Study of the variation of catalyst loading in cathode for SPEEK/CSMM membrane in direct methanol fuel cell (DMFC)

Variation of anode catalyst loading for modified sulfonated poly (ether ether ketone) (SPEEK) with charged surface modifying macromolecules (cSMM) membrane was studied, in order to get the higher performance in DMFC. The best optimal anode catalyst loading was 4 mgcm-2 for 30% Pt/Ru based on our previous result for this application. The modified SPEEK/CSMM membrane was characterized to ensure of its better performance in term of water uptake and methanol permeability. In cathode side, the effect of 5% and 10% Pd/C in 2,4 and 6 mgcm-2 of catalyst loading has been investigated with a fuel cell assembly. The preparation method of catalyst ink and membrane electrode assembly (MEA) was based on Dr. Blade method and hot pressing by using catalyzed diffusion media (CDM) method. The air flowrates were varied from 25-1000ml min-1, while 1M methanol concentrations, 1 ml min-1 of methanol flowrate and 60°C operating temperature were kept constant. These parameters were tested on the performance of single cell DMFC with 4 cm2 electrodes.The optimization catalyst loading will enhance the DMFC performance. It was found, the best optimal cathode catalyst loading was 4 mgcm-2 for 10% Pd/C with 4 mgcm-2 for 30% Pt/Ru in anode side for this application

Production of lactic acid from kenaf core hydrolysate by rhizopus oryzae FTCC 5215

Lactic acid (LA) is commercially produced biologically using food-derived raw materials such as potato and corn. It seems to be less economical since they have to compete with the food sources industries. Thus, kenaf (Hibiscus cannabinus) is found to be the best alternative to substitute the raw material for LA production. In this paper, kenaf core were used as the substrate for production of LA by Rhizopus oryzae FTCC 5215. Since kenaf is one type of lignocellulosic material which is naturally resistant to breakdown to its structural sugars, it will inhibit microorganisms to be accessed through. Thus, hydrolysis process is needed as the aid for the liberation glucose. The highest value of lactic acid produced is 15.2 g/L at 25 oC with speed 200 rpm

Leakage current analysis on polymeric and non-polymeric insulating materials using time-frequency distribution

This paper presents the performance of polymeric and non-polymeric insulation material in contaminated condition. The purpose of this study is to determine the accuracy of analysis technique on the performance these types of insulation against its tracking and erosion. Polypropylene and glass are selected as polymeric and non-polymeric material. Tracking and erosion test complying with BS EN 60587-2007 are conducted, then leakage current frequency components is used as a diagnostic tool for their surface condition monitoring and degradation severity. The analyses of leakage current are based on frequency domain and time-frequency representations are conducted. From the results, the surface condition of polymeric insulation material state can be classified accurately by using spectrogram compared to Fast Fourier Transform. It also proved that the performance of tracking and erosion of glass is better than polypropylene material

The awareness of Islamic retirement planning and the practice with Muslims employees in Malaysia / Mohd Shafiz Saharan...[et al.]

This study examines the extent of Malaysians awareness on Islamic retirement planning and the predictors for the dependent variable. This study also delves into the concept of Islamic retirement planning, attitudes on investment, savings behaviour, social security and financial literacy to see the awareness issues surrounding the study of retirement. Studies have shown that Malaysians awareness on retirement planning can be considered low and only 40 percent is ready enough to retire while the rest need to retire with insufficient fund due to consumption and savings behaviour as predicted by the life-cycle theory of savings. As a country with Muslims as the dominant population, there is an urge to address this issue and to see whether or not their income and savings comply to Syariah. Data will be collected using questionnaire survey method on Muslim employees in private sectors in Malaysia. A total of 150 questionnaires will be distributed to obtain the data on the awareness of Islamic retirement planning among Muslims private employees. Data will further be analysed by the use of descriptive analysis, reliability analysis and regression analysis, and will be presented in the forms of frequency graph and table. This study expects to show the significant relationships between the independent variables which are attitudes on investment, savings behaviour, social security and financial literacy towards the awareness on Islamic retirement planning. The result is also expected to show a lower awareness of Islamic retirement planning as literatures found that most Malaysians are lacking in retirement planning. Therefore, it is important to look into extensive information regarding the level of awareness on the Islamic retirement planning so that some persistent efforts can be done in giving pre-retirement awareness program that complies to Syariah

Fabrication of nanocomposite membrane via combined electrospinning and casting technique for direct methanol fuel cell

