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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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Effect of Carrier Agents and Operational Parameters on the Physical Quality of Spray-Dried Tomato Powder: A Review S M Anisuzzaman; Collin G. Joseph; Janice L. H. Nga; Fatin Nadiah Ismail
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.71487

Abstract

Tomatoes are one of the most frequently consumed crops in the world, and they can be cultivated all year using present production methods. Tomatoes are produced for either manufacturing tomato paste, tomato pulp, tomato sauce, and ketchup or consumed as fresh fruit. However, excessive moisture levels in tomatoes generally result in increased water activity that promotes quality degradation and increases enzymatic activity, which leads to microbial growth. Therefore, the spray drying method is used to produce dried food powder, which may reduce postharvest losses while adding value to the raw product. The purpose of the paper is to review scientific research on the influence of carrier agents and operational parameters of spray-drying fruit extracts on physicochemical qualities such as moisture content, hygroscopicity, solubility, bulk density, water activity, and color difference. The current paper reviews the various formulation and process factors that impact the physicochemical characteristics of tomato powder microparticles produced by spray drying in order to find the optimum parameters to produce tomato powders with a high and effective product yield with improved powder qualities.
Electrochemical Behaviour of Silica Deposited on Stainless Steel by Electrophoretic Deposition Ni Made Intan Putri Suari; Delyana Ratnasari; Sahara Tulaini; W. Widiyastuti; Heru Setyawan
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.72638

Abstract

The purpose of this paper is to evaluate the characteristics of corrosion protection of stainless steel substrates coated with silica by electrophoresis with pulsed direct current (PDC) and constant direct current (CDC) with anodization. Electrophoresis was carried out using silica sol from sodium silicate solution as an electrolyte solution. Stainless steel functioned as an anode and carbon as a cathode with a constant electrode distance of 2 cm. The amplitude, duty cycle, and anodization effect on stainless steel corrosion protection characteristics were evaluated. The samples were characterized by linear polarization and electrochemical impedance spectroscopy (EIS) to see the characteristics of metal corrosion protection and scanning electron microscopy (SEM) analysis to see the morphology of the coating. This study showed that PDC electrophoresis and CDC accompanied by anodization could obtain silica film with good corrosion protection characteristics (high pore resistance and low admittance). Linear polarization results showed that metal corrosion protection behavior was increased by anodization. Similar results were obtained by EIS analysis which showed that pore resistance increased by anodization. The highest pore resistance obtained by the constant current with anodization is 543 ohms, and the lowest admittance is 0.0217. Corrosion protection characteristics are also influenced by the amplitude and duty cycle during electrophoresis. Silica film with a high pore resistance and a low admittance were obtained at a frequency, amplitude, and duty cycle of 80 Hz, 0.5 volts, and 60%, respectively. The silica film produced by pulsed electrophoresis resulted in better coating characteristics than by constant current with anodization, which is seen from the pore resistance value and its admittance.
Effects of Nucleation and Crystal Growth Rates on Crystal Size Distribution for Seeded Batch Potash Alum Crystallization Process Siti Zubaidah Adnan; Noor Asma Fazli Abdul Samad
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.74121

Abstract

The driving force of the cooling crystallization process is supersaturation, where the supersaturation level during the crystallization process is crucial to grow the crystal sufficiently. Nucleation and crystal growth rates are two concurrent phenomena occurring during crystallization. Both are supersaturation functions that determine the growth of seed crystals and the formation of fine crystals. Trade-offs between nucleation and crystal growth are essential for achieving the large size of seed crystals with the minimum number of fine crystals. Thus, the objective of this study is to analyze the effects of nucleation and crystal growth rates on final product quality, which is crystal size distribution (CSD). Modeling of the crystallization process using a potash alum case study is highlighted and simulated using Matlab software. Then, the effects of nucleation rate, crystal growth rate, and both nucleation and crystal growth rates on CSD are evaluated using local sensitivity analysis based on the one-factor-at-a-time (OFAT) method. Based on simulation results for all strategies, a low combined rate delivers the best performance of the final CSD compared to others. Its primary peak has a mean crystal size of 455 µm with 0.0078 m3/m volume distribution. This means that the grown seed crystals are large with high volume distribution compared to the nominal strategy, which is at the mean crystal size of 415 µm and 0.00434 m3/m. Meanwhile, the secondary peak has the mean crystal size of 65 µm, 0.00028 m3/m in volume distribution. This corroborates the least number of fine crystals at the considerably small size compared to nominal’s (0.00151 m3/m, 35 µm). Overall, the low nucleation and crystal growth rates strategy provides useful insights into designing temperature profiles during the linear cooling crystallization process, whereby achievable supersaturation levels in obtaining large crystals with fewer crystal fines are provided via simulation.
Comparison of Maseration and Sonication Method on Flavonoid Extraction from Mango Leaves: Effect of Solvent Ratio Alifiana Permata Sari; Nur Layli Amanah; Awalia Wardatullathifah; Agung Nugroho
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.74204

