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ASEAN Journal of Chemical Engineering
Published by Universitas Gadjah Mada
ISSN : 26555409     EISSN : 26555409     DOI : https://doi.org/10.22146/ajche.52004
Core Subject : Science, Engineering,
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry
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
Arjuna Subject : Teknik Kimia (semua kategori) - Kimia Proses dan Teknologi
Articles 372 Documents
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Utilization of Mathematical Software Packages in Chemical Engineering Research Ang Wee Lee; Nayef Mohamed Ghasem; Mohamed Azlan Hussain
ASEAN Journal of Chemical Engineering Vol 5, No 2 (2005)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.50180

Abstract

Using Fortran taken as the starting point, we are now on the sixth decade of high-level programming applications. Among the programming languages available, computer algebra systems (CAS) appear to be a good choice in chemical engineering can be applied easily. Until the emergence of CAS, the assistance from a specialized group for large-scale programming is justified. Nowadays, it is more effective for the modern chemical engineer to rely on his/her own programming ability for problem solving. In the present paper, the abilities of Polymath, Maple, Matlab, Mathcad, and Mathematica in handling differential equations are illustrated for differential-algebraic equations, large system of nonlinear differential equations, and partial differential equations. The programming of solutions with these CAS are presented, contrasted, and discussed in relation to chemical engineering problems. Keywords: Computer algebra systems (CAS),computer simulation,Mathcad, Mathematica,Mathlab and numerical methods.
Photodegradation Kinetics of Phenol and Methylene Blue Dye Present in Water Stream Over Immobilized Film Ti02 Catalyst Chin Mei Ling; Abdul Rahman Mohamed; Subhash Bhatia
ASEAN Journal of Chemical Engineering Vol 5, No 2 (2005)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.50181

Abstract

A photocatalytic reactor has been designed to study the kinetics of photocatalytic degradation of phenol and methylene blue dye present in water stream on immobilized Ti02 catalyst. The principal part of the reactor consisted of a cylindrical pyrex glass tube whose outer surface was coated with the synthetic Ti02 film catalyst prepared from sol-gel technique. An ultraviolet light lamp of 365 nm wavelength was set longitudinally in the center of the tube. The synthetic Ti02 film formulation with the molar ratio of 1 titanium isopropoxide : 8 isopropanol: 1.1 H20: 3 acetyl acetone: 0.05 acetic acid was used to develop the immobilized Ti02 film catalyst deposited over the glass support. The performance of the immobilized photocatalytic reactor was evaluated by studying the decomposition kinetics of phenol and methylene blue dye present in the aqueous stream. The kinetics of photocatalytic degradation of phenol and methylene blue obeyed first order heterogeneous equation. The kinetic parameters were evaluated from the kinetic data using the Langmuir"Hinshelwood-Hougen-Watson (LHHW) model. Keywords: Kinetics, methylene blue, phenol, photocatalytic reactor, and Ti02 film catalyst.
Ranking of Waste Management Options Under Conditions of Possibilistic Uncertainty Using Fuzzy SAW Raymond Girard R. Tan
ASEAN Journal of Chemical Engineering Vol 5, No 2 (2005)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.50182

Abstract

Integrated waste management involves the use of appropriate techniques ranging from pollution prevention/cleaner production (P2/CP) to conventional end-of-pipe controls. Design or retrofit of process plants usually entails selection of an optimal waste management measure from a number of alternatives. The selection process involves consideration of multiple criteria and data uncertainty, the latter being arguably possibilistic (fuzzy) rather than probabilistic (random) in nature. A fuzzy simple additive weighting (SAW) algorithm is proposed for such problems and demonstrated on a case study. The principal feature of the techniques shown is the retention of fuzzy confidence levels during the assessment of different technological options. Keywords:Cleaner production, fuzzynumbers, pollutioncontrol, pollution prevention, and possibility theory.
NO Reduction by Carbon Monoxide Over Cobalt on ZeoliteBeta Nurak Grisdanurak; Benjamart Nuntaitawegon; Gerald Kinger; Hannelore Vinek
ASEAN Journal of Chemical Engineering Vol 5, No 2 (2005)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.50183