Emergence of nanotechnology has resulted in the introduction of the electrospinning process in fabricating and characterising the polymer electrolyte membrane from the sulfonated poly (ether ether ketone) (SPEEK) nanocomposite membrane comprised of electrospun Cloisite15A® (e-spun CL) for direct methanol fuel cell (DMFC). Poly (ether ether ketone) polymer is sulfonated up to 63% by sulfuric acid. SPEEK63/e-spun CL nanofibers were fabricated via electrospinning in which SPEEK63 was used as carrier polymer while the SPEEK63/e-spun CL nanocomposite membrane was obtained by the casting method. Characterizations on physical, morphological and thermal properties of SPEEK63/e-spun CL were conducted and compared to the SPEEK membrane fabricated by casting simple mixing 2.5wt.% Cloisite15A® and 5.0wt.% triaminopyrimidine solution (SPEEK63/2.5CL/5.0TAP). Scanning electron microscopy (SEM) showed well electrospun Cloisite15A® with an average diameter nanofiber around 187.4 nm. Moreover, field emission scanning electron microscopy (FESEM) revealed that Cloisite15A® particles at a nanometer range were uniformly distributed and 66% smaller than those in SPEEK63/2.5CL/5.0TAP. Furthermore, x-ray diffraction proved that the dispersion state of Cloisite15A® fell into an intercalated phase. A very small amount of Cloisite15A® (0.05wt.%) in SPEEK63/e-spun CL successfully enhanced the proton conductivity up to 50%, whereas, unfortunately the methanol permeability value was 27 times higher than SPEEK63/2.5CL/5.0TAP. Proton conductivity and methanol permeability of SPEEK63/e-spun CL were 24.49 x 10-3 Scm-1 and 3.74 x 10-7 cms-1, respectively. Even though this study contributed to 95% selectivity lower than SPEEK63/2.5CL/5.0TAP, electrospinning showed a promising technique to further reduce original sized Cloisite15A® particles from mixed size (μm and nm) to nanometer sized. In addition, by fine tuning, the dispersion of Cloisite15A® enhances the SPEEK63/e-spun CL performance in DMFC

The effect of hydroxyapatite nanoparticles on wettability and brine-oil interfacial tension as enhance oil recovery mechanisms

A novel concept of utilizing nanoparticles (NPs) to boost oil recovery and reduce entrapped oil in hydrocarbon reservoirs is being explored. The use of nanofluids (NFs) flooding to change wettability and reduce interfacial tension (IFT) between oil and water has been shown to be highly effective in experiments. Preparation and modification methods influence the performance of NPs. The application of hydroxyapatite NPs (HAP) in EOR has yet to be investigated. HAP was synthesized in this study using the co-precipitation method and in-situ surface functionalization with Sodium Dodecyl Sulphate SDS to visualize it effect on IFT reduction and wettability alteration under different salinity and temperature settings. To confirm the synthesis of HAP, zeta potential (ZP), Fourier transform infrared spectroscopy (FTIR), Particle size analysis (PSA), Transmission electron microscopy (TEM), and Energy dispersive X–ray (EDX) spectra were used respectively. According to the results, HAP was produced, and the particles were finely distributed and stable in aqueous solution. When the pH was altered from 1 to 13, the particles' surface charge rose from -5mV to −27mV, showing long-term stability in EOR processes. At salinity range from 5000 ppm to 30,000 ppm, and under temperature range from 25ᵒC to 80ᵒC, the HAP NFs changed the wettability of sandstone core from oil–wet at 111.7° to water–wet at 9.0°. In addition, at 0.1 wt% HAP concentration, the IFT was lowered to 3 mN/m. As a result, the HAP NF proved very effective in reducing IFT and altering wettability under both low and high salinity environments, and it is thus suggested for EOR operations

Polymer nanocomposites application in drilling fluids: A review

Indubitably, drilling fluid is the most crucial component of drilling operations. With the current exploration of hydrocarbons in deep water horizons, unconventional formations, and anticipated production from the arctic regions, there is a need to improve the properties of existing drilling fluids for harsh conditions. Recently, the synergic combination of polymer and nanoparticle (polymer nanocomposite) has gained prodigious attention for application as a drilling fluid additive due to its sterling and fascinating properties. Herein, the application of polymer nanocomposite (PNC) as an additive in drilling fluids has been reviewed. The survey of the literature shows that PNC significantly improved the rheological, filtration, and shale swelling inhibition properties of drilling fluids. Nonetheless, accurate modelling of its behaviour remains elusive. The mechanism of the improved efficiency of PNC as a drilling fluid additive was elucidated. Finally, the gaps in the research were highlighted, and recommendations for future studies were outlined. Overall, drilling fluids containing PNC exhibited comparably higher efficiency and immense potential to overcome severe wellbore problems encountered with conventional drilling fluids

Effect of salinity on hydroxyapatite nanoparticles flooding in enhanced oil Recovery : A mechanistic study

