171 research outputs found
Performance of Membrane-Assisted Solid Oxide Fuel Cell System Fuelled by Bioethanol
The membrane separation units for bioethanol purification including pervaporation and vapor permeation are integrated with the bioethanol-fuelled solid oxide fuel cell (SOFC) system. The preliminary calculations indicate that Hydrophilic type is a suitable membrane for vapor permeation to be installed after a hydrophobic pervaporation. Based on energy self-sufficient condition and data of available pervaporation membranes, the simulation results show that the use of vapor permeation unit after the pervaporation can significantly improve the overall electrical efficiency from 10.96% for the system with pervaporation alone to 26.56%. Regarding the effect of ethanol recovery, the ethanol recovery at 75% can offer the optimal overall efficiency from the proposed purification system compared to the ethanol recovery at 31.16% for the case with the single pervaporation
Review of Non-Thermal Plasma Technology for Hydrogenation of Vegetable Oils and Biodiesel
The hydrogenation of lipid derivative compounds has received much attention as it is one of the key chemical reactions of industrial processes to improve the physical and chemical properties of those compounds such as thermal resistance, cold flow properties, oxidative stability, etc. The principle of hydrogenation of vegetable oil for margarine production relies on the addition of hydrogen to the carbon double bond positions of fatty acid molecules to become a single bond, increasing the saturated fatty acids until the texture becomes semi-solid. The partial addition of hydrogen to biodiesel improves its oxidation resistance. At present, industrial-scale using catalytic hydrogenation of lipid derivative compounds operates under high temperature and high-pressure environments, leading to a high trans-fat content in the products and requiring catalyst separation from the product. Non-thermal plasma (NTP) technology as a green process can be deployed to substitute conventional hydrogenation, on a laboratory scale for the time being, because no catalyst is required and the process can occur at near ambient temperature and low or atmospheric pressure. Moreover, trans-fat formation is several times lower than that of catalytic hydrogenation. The present review article provides more insight into the various types of NTP technology for lipid derivative compounds hydrogenation, including discussions on different experimental setup configurations, parameters affecting plasma hydrogenation, properties of synthesized products, as well as the advantages and drawbacks of environmentally-friendly plasma hydrogenation compared to conventional catalytic hydrogenation
Reviews on Solid Oxide Fuel Cell Technology
oai:www.engj.org:article/25Solid Oxide Fuel Cell (SOFC) is one type of high temperature fuel cell that appears to be one of the most promising technology to provide the efficient and clean energy production for wide range of applications (from small units to large scale power plants). This paper reviews the current status and related researches on SOFC technologies. In details, the research trend for the development of SOFC components(i.e. anode, electrolyte, cathode, and interconnect) are presented. Later, the current important designs of SOFC (i.e. Seal-less Tubular Design, Segmented Cell in Series Design, Monolithic Design and Flat Plate Design) are exampled. In addition, the possible operations of SOFC (i.e. external reforming, indirect internal reforming, and direct internal reforming) are discussed. Lastly, the research studies on applications of SOFCs with co-generation (i.e. SOFC with Combined Heat and Power (SOFC-CHP), SOFC with Gas Turbine (SOFC-GT)) and SOFC with chemical production) are given
Liquid-liquid phase equilibria of aqueous biphasic systems based on glycerol formal:Application on tetracycline recovery from water
Biopharmaceuticals are commonly present in relatively low concentrations in aqueous solutions, making their detection and purification detrimental. In this work, we used novel aqueous biphasic systems based on glycerol formal (GF) to extract an important antibiotic - tetracycline. We report cloud points (solubility curve) and tie-lines for three ternary systems, containing GF, water, and inorganic salt (either K3PO4, K2HPO4, or K2CO3) at constant temperature of 298 K and at 0.1 MPa. The tie-line data of these ternary systems were correlated using the nonrandom two-liquid model, and binary interaction parameters of activity coefficients were estimated. The experimental and correlated tie-line data were compared in terms of average root-mean-square deviation and showed satisfactory agreements. The partition coefficients of tetracycline between two phases were measured, and corresponding extraction efficiencies were calculated. The maximum value of partition coefficient was 1551 for the system containing K3PO4, followed by values of 1145 and 927 for systems containing K2CO3 and K2HPO4, respectively. The calculated extraction efficiencies were very high - greater than 98.8%, demonstrating high potential for using aqueous biphasic systems based on GF for separation and purification processes
Performance Assessment of SOFC Systems Integrated with Bio-Ethanol Production and Purification Processes
The overall electrical efficiencies of the integrated systems of solid oxide fuel cell (SOFC) and bio-ethanol production with purification processes at different heat integration levels were investigated. The simulation studies were based on the condition with zero net energy. It was found that the most suitable operating voltage is between 0.7 and 0.85 V and the operating temperature is in the range from 973 to 1173 K. For the effect of percent ethanol recovery, the optimum percent ethanol recovery is at 95%. The most efficient case is the system with full heat integration between SOFC and bio-ethanol production and purification processes with biogas reformed for producing extra hydrogen feed for SOFC which has the overall electrical efficiency of 36.17%. However more equipment such as reformer and heat exchangers are required and this leads to increased investment cost
