of the HDPE composites is enhanced by the incorporation of quarry dust. This indicates that quarry dust is a potential filler to be used in thermoplastic composite industries in order to reduce the production cost and relax the pollution problems.
Chai Kah Siong, Mathialagan Muniyadi, and Yamuna Munusamy
IOP Publishing
Abstract Nitrile butadiene rubber latex (NBRL) based gasket materials were extensively used in the past due to their excellent oil resistance, good abrasion resistance, and shock absorption as well as good high-temperature stability. Recently, carbon black has been introduced to further improve the oil absorption properties and thermal performance of the gasket materials which increased the total costing and makes the processing difficult due to the agglomeration of carbon black in NBRL. Thus, in this research, waste tire powder (WTP) was introduced to develop high-performance coating materials as an alternative to carbon black in NBRL gasket material. Optimization of new compounding formulation has been carried out by manipulating the WTP loading and hybrid WTP-carbon black filler loading. The filler loading was selected based on the desired surface texture and coating thickness. The experience was also carried out by varying the WTP, Sulphur, and plasticizer loading. The desired surface texture and thickness of coating materials were developed at WTP loading of 80phr and 90phr. Whereas, the optimum Sulphur loading was achieved at 1phr - 2phr, and plasticizer loading of 10phr and 15phr. From the experiments carried out, the optimum loading of WTP was 90phr which gives a fully contained gasket composite. Furthermore, DOP optimum loading is 15phr which gives a smooth surface appearance. Lastly, Sulphur with 1phr gives a more even surface texture as compared to 2phr loading.
K. S. Ong, C.H. Lim, Y. Munusamy, K.C. Choo, G. J. Chai, Patmashini Saii, and S. Naghavi
IOP Publishing
Abstract Electronic devices need to be cooled efficiently. Phase change material (PCM) could be incorporated into a conventional fin heat sink (FHS) for such a purpose. This paper reports experimental results obtained on the thermal performances of four FHSs fabricated with different arrays and numbers of hollow aluminium pin fins with various lengths and diameters. Tests were conducted with and without filling them with PCM. Heat input was kept on for 2 hours and varied from 1W, 5W and 10W. Transient heating surface temperatures were recorded on a data logger and plotted every 5 minutes. The results showed that the PCM-filled FHS resulted in faster cooling rates and lower heating surface temperatures. Long and large diameter pins performed better than small and short pins. Efficient fin heat sinks for electronic cooling are essential in view of the weight and size of the component. Hence the findings of this paper would be beneficial for electronic cooling and useful to the electronic industry for efficient thermal energy management.
Tzyy-Jeng Yong, Yamuna Munusamy, Yit-Thai Ong, Wei-Ming Yeoh, and Mohamed Kchaou
IOP Publishing
Abstract Oily wastewater pollution has always been part of the most serious worldwide environmental disaster. Thus, the treatment of oily wastewater is notably crucial. In this work, nitrile butadiene rubber/graphene oxide (NBR/GO) membranes were fabricated by latex compounding and curing method which is comparatively brand-new technique to produce membranes for wastewater treatment. Therefore, the steps in the production need to be studied to enhance the performance of the membrane. Curing temperature is an important factor in the production of the latex-based membrane. In this paper, the effect of curing temperature in the range of 90 °C – 110 °C on the morphology, tensile properties, permeation flux, and oil rejection rate performance of the membrane was studied. The curing temperature was found to affect the surface morphology and integrity of the membranes which sequentially affects the performance of the membrane in terms of strength, permeation flux, and oil rejection rate. NBR/GO membranes cured at the temperature of 100 °C exhibit the highest flux of 491.84 L/m2.hr with an oil rejection rate of 95.44 %, with the ultimate tensile strength (UTS), elongation break (EB%), and E-Modulus (E-mod) of 34.490 MPa, 1627.11 %, and 1.309 MPa, respectively.