Abstract

This study focused on the selective catalytic reduction of nitric oxide (NO) by carbon monoxide (CO) over cobalt supported on zeolite beta (CoIBEA) with and without the presence of oxygen or water. The Co/BEA catalyst with 2.6% metal loading was prepared by solid state ion exchange from freshly synthesized HBEA and CoCl2'6H20. The adsorption behavior of NO on CoIBEA investigated by temperature programmed desorption (TPD) revealed two peaks for NO at 100 and 260°C indicating that there were at least two adsorption modes. The desorption of CO completed near 200°C along with a small amount of C02. The activity of ColBEA catalyst for NO reduction by CO was lower than 20% at 100-300°C but higher than 50% at 400-500°C with the maximum conversion of 60% at 500°C. Products were selectively N2 and C02. However, the activity in the presenceof oxygen was low due to the more favorable reaction between CO and 02 to form C02. The catalytic activity in the presence of water was also low but higher than that in the presence of oxygen. Keywords: NO reduction by CO, cobalt on zeolite beta, and solid state ion exchange.
Effect of Basis Sets on the Selection of the Level of Theory Toward the Development of Quantum-Based Force Field Equation for Ionic Liquids A. N. Soriano; B. T. Doma, Jr.
ASEAN Journal of Chemical Engineering Vol 5, No 2 (2005)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.50184

Abstract

The chemical industry is under considerable pressure to replace many of the volatile organic compounds. Volatile organic compounds are a major contributor to air pollution, but out of necessity, they are still frequently used in many chemical and industrial processes. A new class of solvents, referred to as ionic liquids, may offer at least a partial solution to the pollution problem caused by volatile organic compounds. Ionic liquids are generally considered "green" solvents because of their environment-friendly properties. However, the main problem that hinders the chemical industry from using ionic liquids is that, compared to conventional organic solvents, relatively little is known about their thermodynamic and transport properties. Since there are large possible combinations of ionic liquids, it would be very expensive if the study were conducted in the laboratory. The more appropriate approach in studying the properties of ionic liquids is to engage in a computational method, which uses a computer software that evaluates ionic liquids' thermophysical quantities via quantum mechanical and molecular mechanical simulations. In this study, a computer simulation, with the aid of SPARTAN '02 software, is used to study the effect of basis sets on the selection of the appropriate level of theory, which would be employed later in developing a quantum-based force field equation for predicting the properties of ionic liquids. Using the Hartree-Fock self-consistent filled (HF-SCF) molecular orbital model with different basis sets, a single point energy calculations were carried out for the chosen ionic liquid. With the exception of the minimal basis set, the SCF total energies for the other basis sets agree with each other in terms of magnitude. The SCF total energy is not affected as the basis set varies from minimal to split valence and as it polarizes. The most appropriate basis set was found to be 6-31G*. Keywords: Basis sets, Hartree-Fock, ionic liquids, force field equation, level of theory, and SPARTAN '02.
Integrating Performance Indicator Into the Audit Process Safety Management System C. R. Che Hassan; M. J. Pitt; A. J. Wilday
ASEAN Journal of Chemical Engineering Vol 5, No 2 (2005)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.50185

Abstract

The development of the audit method has included the identification of possible performance indicators at each level of the sociotechnical pyramid for a range of areas of work in which accidents have been shown to occur most frequently. The measurementof performance indicators is part of a feedback loop which causes safety improvements. Integration of performance indicators into the audit system has been tested at three operating chemical industries in Terengganu and Selangor in Malaysia. A summary of the weaknesses of the similar elements identified in the three audited plants is presented. Analysis on the approach used enables the identification of deficiencies in safety management aspects. Keywords: Accidents, audit, deficiencies, performance indicators, safety management, and sociotechnical pyramid.
Kinetic Consideration of Clinker Formation in Portland Cement Production Using Demolition Rubbles (Concrete,mortar and plaster) Part I : Burning Ability of Raw Mixes Sumardi P; I. B. Agra; I. M. Bendiyasa; Wahyudi B. S.
ASEAN Journal of Chemical Engineering Vol 5, No 2 (2005)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.50186

Abstract

Wahyudi B.S.Wahyudi B.S.In general, the main raw materials in Portland cement production are limestone, clay, and corrective materials such as iron sand and silica sand. These raw material come from natural deposits, which are very hard to find in some countries. In this research, Portland cement was made by utilizing the demolition rubble of office and housing buildings. The rubble consists of concrete wastes (mixtures of hydrated Portland cement minerals and some aggregates) and some building bricks as well as mortar/plaster of Portland cement. To meet the cement modulus, which is generally used in Portland cement industries, corrective materials such as limestone (source of CaO) and disposed building bricks are used. The term burning ability is used for Portland cement to measure the CaO free content in the cement clinker produced from specified raw material mixes at a specific operating 'condition of clinkering. The cement modulus used is Ume Saturation Factor (LSF) and Silica Modulus (SM). The minimum Cao free content was found by using LSF: 0.86, SM: 2.14, and clinkering temperature 14000C for 30 minutes. The cement modulus was made from concrete waste, limestone, and disposed red brick with a weight ratio of 1: 3.489: 0.677. Keywords: Burning ability,demolition rubble of buildings, Portland cement, and raw mixes.
Propane Dehydrogenation in a Modified Porous Membrane Reactor for Producing Propylene with Chemical and Polymer Grades Azis Trianto; Yazid Bindar; Noezran Noezran
ASEAN Journal of Chemical Engineering Vol 5, No 2 (2005)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.50187

