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Contact Name
Ari Pramudyantoro
Contact Email
ajche.ft@ugm.ac.id
Phone
+62274555320
Journal Mail Official
ajche.ft@ugm.ac.id
Editorial Address
Jln. Grafika No. 2 Kampus UGM Yogyakarta Indonesia 55281
Location
Kab. sleman,
Daerah istimewa yogyakarta
INDONESIA
ASEAN Journal of Chemical Engineering
ISSN : 26555409     EISSN : 26555409     DOI : https://doi.org/10.22146/ajche.52004
The ASEAN Journal of Chemical Engineering publishes papers on Chemical Engineering, specifically but not limited to the areas of thermodynamics, reaction kinetics, transport phenomena, process control, environment, energy, biotechnology, corrosion, separation science, powder technology, materials science, and chemical engineering education
Articles 7 Documents
Search results for , issue "Vol 13, No 1 (2013)" : 7 Documents clear
Effects of Vacuum Drying on Structural Changes of Banana Slices Wannapit Junlakan; Ram Yamsaengsung; Supawan Tirawanichakul
ASEAN Journal of Chemical Engineering Vol 13, No 1 (2013)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1048.835 KB) | DOI: 10.22146/ajche.49719

Abstract

The objective of this research was to study the optimum condition for the vacuum drying of banana slices using a vacuum dryer and to find out the appropriate thin layer equation for predicting the drying kinetic of bananas. The experiments were carried out at the drying temperatures of 60, 70, 80 and 90oC and absolute chamber pressure of 30 mmHg. The drying experiments were performed until the samples moisture content was lower than 3.4% (w.b.). Next, the dried products were analyzed for physical quality (in terms of color, shrinkage, and texture) and sensory quality (in terms of color, texture, flavor, crispness and overall acceptability). These data were used in choosing the optimum condition for the vacuum drying of banana slices. From experimental results, the drying time at the highest drying temperature was the shortest. At this condition, the dried banana slices showed the highest degree of yellowness, lower shrinkage, and more crispness compared to lower drying temperatures. From sensory analysis, each drying condition showed significant effect on consumer acceptability with the drying temperature of 70, 80 and 90oC showing the levels of the overall acceptability sensory qualities of dried banana is not significantly different. Consequently, the drying temperature of 90oC was suggested as the best drying condition for sliced bananas. Moreover, three mathematical models (Newton, Logarithmic and Page) describing thin layer drying were investigated. It was found that the thin layer equation providing the highest coefficient of determination (R2) and the lowest chi-square (X2) and root mean square error (RMSE) was the Logarithmic equation.
Thermomechanical Properties of KevlarTM Reinforced Benzoxazine-Urethane Alloys Rimdusit S Rimdusit S; Kasemsiri P. Kasemsiri P.; Okhawilai M. Okhawilai M.
ASEAN Journal of Chemical Engineering Vol 13, No 1 (2013)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (774.403 KB) | DOI: 10.22146/ajche.49720