Tan Wuan Chien, Mathialagan Muniyadi, and Yamuna Munusamy
IOP Publishing
Abstract The saturation point of Mimusop elengi seed shell powder (MESSP) and the effect of MESSP addition on the mechanical, thermal, water absorption and morphological properties of polypropylene (PP) composites were studied. Tensile fracture, physio-mechanical properties and thermal behavior of composites were characterized using tensile and impact testing, thermogravimetric analysis, scanning electron micrograph, and differential scanning calorimetry. Processability of composites were feasible up to 20 wt. % MESSP by which agglomeration of MESSP and poor dispersion of MESSP in PP was observed above 20 wt% MESSP loading. Increasing MESSP loading showed tremendous improvement in tensile modulus and impact strength, whereas tensile strength and elongation at break were reduced. Water absorption and thermal decomposition of composites remain comparable with addition of MESSP up to 20 wt. %. Reduction of tensile strength was attributed by weak adhesion between MESSP and PP. However, morphological analysis revealed the presence of physical interaction via PP chain interlocking on MESSP surface.
Yamuna Munusamy, John Wong Lin Onn, Mohammed Alquraish, Mohamed Kchaou, and Sumathi Sethupathi
MDPI AG
Photovoltaic (PV) panels must be equipped with a cooling system to increase their electrical output generation. Despite numerous publications on the fabrication of form-stable phase change material (FSPCM) for thermal energy storage application, studies on the usage of FSPCM for PV cooling are incredibly limited. In this work, the cooling performance of myristic acid FSPCM encapsulated with cross-linked nitrile rubber (NBR) was investigated. A fin heat sink (FHS) was employed to hold the FSPCM. The thermal performance of the FHS embedded with FSPCM (FHS-FSPCM) was preliminarily tested in an indoor setup. Results show that the FHS-FSPCM has a lower temperature distribution curve than the bare FHS, highlighting the increase in cooling capability of fabricated FSPCM. Field-testing of PV panels integrated with an FHS-FSPCM displayed that FSPCM manages to reduce the operating temperature of the panel by 4 to 15 °C and increase power output generation by 38.61%.
Seng Tat Lim, Sumathi Sethupathi, Abdulkareem Ghassan Alsultan, and Yamuna Munusamy
American Chemical Society (ACS)
Suganti Ramarad, Chantara Thevy Ratnam, Yamuna Munusamy, Nor Azura Abdul Rahim, and Mathialagan Muniyadi
Springer Science and Business Media LLC
AbstractWaste tire rubber is commonly recycled by blending with other polymers. However, the mechanical properties of these blends were poor due to lack of adhesion between the matrix and the waste tire rubber. In this research, the use of electron beam irradiation and (3-Aminopropyl)triethoxy silane (APTES) on enhancing the performance of 50 wt% reclaimed tire rubber (RTR) blend with 50 wt% poly(ethylene-co-vinyl acetate) (EVA) was investigated. Preparation of RTR/EVA blends were carried out in the internal mixer. The blends were then exposed to electron beam (EB) irradiation at doses ranging from 50 to 200 kGy. APTES loading was varied between 1 to 10 wt%. The processing, morphological, mechanical, and calorimetric properties of the blends were investigated. The stabilization torque and total mixing energy was higher in compatibilized blends. Mechanical properties of RTR/EVA blends were improved due to efficiency of APTES in further reclaiming the RTR and compatibilizing the blends. APTES improved the dispersion of embedded smaller RTR particles in EVA matrix and crosslinking efficiency of the blends. Calorimetric studies showed increased crystallinity in compatibilized blends which corresponds to improved mechanical properties. However, the ductility of the blend was decreased due to increased interaction between EVA and APTES. Presence of APTES increased the efficiency of electron beam irradiation induced crosslinking which was shown through gel content analysis and Charlesby-Pinner equation.