Process and Energy Intensification of Glycerol Carbonate Production from Glycerol and Dimethyl Carbonate in the Presence of Eggshell-Derived CaO Heterogeneous Catalyst
The process and energy intensifications for the synthesis of glycerol carbonate (GC) from glycerol and dimethyl carbonate (DMC) using an eggshell-derived CaO heterogeneous catalyst were investigated. The transesterification reaction between glycerol and DMC was typically limited by mass transfer because of the immiscible nature of the reactants. By varying the stirring speed, it was observed that the mass transfer limitation could be neglected at 800 rpm. The presence of the CaO solid catalyst made the mass transport-limited reaction process more prominent. Mass transfer intensification using a simple kitchen countertop blender as an alternative to overcome the external mass transfer limitation of a typical magnetic stirrer was demonstrated. A lower amount of the catalyst and a shorter reaction time were required to achieve 93% glycerol conversion or 91% GC yield, and the turnover frequency (TOF) increased almost 5 times from 1.5 to 7.2 min−1 when using a conventional magnetic stirrer and countertop blender, respectively. In addition, using a simple kitchen countertop blender with 7200 rpm, the reaction temperature of 60 °C could be reached within approximately 3 min without the need of a heating unit. This was the result of the self-frictional heat generated by the high-shear blender. This was considered to be heat transfer intensification, as heat was generated locally (in situ), offering a higher homogeneity distribution. Meanwhile, the trend toward energy intensification was promising as the yield efficiency increased from 0.064 to 2.391 g/kJ. A comparison among other process intensification techniques, e.g., microwave reactor, ultrasonic reactor, and reactive distillation was also rationalized
Extraction of Lead Ions and Partitioning Behaviour in Aqueous Biphasic Systems Based on Polyethylene Glycol and Different Salts
Lead ions are environmental pollutants often present in very low concentrations, which makes them difficult to detect and, thus, present problems for environmental monitoring. In this study, we examined the performance of aqueous biphasic systems based on polyethylene glycol (PEG, molecular mass of 4000 g mol–1) with ammonium sulfate (NH4)2SO4, magnesium sulfate (MgSO4), sodium sulfate (Na2SO4), and trisodium citrate (Na3C6H5O7) for the separation of lead(II) ions from aqueous solutions. We investigated the effects of salt types and the ratio of PEG4000 to salt on the extraction efficiency of lead(II) removal at constant temperatures of 303 K and 0.1 MPa. Additionally, we determined the cloud points (solubility equilibrium curve) and tie-lines for four ternary systems comprising PEG4000, water, and salt (either (NH4)2SO4, MgSO4, Na2SO4, or Na3C6H5O7) under the same conditions. A maximum lead(II) extraction efficiency of 74.4% was achieved using the PEG4000/(NH4)2SO4 system with a mass fraction ratio of PEG4000 to (NH4)2SO4 of 0.2:0.12. This outcome highlights the significant potential of utilizing aqueous biphasic systems based on PEG4000 to separate lead(II) from aqueous solutions efficiently
Fungal fermented palm kernel expeller as feed for black soldier fly larvae in producing protein and biodiesel
Being the second-largest country in the production of palm oil, Malaysia has a massive amount of palm kernel expeller (PKE) leftover. For that purpose, black soldier fly larvae (BSFL) are thus employed in this study to valorize the PKE waste. More specifically, this work elucidated the effects of the pre-fermentation of PKE via different amounts of Rhizopus oligosporus to enhance PKE palatability for the feeding of BSFL. The results showed that fermentation successfully enriched the raw PKE and thus contributed to the better growth of BSFL. BSFL grew to be 34% heavier at the optimum inoculum volume of 0.5 mL/10 g dry weight of PKE as compared to the control. Meanwhile, excessive fungal inoculum induced competition between BSFL and R. oligosporus, resulting in a reduction in BSFL weight. Under optimum feeding conditions, BSFL also registered the highest lipid
yield (24.7%) and protein yield (44.5%). The biodiesel derived from BSFL lipid had also shown good compliance with the European biodiesel standard EN 14214. The high saturated fatty acid methyl esters (FAMEs) content (C12:0, C14:0, C16:0) in derived biodiesel made it highly oxidatively stable.
Lastly, the superior degradation rate of PKE executed by BSFL further underpinned the sustainable conversion process in attaining valuable larval bioproducts
Supporting Clean Energy in the ASEAN: Policy Opportunities from Sustainable Aviation Fuels Initiatives in Indonesia and Malaysia
Sustainable aviation fuels is a strategic long-term solution for zero-carbon aviation industry by 2050, thus underscoring the need to accelerate the deployment through reforms in the relevant key areas. Aligned to the agenda, this paper aims to study the policy opportunities for drop-in sustainable aviation fuel (SAF) deployment in the ASEAN by considering the initiatives undertaken. by Indonesia and Malaysia. Four areas are used as coding framework to assess the current status, challenges, and policy opportunities, namely (1) policy, strategy, and reforms; (2) standards and certification system; (3) economic instruments; and (4) international integration. First, the current status and challenges within each country is assessed. Indonesia has shown a more command-and-control approach with an upfront SAF blending mandate. However, it needs to be supported by several compliance measures. Malaysia, on the other hand, has conducted country assessments but no SAF-specific policy has been issued yet. Both countries still lack the economic instruments, while international integration is still relatively under-explored with only limited inter-regional partnerships. As the biggest palm-oil producing countries, Indonesia and Malaysia possess enormous potentials to lead the region in deploying SAF, thus more initiatives are urged
- …