Papers by Keyword: Ethylene Glycol

Abstract: The heat exchanger is an example of heat transfer applications in industries that commonly found in cooling systems and powerplants. The heat exchangers utilise water, oil, and ethylene glycol (EG) as heat transfer fluids which possess a deficiency in heat transfer characteristics. Nanofluid are expected to improve the heat characteristics of the fluid used in heat exchangers. This research used MnFe₂O₄ nanoparticles with a volume fraction of 0.05% into the base fluid. The base fluid is a mixture of EG-water with a concentration of 20; 40; 60; and 80%. This study aims to understand the heat transfer characteristics of the MnFe₂O_4-EG/water nanofluid. The experiments were carried out on a double-pipe heat exchanger with variations flow rate 0.2; 0.4; and 0.6 l/min. This study is expected to show the best performance of MnFe₂O₄-EG/water nanofluid.

Abstract: In this paper, studying synthesis and characterization of ferrospinel nickel ferrite. Nickel ferrite is prepared by using the sol-gel method, with a ratio of 2:1 of iron nitrate to nickel nitrate. First the starting material is dissolved in 100 ml of ethylene glycol solution to get the gel and then the gel was dried at 160°C then calcined at 600°C to obtain fine powder, second the nickel ferrite powder is pressed and sintered at 1200°C. To characterize nickel ferrite are used different techniques, such as: XRD is shown high purity, the purity of the nickel ferrite is known and the extent to which the material is affected by the temperatures of calcination and sintering. FT-IR that is shown absorption band between the elements of the components of nickel ferrite appears. The shape of the resulting powder is known through the SEM, the SEM images showed the spherical shape of the nickel ferrite powder, found the particular size of powder at 600°C ranges between405-264 nm and for sample after sintering at 1200°C ranges between589-353 nm, and our Physical characterization test down.

Abstract: Zeolite have been widely used as gas separation material with its promising properties. One of gas separation technology available is using membrane composites because of its various benefits. A synthesis of membrane composites consists of zeolite/alginate then caried out to study the effect of the addition of Ethylene Glycol (EG) to the CH₄/CO₂ selectivity performance of the membrane. Membrane synthesis varied by its mass ratio of alginate:EG for 1:0, 1:0.25, 1:0.5, 1:1, and 1:2 and evaporated in the room temperature for 72 h. Characterization of the physico/chemical properties was done with various instruments such as FT-IR (Fourier Transform Infra-Red) Spectroscopy, Texture Analyzer, SEM (Scanning Electron Microscopy), and Permeation Test Cell Unit. Addition of EG into the membrane compositions proven to improve the separation performance showed by permeation rate improvement and selectivity value. Gas selectivity separations of CH₄/CO₂ was also investigated and it can be concluded that the synthesized membranes have several promising properties to be used as CH₄/CO₂ separations membranes.

Abstract: In this study, the synthesis and analysis of the crystal structure of silver nanowires (AgNWs) have been performed using the polyol method. In this research, materials used as the main raw material were silver nitrate (AgNO₃). Polyvinyl pyrrolidone (PVP) was used as a capping agent and stabilizer, and Iron (III) Chloride (FeCl₃) for controlling the shape and size of AgNWs. AgNWs were synthesized using two different solvents i.e., ethylene glycol (EG) and propylene glycol (PG). The crystal structure of AgNWs was analyzed using X-ray diffraction (XRD) with a scanning 2θ in the range of 20° to 90°. Furthermore, the structure and electron diffraction patterns were analyzed using transmission electron microscopy (TEM). The XRD pattern of the AgNW sample also has five diffraction peaks, these five diffraction peaks were identified at 38.24°, 44.42°, 64.54°, 77.52°, and 81.68° representing lattice constants (111), (200), (220), (311), and (222), respectively. Based on the results of the calculation of lattice constant values of AgNWs-EG and AgNWs-PG were 4.084 Å. The TEM images of AgNWs-EG have a diameter of 84 to 133 nm, corresponding to the SEM calculation data having a diameter of 109 ± 22 nm. AgNWs-PG has a diameter of 84 to 264 nm. The study results revealed that the results of the characterization performed are interconnected. The XRD characterization results revealed that both samples were crystal-indexed. AgNWs-PG has a larger crystal size than AgNWs-EG.