Abstract

Ballistic armor is one of an important application which required high performance of fiber-reinforced polymer due to its outstanding specific mechanical properties. Therefore, KevlarTM reinforced benzoxazine-urethane alloys as ballistic impact resistance composites were developed in this research. The polybenzoxazine alloy composites were fabricated by compression molding at 200ºC and 5 MPa by a compression molder. The amount of urethane fraction in the alloy matrix was ranging from 0-40wt% while the fiber content was kept constant at 80wt%. The mechanical properties of the matrix alloys and their KevlarTM fiber composites were characterized by dynamic mechanical analysis and universal testing machine. The results revealed that storage modulus at room temperature of the composites was reduced from 16.82 GPa when using the neat polybenzoxazine as a matrix to the value of 11.89 GPa at 40wt% of urethane content in the alloy matrix. Moreover, the more urethane in the alloy matrix resulted in lower flexural modulus of the KevlarTM composites i.e. 22 GPa when using the neat polybenzoxazine as a matrix to the value of 12 GPa when using 40wt% of urethane in the alloy matrix. Interestingly, glass transition temperature (Tg) obtained from the maximum peak of the loss modulus was observed to be in the range of 187-247ºC, which was significantly higher than those of the two parent polymers. Furthermore, the activation energy of the alloys was found to increase with increasing urethane content, which corresponded to the observed Tg value enhancement. The observed synergism in Tg of KevlarTM reinforced benzoxazine-urethane was an outstanding characteristic for a wide range of applications, which requires high thermal stability.
Effect of Ethylene-Vinyl Acetate Copolymer on Properties of Acrylonitrile-Butadiene-Styrene/Zinc Oxide Nanocomposites Sirirat Wacharawichanant; Lalitwadee Noichin; Sutharat Bannarak
ASEAN Journal of Chemical Engineering Vol 13, No 1 (2013)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (864.827 KB) | DOI: 10.22146/ajche.49721

Abstract

Mechanical and morphological properties of acrylonitrile-butadiene-styrene (ABS)/zinc oxide (ZnO) nanocomposites used ethylene-vinyl acetate copolymer (EVA) as compatibilizer were investigated. The ABS/ZnO nanocomposites without and with EVA 4 wt% were prepared by melting-blend with an internal mixer. The results showed that the addition of ZnO nanoparticles did not improve the mechanical properties of ABS/ZnO nanocomposites. The impact strength of the ABS/ZnO nanocomposites decreased with increasing ZnO content. The addition of EVA in ABS showed a decrease the impact strength but increased after adding ZnO in ABS/EVA matrix. The ABS/ZnO nanocomposites with EVA was higher the percent strain at break, but lower Young’s modulus, tensile strength and impact strength than the neat ABS and ABS/ZnO nanocomposites. The percent strain at break of ABS/ZnO nanocomposites increased with incorporation of EVA all ZnO compositions. However, the poor compatibility between ethylene in EVA and ABS matrix reduced as most of the mechanical properties of ABS/EVA/ZnO nanocomposites. The ZnO particle distributions in nanocomposites were studied by scanning electron microscopy (SEM), which observed that ZnO particles agglomerated in ABS and ABS/EVA matrix. The fractured surfaces of impact test samples were also observed through SEM and revealed that the ductile fracture of ABS was converted to brittle fracture with addition of ZnO.
Removal of Acid Blue 158 from Solution by Sunflower Seed Hull Siriwan Srisorrachatr; Paranee Sriromreun
ASEAN Journal of Chemical Engineering Vol 13, No 1 (2013)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1048.665 KB) | DOI: 10.22146/ajche.49722

Abstract

The removal of Acid Blue 158, acid dye for textile dyeing, from aqueous solution by sunflower seed hull was studied. The extent of adsorption capacity was studied as a function of heating temperature, sulphuric acid treatment, adsorbent size and pH of the solution. Sunflower seed hull was heated at 200, 300 and 400oC in oxygen deficient conditioned furnace. As the results, the sunflower seed hull heated at 200oC was the best absorbent for the dye removal with the maximum value of 30.84% at pH 4. Furthermore, removal ratio of Acid Blue 158 increased when the adsorbent was treated with 2M sulphuric acid. Particle sizes examined in this study were 250-355, 710-2000 and over 2000 micrometer. It was showed that the size of adsorbent affected on the removal capacity, i.e. the removal capacity increased along with the decrease of the size of absorbent. pH of the solution was studied between 1 and 6, and it was found that the optimum pH was pH 2. At the optimum condition, the modified adsorbent showed the removal ability of about 50%. The results obtained under the conditions of pH 4, 2M H2SO4 treatment of sunflower seed hull and the size of 500-710 micrometer at room temperature, the adsorption isotherm was fitted to Langmuir adsorption model, and the maximum adsorption capacity, qm, of 18.52 mg/g and Langmuir adsorption constant, Kl, of 5.25x10-3 L/mg were obtained.
The Initial Dioxigenase Gene Squences Analysis of Marine Bacteria Strain M128 Muhamad Sahlan; Hanif Yuliani; Heri Hermansyah; Anondho Wijanarko
ASEAN Journal of Chemical Engineering Vol 13, No 1 (2013)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (953.401 KB) | DOI: 10.22146/ajche.49723