Tzyy-Jeng Yong, Yamuna Munusamy, Shi-Jie Ding, and Hanafi Ismail
Springer Science and Business Media LLC
Mohammed Alquraish, Yong Tzyy Jeng, Mohamed Kchaou, Yamuna Munusamy, and Khaled Abuhasel
MDPI AG
Latex phase blending and crosslinking method was used in this research work to produce nitrile butadiene rubber-graphene oxide (NBR-GO) membranes. This fabrication technique is new and yields environmentally friendly membranes for oil-water separation. GO loading was varied from 0.5 to 2.0 part per hundred-part rubber (pphr) to study its effect on the performance of NBR-GO membrane. GO was found to alter the surface morphology of the NBR matrix by introducing creases and fold on its surface, which then increases the permeation flux and rejection rate efficiency of the membrane. X-Ray diffraction analysis proves that GO was well dispersed in the membrane due to the non-existence of GO fingerprint diffraction peak at 2θ value of 10–12° in the membrane samples. The membrane filled with 2.0 pphr GO has the capability to permeate 7688.54 Lm−2 h−1 water at operating pressure of 0.3 bar with the corresponding rejection rate of oil recorded at 94.89%. As the GO loading increases from 0.5 to 2.0 pphr, fouling on the membrane surface also increases from Rt value of 45.03% to 87.96%. However, 100% recovery on membrane performance could be achieved by chemical backwashing.
Khaled Abuhasel, Mohamed Kchaou, Mohammed Alquraish, Yamuna Munusamy, and Yong Tzyy Jeng
MDPI AG
Industrial developments in the oil and gas, petrochemical, pharmaceutical and food sector have contributed to the large production of oily wastewater worldwide. Oily wastewater pollution affects drinking water and groundwater resources, endangers aquatic life and human health, causes atmospheric pollution, and affects crop production. Several traditional and conventional methods were widely reported, and the advantages and limitations were discussed. However, with the technology innovation, new trends of coupling between techniques, use of new materials, optimization of the cleaning process, and multiphysical approach present new paths for improvement. Despite these trends of improvement and the encouraging laboratory results of modern and green methods, many challenges remain to be raised, particularly the commercialization and the global aspect of these solutions and the reliability to reduce the system’s maintenance and operational cost. In this review, the well-known oily wastewater cleaning methods and approaches are being highlighted, and the obstacles faced in the practical use of these technologies are discussed. A critical review on the technologies and future direction as the road to commercialization is also presented to persevere water resources for the benefit of mankind and all living things.
Khaled Abuhasel, Yong Tzyy Jeng, Yamuna Munusamy, Mohamed Kchaou, and Mohammed Alquraish
MDPI AG
Nitrile butadiene rubber (NBR) latex/graphene oxide (GO) membranes were fabricated through a latex compounding and curing method which is a relatively new method to produce membranes for wastewater treatment. Hence, the steps in the production of the membrane through this new approach need to be evaluated to optimize the performance of the membrane. In this paper, the effect of sulfur loading in the range of 0.5 to 1.5 parts per hundred rubber (phr) on the morphology, crosslink density, tensile properties, permeation flux and oil rejection rate performance of NBR/GO membranes was studied. The sulfur loading was found to influence the surface morphology and integrity of the membrane which in turn affects the performance of the membrane in terms of strength, water flux and rejection rate of oil. Inaccurate sulfur loading produced a membrane with micro cracks, low surface area for filtration and could not withstand the filtration pressure. In this research work, the membrane with 1.0 phr sulfur provides the highest water flux value and oil rejection rate of 834.1 L/m2·hr and 92.23%, respectively. Surface morphology of 1.0 phr sulfur-loaded membrane revealed the formation of continuous membrane with high structural integrity and with wrinkles and folded structure. Furthermore, micro cracks and a less effective surface area for filtration were observed for membranes with 0.5 and 1.5 phr sulfur loading.