Abstract: The research objective is to assemble a convection test system which acts as a heat exchanger (HE) and test its applicability using ethylene glycol. A Double Pipe (DP)-type HE consists of an inner pipe surrounded by an outer pipe (annulus) whereas a Coil-type HE composed of a coil surrounded by an outer pipe. Water flows through the outer pipe in both types of HE, while ethylene glycol flows through the inner piper or coil. HE in combination with other components (such as) forms a convection test system. The applicability of the system was tested to determine the heat transfer coefficient of ethylene glycol in a DP-type and Coil-type HEs. After that, the heat transfer rate was calculated and compared. The results show that the heat transfer coefficient in the DP-type HE is the lowest at 12.2 W/m2 oC and the highest at 26.8 W/m2 oC; and the corresponding heat transfer rate is the lowest at 8.3 W and the highest is 56.3 W. In comparison, for Coil-type HE, the lowest heat transfer coefficient is 38.9 W/m2 oC and the highest is 66.2 W/m2 oC which correspond to the heat transfer rate 19.9 W at the lowest and 225 W at the highest.

Abstract: The behaviour of a corrosion inhibitor based on proplolis extract via an iron alloy immersed in an electrolyte containing ethylene glycol water in NaCl 0.1 M was evaluated by a stationary technique not destructive which is the technique of electrochemical impedance. The diameter of the Nyquist curves increases with the increase of the concentration of propolis extract and it reaches an optimum concentration at 1.25 g / L, the maximum surface coverage percent at this concentration is 71.98% .The activation parameters reveal that the inhibitor molecules on iron surface are absorbed by physisorption and a chimisorption and obey Langmuir isotherm adsorption. These results were supplemented by Scanning electron microscopy (SEM) and (EDX) spectrum of chemical composition. The metal solution interface is simulated as a physical model by using electrochemical impedance spectroscopy (EIS). Keywords: Iron Alloy, Propolis extract, ethylene glycol;, Lamgmuir isotherm, Electrochemical impedance Spectroscopy (EIS).

Abstract: Electrolytes in supercapacitors (SCs) play an important role on their energy storage capacity. The electrochemical stability of electrolytes defines the operating potential of the SCs and their viscosity defines a power density of the SCs. In the present work, a new method for composing an electrochemically stabile but high viscous ethylene glycol (EG) based electrolyte has been discussed. A viscosity of the EG then reduced by dissolving an inorganic lithium tetrafluoroborate (LiBF₄) salt. The affect of the concentration of the salt on EG viscosity has been investigated. The best capacitive performance of activated carbon (AC) based electrodes with large operating potential (-1.7V to 1.7V) was found in 3M LiBF₄/EG electrolyte.

Abstract: The inherent irreversibility of a variable viscosity ethylene glycol/silver (EG/Ag) nanofluid single-phase Poiseuille flow in a vertical microchannel with convective cooling under the combined influence of buoyancy force, nonlinear thermal radiation, nanoparticles shape and volume fraction is investigated. The nonlinear model equations are obtained and numerically solved via shooting method with Runge-Kutta-Fehlberg integration scheme. Pertinent results with respect to the effects of emerging thermophysical parameters on the nanofluid velocity, temperature, skin friction, Nusselt number, thermal stability criteria, entropy generation rate and Bejan number are presented graphically and discussed. It is observed that thermal radiation, Biot number and buoyancy force boost the release of heat energy thereby cooling the flow system. Meanwhile, an increase in nanoparticles volume fraction lessens the entropy generation rate which augment the exergetic effectiveness and thermal stability of the flow system.

Abstract: High aspect ratio silver nanowires (AgNWs) with an average length of 40 μm and average diameter of 88 nm were successfully synthesized using waste ethylene glycol as solvent and reducing agent. Silver nanowires with an average length and diameter of 32 μm and 122 nm, were produced after the third cycle of being reused. A transparent conducting film with a sheet resistance of 69 Ω/sq and optical transmittance of 91% was fabricated by Meyer rod coating an ink formulation of AgNWs dispersed in hydroxyethyl celullose (HEC)/methanol/deionized water. The low resistance of the AgNW networks was maintained even after 1000 bending cycles due to HEC acting as binder for the nanowires. The AgNWHEC transparent conductive electrode performed better than bare AgNWs and indium tin oxide (ITO) on polyethylene terephthalate (PET) substrate after several bending cycles. The AgNW-HEC electrode also showed excellent stability against corrosion.

Abstract: Hybrid nanofluid is the new generation of heat transfer fluid for various heat transfer applications where transport characteristics are substantially higher than the base liquid. The study presents an experimental investigation of rheological and thermophysical properties of Al₂O₃/ CuO hybrid nanoparticles suspended in 25:75 (by weight) ethylene glycol and water mixture. This manuscript presents experimental work of thermophysical properties of Al₂O₃/CuO/water/ethylene glycol hybrid nanofluids and its effect on thermal efficiency of flat plate solar collector. Nanofluids of particle volume percentage of 0.5%, 1%, 1.5% and 2% were tested. Results show that thermal conductivity, viscosity and density increases with nanoparticles concentration. The efficiency of the collector was improved by 45% by increasing the nanoparticle weight fraction.