Abstract

Mango leaf extract has proven to contain flavonoids that serve as antioxidants. In this study, a comparison between traditional maceration and sonication on flavonoid extraction from mango leaf was investigated. The various ratios of ethanol and acetone were utilized as solvents (1:5, 1:10, and 1:15). The sonication process, which uses an ultrasonic cleaning bath set at 40 oC, takes 30 minutes as contrasted to the maceration procedure of 36 hours treatment at room temperature. The flavonoid test using aluminum (III) chloride (AlCl3) colorimetric technique shows that acetone provides greater solvent power than ethanol. According to this study, the optimal ratios for the maceration and sonication procedures are 1:10 and 1:15, respectively. The maceration process resulted in the optimum extract of 0.186 mgQE/g dry leaves. Meanwhile, using a 1:15 acetone solvent ratio and the sonication method, the highest concentration of flavonoid components was discovered, reaching 0.143 mgQE/g dry material with 54 times shorter time.
A Comparative Study on The Electrochemical Properties of Hydrothermal and Solid-State Methods in The NCM Synthesis for Lithium Ion Battery Application Sylvia Ayu Pradanawati; Eduardus Budi Nursanto; Afif Thufail; Ahmad Zaky Raihan; Sugianto Sugianto; Haryo Satriya Oktaviano; Hanida Nilasary; Achmad Subhan; Agung Nugroho
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.74209

Abstract

In this article, we report and compare the synthesis method of the active cathode materials based on nickel‐cobalt‐manganese (NCM) for lithium-ion battery application. We evaluate the hydrothermal and solid-state reaction method in NCM-622 synthesis, the material characterizations, and the battery performance. Based on the analytical results using X-ray diffraction (XRD), particles synthesized using hydrothermal and solid-state methods exhibit a highly crystalline NCM phase. NCM particles synthesized using solid-state reaction exhibit high-rate performance up to 10 C. The electrochemical impedance spectroscopy analysis shows that the charge transfer resistance (Rct) of NCM synthesized by the solid-state reaction (SSR) method was 25.9% lower than hydrothermal. Meanwhile, the ionic diffusivity of the SSR sample was 38.5% higher than the hydrothermal sample. These two factors lead to better performance when tested in a lithium-ion battery.
Application of Refuse-Derived Fuel (RDF) Plant in Piyungan Landfill Municipal Solid Waste Management Diananto Prihandoko; Chandra Wahyu Purnomo; Primanda Kiky Widyaputra; Nasirudin Nasirudin
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.75560

Abstract

Piyungan Landfill is the biggest landfill in the Yogyakarta Province that still operates in overcapacity condition. A new alternative is highly required in solid waste management in the landfill, which can reduce the volume of the waste coming into it and decrease the need for a new landfill area. Refused-derived fuel (RDF) plant is one of the technological alternatives in solid waste management that has the potential to reduce the volume of solid waste and change the waste into fuel. The study analyzed the potential of the application of the RDF to reduce the volume of solid waste in the Piyungan landfill and its economic feasibility. The results of the analysis showed that during the operational period of the RDF plant, the volume of the solid waste coming into the landfill could be annually reduced by 43% on average. The results of the economic analysis show that the RDF plant in the Piyungan Landfill is feasible to apply with an NPV of IDR 281.46 billion, an IRR of 24%, and a payback period of 6 years.
Development of Cavity Matrix Combustor for Biogas Application Young Nam Chun; June An
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.76154

Abstract

The use of conventional fossil fuels has limitations in energy resources and environmental problems such as greenhouse gas, air pollution, etc. Biogas has sustainable and renewable characteristics that can be used as an alternative energy source to alleviate these problems. In this study, we proposed a novel cavity matrix combustor that directly enables the combustion of what is produced in small and medium-sized biogas facilities without separation or purification. We also identified combustion characteristics for changes in air ratio, gas feed rate, biogas ratio, and exhaust gas recirculation rate and proposed optimal operating conditions based on this. The performance test result showed that the cavity matrix combustor is excellent for biogas combustion. The optimal operating conditions for the combustor are: the biogas ratio is 60% of CH4 and 40% of CO2, the air ratio is 1.1, the gas feed rate is 30L/min, and the exhaust gas recirculation rate is 100%. At this time, the combustion efficiency was 87%, and the unburned components were CO, UHCs, which are 0.01% and 0.05%, respectively, and NOx was 1ppm.
The Effect of Power on Nitrate Synthesis and The Emission Intensities of Reactive Species Using Anodic Plasma Electrolysis Harianingsih Harianingsih; Nelson Saksono; Eva Fathul Karamah; Zainal Zakaria
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.76790