Fluid-fluid interactions can affect any enhanced oil recovery (EOR) method, including nanofluid (NF) brine-water flooding. Flooding with NFs changes wettability and lowers oil-water interfacial tension (IFT). Preparation and modification affect the nanoparticle (NP) performance. Hydroxyapatite (HAP) NPs in EOR are yet to be properly verified. HAP was synthesized in this study using co-precipitation and in situ surface functionalization with sodium dodecyl sulfate in order to investigate its impact on EOR processes at high temperatures and different salinities. The following techniques were employed, in that sequence, to verify its synthesis: transmission electron microscopy, zeta potential, thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, particle size analysis, and energy-dispersive X-ray spectra. The outcomes showed the production of HAP, with the particles being evenly dispersed and stable in aqueous solution. The particles' surface charge increased from -5 to -27 mV when the pH was changed from 1 to 13. The HAP NFs at 0.1 wt % altered the wettability of sandstone core plugs from oil-wet at 111.7 to water-wet at 9.0 contact angles at salinity ranges of 5000 ppm to 30,000 ppm. Additionally, the IFT was reduced to 3 mN/m HAP with an incremental oil recovery of 17.9% of the initial oil in place. The HAP NF thus demonstrated excellent effectiveness in EOR through IFT reduction, wettability change, and oil displacement in both low and high salinity conditions

Amphipathic anionic surfactant modified hydrophilic polyethylene glycol-nanosilica composite as effective viscosifier and filtration control agent for water-based drilling muds

Highly stabilized and dispersible composites of polyethylene glycol and silica nanoparticle in aqueous drilling mud can provide desirable rheological and filtration properties for drilling jobs. Therefore, high-quality hydrophilic polyethylene glycol-nanosilica composite modified by amphipathic anionic sodium dodecyl sulfate (PEG-SiO2 NC-SDS) to improve the rheological and filtration properties of water-based muds (WBMs) was submitted. Test of zeta potential, functional groups, morphology, elemental composition, and temperature stability together with rheology and filtration tests were undertaken to assess the wide-ranging mud properties of the SDS modified PEG-SiO2 NC drilling muds. Zeta potential, FTIR, FESEM, EDX, and TGA results indicate that the SDS modified PEG-SiO2 NC was effectively formed and modified, it embodies exceptional thermal stability and is efficiently dispersed. The SDS modified PEG-SiO2 NC has a narrow size distribution range between 82 nm and 410 nm, and a specific surface area of 41.4 m2/g that is sufficiently high for particle-molecule interactions. Its rheological variables are notably shear-thinning and did not undergo notable fluctuation. The filtrate loss of 1.5 g SDS bearing PEG-SiO2 NC at 78 °F and 250 °F was only 5.4 ml and 9.6 ml, against 10.2 ml and 20.5 ml of the WBMs, respectively. High dispersion stability and high thermal stability aided its excellent viscosity and filtration control performance. Moreover, optimum rheological properties for the SDS modified PEG-SiO2 NC drilling muds with Bingham plastic and Ostwald-de-Waele models occurred with mud composition CD3 (CD3 = 1.5 g SDS modified PEG-SiO2 NC + WBM). Thus, this study can help to understand the applications of this nanocomposite as a potential viscosifier and filtrate loss control material for WBMs

Rheological and filtration control performance of water-based drilling muds at different temperatures and salt contaminants using surfactant-assisted novel nanohydroxyapatite

Today, the high-performance rheological and filtration properties of nanosized particles (NPs) in water-based muds (WBMs) are continuously reported. Nevertheless, NP's properties performance at different temperatures and salt environments, specifically the salt-screening process, needs additional knowledge. Hence, this study developed a WBM system using sodium dodecyl sulfate (SDS)-assisted nanohydroxyapatite (Nano-HAp) for different temperatures and salt contaminants. The impacts of the newly-produced Nano-HAp on the density, pH, rheology, and filtration characteristics of WBM at 298 K and 353 K were examined. The effects of salt cations (Ca2+/Na+) on a bentonite-based suspension (BN-WBM) at 298 K and 393 K and SDS-aided Nano-HAp as a salt-tolerant ingredient in drilling muds were also examined. The Herschel-Buckley and Power law models best described SDS-aided Nano-HAp drilling mud's rheology at 298 K and 353 K, respectively. Nano-HAp improved the rheological and filtration capabilities in salt and water solutions at 298 K, 353 K, and 393 K, making it a perfect field additive. 1.0 g of SDS-aided Nano-HAp is recommended, and it is thermally very stable, according to the thermal gravimetric analysis findings. It increased the viscosity performance by 78.6% at 298 K and by 79.2% at 353 K, provided desirable shear stress between 1.0 and 1000 s−1 shear rates, and decreased the fluid loss by 31.8% (≤ 8 mL) at 298 K and 25% (≤ 11 mL) at 353 K. In BN-WBM, it decreased the viscosity of the BN-salt solution from a 35-fold increase to less than a 5-fold increase and made the BN-based suspension less salt-reliant. It operated by attaching to the BN platelets' positive edge and negative face surfaces, shielding Ca2+/Na+ cations from the BN's ion-susceptible regions to decrease the viscosity and filtration of the BN-based suspension. This study demonstrates the possible use of Nano-HAp particles as effective filtration and rheological control additives in WBMs. It further demonstrates that Nano-HAp was appropriate for enhancing the drilling performance of BN-WBMs while increasing their resistance to salt cation contamination