Abstract

Propane dehydrogenation is a promising route for producing propylene to replace traditional cracking methods. A membrane reactor offers a possibility to produce not only chemical grade but also polymer grade of propylene. The purpose of the present study is to evaluate the performance of a Modified Porous Membrane Reactor (MPMR) in producing these two propylene grades simultaneously. The study involves evaluations based on thermodynamics and process flow sheeting. The performance of this reactor is compared to that of conventional reactor. At first, the thermodynamics is conducted using minimum Gibb's Energy approach. Then the process flow sheeting evaluation is built using the HYSYS simulator. The effect of inert gas (steam) concentration in both sweep and feed sides is investigated. The thermodynamics study results optimum temperature and inert gas concentration to obtain these two grades of propylene simultaneously. The propylene with polymer grade above 99% is produced from the sweep side outlet. The propylene with chemical grade is produced from the feed side outlet. The simultaneous production of these two grades of propylene has benefit in vanishing propane-propylene splitter. Keywords: Membrane reactor, porous membrane, propane dehydrogenation, propylene production, and process simulation.
Hydrolytic Process of Proteins in Moringa oleifera Seeds in Varied Concentrations of Sodium Hydroxide and Hydrochloric Acid Ika Kurniaty; Ratri Ariatmi Nugrahani; Fatma Sari; Wenny Diah Rusanti; Haryadi Wibowo
ASEAN Journal of Chemical Engineering Vol 19, No 2 (2019)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (689.3 KB) | DOI: 10.22146/ajche.50383

Abstract

Indonesia is endowed with an immense biodiversity that can be used as protein sources. One of these is Moringa oleifera tree that is locally known as Kelor. The seeds of this plant can be used as a protein source, an effective coagulant for water purification, a natural absorbent, and an antimicrobial treatment. Kelor seeds are known to contain fibers, proteins, carbohydrates, and vitamins. The objectives of this study were to identify the optimal solution concentration, determine the yield percentage, and determine the optimal protein content from hydrolytic processes of Moringa seed extraction using Sodium Hydroxide (NaOH) and Hydrochloric Acid (HCl). The hydrolysis took place for 30 minutes at 60oC. The proteins extracted from Moringa seeds were identified with biuret and Braford tests. The NaOH extractions resulted in the highest yield of 12.1% and protein content of 0.43% with 2% NaOH. Whereas those of HCl produced the highest yield of 11.1% and protein content of 9.63% with 1% HCl.
Microwave-Assisted Extraction of Polyphenol Content from Leaves of Tristaniopsis merguensis Griff. Robby Gus Mahardika; Occa Roanisca
ASEAN Journal of Chemical Engineering Vol 19, No 2 (2019)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (790.864 KB) | DOI: 10.22146/ajche.50448

Abstract

Tristaniopsis merguensis Griff. is a species of the Myrtaceae family and has been widely used by people of Bangka Belitung as a traditional medicine to reduce cholesterol, gastric pains, and improve cardiac performance. Extraction methods are the crucial efficacy of herbal medicine. The conventional method, like maceration, takes a long time. In this study, the leaves of Tristaniopsis merguensis were extracted using Microwave-Assisted Extraction (MAE) to reduce extraction time. The extraction using MARS (Microwave Accelerated Reaction System) 6 by CEM Corporation with time variation times of 5, 10, 15, 30 min with temperature of 60, 80, 100oC at 1200 W. The yield using acetone extraction of Tristaniopsis merguensis leaves increases with time and temperature. The extraction dependent on solvent extraction, polar solvent like ethanol, and methanol were higher than semi-polar solvents like acetone and ethyl acetate. The polyphenol content of acetone extract using MAE (10 min, 80oC) was found to be 234.67 mg Gallic Acid Equivalent per gram (GAE/g); it was higher than acetone extract using maceration. The phytochemical results show there are no difference in the active compound using MAE and maceration, i.e. alkaloids, tannin, and flavonoids. Yield extraction, time, and phytochemical results of MAE are more favorable than a maceration.

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