Abstract

Nitrates are used as fertilizer to fulfill nutrients for plants. Anodic plasma electrolysis technology can be an effective and environmentally friendly solution in nitrogen fixation into nitrate compounds. This research aimed to determine the effect of controlling voltage and power in nitrate synthesis using plasma electrolysis with air as the raw material injected at the anode. The material used is an electrolyte solution of 0.02 M K2SO4, the electrodes used are in the form of tungsten and stainless steel, and a nitrate reagent is used for the nitrate test. The results of the study showed that at 400 W, the optimal rate was 0.8 L men-1 with 1889 mg L-1 of nitrate formed. While at 500 W and 600 W, the optimal rate of 1 L men-1 with nitrate formed was 2213 mg L-1 and 2453 mg L-1. The emission intensities of reactive species N, N2*, N2+,•OH, •H, and •O at an optimal rate of 0.8 L men-1 400 W 700 V in 20139 au, 28540 au, 18023 au, 30863 au, 12547 au, 49800 au. The addition of air injection will increase the oxygen input into the plasma zone, which can produce reactive species •O and nitrogen produces reactive species N, N2*, N2+ forms NO. The formed NO compounds can be oxidized to NO2, and the reaction between NO2 and reactive species •OH forms nitrates. 
Characteristics of Rapid Visco Analyzer Carrageenan Extract with Enzymatic Pretreatment of Kappaphycus striatum Hendrawan Laksono; Citra Kusumaning Dyah; Renny Primasari Gustia Putri; Maya Soraya; Heri Purwoto
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.76994

Abstract

Carrageenan is a polysaccharide compound extracted from red seaweed and is widely used by food, cosmetic, and advanced materials industries because of its good properties as an environmentally friendly stabilizer. Carrageenan extraction generally uses alkaline treatment for one full day, where the treatment is to obtain carrageenan quality with good gel characteristics. The use of cellulase enzymes is thought to accelerate the desulfuration process of seaweed, where cellulase enzymes are used to break down cellulose in seaweed cell walls. By using a rapid visco analyzer (RVA), carrageenan was tested to see the pattern and viscosity value. This study aims to determine the effect of enzymatic pretreatment on the profile of carrageenan with a shorter alkalization process compared to the alkalization commonly used by the industry. The results showed that enzymatic treatment before KOH alkalization would produce a carrageenan profile with a viscosity value of 272-360 cP, whereas the NaOH alkalization only reached 19-24 cP. The results of the test using RVA showed that the addition of an enzymatic process could change the physicochemical properties, such as viscosity and gel point of the carrageenan alkalinized with KOH. However, there was no significant difference in the properties when treated by alkalization using NaOH, which can be described from the value of the gelling point of carrageenan treated by cellulose enzyme. Adding enzymes to KOH will accelerate the gelation process, which occurs at an average temperature of 42.78oC. Meanwhile, carrageenan without enzymatic addition has an average gelation value of 37.48oC.
Characterization of Cellulose Acetate Membrane at Different Thicknesses on Sucrose Concentration by Forward Osmosis Aida I. Mohamad Idris; Siti Mazlina Mustapa Kamal; Alifdalino Sulaiman; Rozita Omar; Munira Mohammad
ASEAN Journal of Chemical Engineering Vol 22, No 2 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.77350

Abstract

Forward osmosis (FO) requires a specific membrane structure for applications like juice concentration. The phase inversion method was used to make cellulose acetate (CA) FO membranes. The solvents used were acetone and 1,4-dioxane. Additives included polyvinylpyrrolidone (PVP), methanol, and maleic acid were used in the preparation of CA membrane, which make it easier to improve a FO membrane's permeability. The performance of fabricated FO membrane and their  morphology were evaluaed with different casting thicknesses of 150, 200, and 250 µm. Experiment works begins with an hour of membrane flux testing, deionized water was used as feed solution and 1 M NaCl as draw solution. The membrane was then used to concentrate 0.5 M sucrose with NaCl for 240 minutes (2 M). Contact angle, porosity, and scanning electron miscroscopy (SEM) were used to characterize membrane properties and morphology. High water flux (2.25 L/m2hr) and high porosity (75.86%) were found at 200 µm casting thickness. Water permeability of sucrose concentration at 200 µm casting thickness had the highest flux (2.39 L/m2hr). The results also show that flux values vary with membrane thickness. All membranes were hydrophilic with contact angles below 90°.  A 200 µm casting thickness produces a membrane with smooth and evenly distributed pores, according to morphology analysis. Structural parameter (S) values had a proportional relationship with the FO membrane thickness, which thinner membrane potentially reduces the internal concentration polarization (ICP).

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