Abstract

Biodegradation of polyaromatic hydrocarbons (PAHs) are catalyzed by multicomponent enzymes from microbe. The initial dioxygenase was used as a key enzyme for attacking the aromatic ring structure of PAHs, furthermore its initial dioxygenase gene was used to select PAHs degrading bacteria. Marine bacteria M128 strain could grow on medium contained PAHs. Detection of its cellular initial deoxygenase gene was done by nahAc gene amplification. The nahAc gene commonly used as biomarkers of PAH degradation, and as a result, nahAc gene sequence analysis of marine bacteria M128 strain was similar to naphthalene dioxygenase of Pseudomonas genera with 99% homology.
Synthesis of Ternary Homogeneous Azeotropic Distillation Sequences: 2. Flowsheet Identification Sutijan Sutijan; Megan Jobson; Robin Smith
ASEAN Journal of Chemical Engineering Vol 13, No 1 (2013)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1102.008 KB) | DOI: 10.22146/ajche.49724

Abstract

This paper presents a systematic methodology for flowsheet generation for separating binary azeotropic mixtures using homogeneous azeotropic distillation. A new classification system for ternary mixtures using ‘standard distillation line maps’ defined in Sutijan et al. (2012) is employed. The new characterisation system is able to link candidate entrainers to flowsheet structures which can facilitate the separation. The sequences considered include pressure-swing distillation, two and three-column flowsheets with or without boundary crossing and the use of single and double-feed columns. For a given ternary mixture, suitable flowsheet structures that can facilitate the separation can be automatically identified. The method is illustrated using examples.
Evaluating Climate Change Mitigation Options in the Philippines with Analytic Hierarchy Process (AHP) Michael Angelo B. Promentilla; Carla Angeline M. De la Cruz; Katrina C. Angeles; Kathrina G. Tan
ASEAN Journal of Chemical Engineering Vol 13, No 1 (2013)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (977.123 KB) | DOI: 10.22146/ajche.49725

Abstract

The environmental problem of climate change is an issue that needs to be addressed worldwide. As the electricity-generating power sector is the largest contributor of CO2 in the country, low-carbon technologies or sustainable energy systems are being considered as viable alternatives to reduce the CO2 emissions from this sector. These are fossil-based power plants with carbon capture and storage (F-CCS) technology, nuclear energy (NE) and renewable energy (RE) technologies, particularly solar energy (SE), wind energy (WE), hydroelectricity (HE), geothermal energy (GE) and biomass (BE). However, successful implementation of any of these CCMOs depends not only on the technical and economic aspect but also the socio-political aspect of the project. This study therefore proposes an analytical decision modeling framework to evaluate these options by incorporating the subjective judgment of stakeholders. The Analytic Hierarchy Process (AHP) was used to structure the problem and quantify the relative preference of each option with respect to four criteria namely environmental effectiveness (EE), economic viability (EV), technical implementability (TI), and social acceptability (SA).Results from the decision model indicate that the most important criterion is environmental effectiveness, and the least important is social acceptability. With respect to environmental effectiveness, their most preferred CCMO was solar energy whereas their least preferred is nuclear energy mainly because of the risk posed by the generated nuclear wastes. With respect to economic viability, their most preferred CCMO was geothermal energy, and the least preferred was nuclear energy. With respect to technical implementability, the respondents gave the highest preference weight on geothermal energy and the least preferred is nuclear energy. With respect to social acceptability, the most preferred was wind energy and again, the least preferred was nuclear energy.

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