Waseem Ahmad, Sumathi Sethupathi, Yamuna Munusamy, and Ramesh Kanthasamy
MDPI AG
Chicken eggshell (ES) is a waste from the food industry with a high calcium content produced in substantial quantity with very limited recycling. In this study, eco-friendly sorbents from raw ES and calcined ES were tested for sulfur dioxide (SO2) and hydrogen sulfide (H2S) removal. The raw ES was tested for SO2 and H2S adsorption at different particle size, with and without the ES membrane layer. Raw ES was then subjected to calcination at different temperatures (800 °C to 1100 °C) to produce calcium oxide. The effect of relative humidity and reaction temperature of the gases was also tested for raw and calcined ES. Characterization of the raw, calcinated and spent sorbents confirmed that calcined eggshell CES (900 °C) showed the best adsorption capacity for both SO2 (3.53 mg/g) and H2S (2.62 mg/g) gas. Moreover, in the presence of 40% of relative humidity in the inlet gas, the adsorption capacity of SO2 and H2S gases improved greatly to about 11.68 mg/g and 7.96 mg/g respectively. Characterization of the raw and spent sorbents confirmed that chemisorption plays an important role in the adsorption process for both pollutants. The results indicated that CES can be used as an alternative sorbent for SO2 and H2S removal.
Anusha Leemsuthep, Zunaida Zakaria, Varaporn Tanrattanakul, Suganti Ramarad, Mathialagan Muniyadi, Tomasz Jaruga, Yamuna Munusamy, Izabela Wnuk, and Paweł Pietrusiewicz
MDPI AG
This paper explored the effects of ammonium bicarbonate and different ratios of epoxy to polyamide on the formation of porous epoxy micro-beads through a single epoxy droplet. A single drop of a mixture, consisting of epoxy, polyamide, and ammonium bicarbonate, was dropped into heated corn oil at a temperature of 100 °C. An epoxy droplet was formed due to the immiscibility of the epoxy mixture and corn oil. The ammonium bicarbonate within this droplet underwent a decomposition reaction, while the epoxy and polyamide underwent a curing reaction, to form porous epoxy micro-beads. The result showed that the higher ammonium bicarbonate content in the porous, epoxy micro-beads increased the decomposition rate up to 11.52 × 10−3 cm3/s. In addition, a higher total volume of gas was generated when a higher ammonium bicarbonate content was decomposed. This led to the formation of porous epoxy micro-beads with a smaller particle size, lower specific gravity, and better thermal stability. At an epoxy to polyamide ratio of 10:6, many smaller micro-beads, with particle sizes ranging from 201 to 400 μm, were obtained at an ammonium bicarbonate content of 10 phr. Moreover, the porous epoxy micro-beads with open pores were shown to have a low specific gravity of about 0.93 and high thermal stability at a high ammonium bicarbonate content. Based on the findings, it was concluded that porous epoxy micro-beads were successfully produced using a single epoxy droplet in heated corn oil, where their shape and particle size depended on the content of ammonium bicarbonate and the ratio of epoxy to polyamide used.
Yamuna Munusamy and Ong Kok Seng
IOP Publishing
Abstract Main barriers for installation of conventional solar water heating system (SWHS) are requirement of large installation area and heavy weight of the heat storage tank consisting water. A storage tank with minimum capacity of 230 liters are needed for household usage and this tank when empty can weigh up to 100 kg while a filled tank could weigh up to 400 kg. In reality, installation of this conventional system require more space and heavy structural support on the roof, which is not available in most houses. As a solution, a form stable light harvesting phase change material (FSLHPCM) integrated compact system is proposed. This new SWHS consists of glass – topped collector cum storage tank filled with FSLHPCM. This new FSLHPCM is form stable, does not leak and exhibit stable latent heat when tested to 1000 thermal cycles. It is capable to not only store heat but can improve the collector efficiency by harvesting the visible light and converting it to heat. The additional light to heat conversion efficiency was 22%. In the new system a maximum 75 liters’ glass-topped collector tank is sufficient to substitute a 230-liter tank. This will reduce installation, renovation and maintenance costs for the SWHS.
Shin Yiing Kee, John Lin Onn Wong, Yamuna Munusamy, Kok Seng Ong, and Yang Chuan Choong
Elsevier BV
John Lin Onn Wong, Yamuna Munusamy, Gen Qian Yu, Shin Yiing Kee, and Ong Kok Seng
Wiley