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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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Stepwise Methanolysis of Waste Cooking Oil Using Immobilized Thermomyces lanuginose Lipase within Ultrasonic-assisted Condition Nur Sabrina Abdul Manab; Harumi Veny; Azianna Gusniah; Sarina Sulaiman; Noorhaliza Aziz
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.60358

Abstract

Biodiesel or fatty acid methyl ester is a fuel derived from vegetable oil and animal fat. In this study, biodiesel is produced from transesterification of waste cooking oil and methanol (methanolysis), using immobilized Thermomyces lanuginose (TLIM) within ultrasonic-assisted conditions. The enzymatic transesterification is used due to environmental concerns and also the high yield of biodiesel. The limitations in the mass transfer rate of the product and longer reaction time have drawn attention to more efficient technology. One of them is ultrasonic-assisted to reduce reaction time and increase the catalytic activity of the enzyme. Various parameters have been examined in this study, such as reaction time, methanol to oil ratio, the effect of temperatures, and temperature dependency of immobilized Thermomyces lanuginose (TLIM). The highest biodiesel yield of 69.3% was obtained after 6 hours of reaction at a temperature of 35°C and using three step-wise addition of methanol to oil ratio 3:1. Our study showed that the TLIM is sensitive to methanol to oil molar ratio above 1:1. Further research on the temperature dependence found that the TLIM activation energy in the reaction is 11.9 kcal/mol, which is within activation energy for an enzymatic reaction.
Yield and Extraction Rate Analysis of Phytochemical Compounds from Eucheuma cottonii, Ganoderma lucidum, and Gracilaria sp. using Subcritical Water Extraction Fesa Putra Kristanto; Siti Machmudah; Sugeng Winardi; Wahyudiono Wahyudiono; Motonobu Goto
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.60513

Abstract

Eucheuma cottonii (E. cottonii), Ganoderma lucidum (G. lucidum), and Gracilaria sp. are plants that contain high phytochemicals, such as flavonoids, polyphenols, saponins, and tannins. In this work, the phytochemicals were obtained using the subcritical water extraction (SWE) process. The SWE method uses water as a solvent in subcritical conditions. Therefore, the SWE process is an environmentally friendly process for extraction. In order to run the SWE process optimally, measurement of the extraction rate of SWE is needed. Calculation of the extraction rate of SWE process used first and second-order models according to Lagergren equation. SWE process was started by setting temperatures from 140 to 180oC at a pressure of 7 MPa and solvent flow rate of 1 ml/min. Before starting the extraction, the raw material was loaded into the extractor. The raw materials used were E. cottonii, G. lucidum, and Gracilaria sp. The extraction process was carried out for 3 hours, and the product was collected every 30 minutes. The collected product was put into a sample bottle and dried using a freeze dryer. After that, the products obtained were balanced by an analytical scale. Based on the result, the optimum temperature for the SWE process was 180oC for E. cottonii and G. lucidum and 160oC for Gracilaria sp. The yields of the SWE process under the optimum temperature were 85.37%, 58.42%, and 75.73% for E. cottonii, G. lucidum, and Gracilaria sp, respectively. The extract contained phytochemical compounds detected by high-performance liquid chromatography analysis. The kinetics model of extraction rate for all variables exhibited a second-order kinetics model that indicated that the extraction process was influenced by more than one factor.
Generalized Pitzer Correlation for Density Calculations of Ionic Liquids Jesus Patrick Nuqui; Regina Damalerio; Sychheng Meas; Socheata Yem; Allan Soriano
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.60787

Abstract

The density of ionic liquids is an important design parameter for its utilization as a chemical process solvent. In this study, a generalized Pitzer-type correlation for calculating the density of ionic liquids with the use of reduced temperature (TR), reduced pressure (PR), and acentric factor (ω) as parameters is proposed. Experimental density data were obtained from several references through the IUPAC Ionic Liquids Database. Expansion of the terms as well as integrating the ionic liquid molecular weight was attempted to determine the accuracy improvement of the model in predicting densities at 0.1 MPa. Then, the obtained model was modified by further truncation to include the pressure effects for densities at higher pressures. MATLAB software was used to determine the optimal virial coefficients for the proposed correlations. The percent average absolute deviation (%AAD) was applied to calculate the variation between the experimental and calculated density values. It was concluded that the eight (8) coefficient correlation equation with molecular weight for densities at 0.1 MPa had a %AAD of 4.7537%. Upon modifying the correlation to include pressure effects, the resulting modified equation had an overall %AAD of 4.7174%.
Nanocellulose Production from Empty Palm Oil Fruit Bunches (EPOFB) Using Hydrolysis Followed by Freeze Drying Irwan Hidayatulloh; Emmanuela Maria Widyanti; Endang Kusumawati; Lidya Elizabeth
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.61093

Abstract

Empty palm oil fruit bunches (EPOFB) are lignocellulose which is abundantly available in Indonesia. EPOFB has big potential as raw materials to substitute wood in nanocellulose manufacture. The production of nanocellulose from EOPFB consists of various stages, such as preparation by grinding and sizing, α-cellulose isolation, acid hydrolysis, and freeze-drying. α-cellulose isolate from POEFB through delignification using 17.5% NaOH (w / v) at 80oC for 30 minutes and bleaching using 10% H2O2 (v / v) at 70oC for 15 minutes. The bleached cellulose was then hydrolyzed by acid hydrolysis process using 64% H2SO4 for 45 minutes with temperature variations to determine the effect of temperature on the size of nanocellulose. Obtained nanocellulose then dried with the freeze-drying method at a temperature of 50oC for 6 hours. The nanocellulose morphology was characterized using SEM analysis, and FTIR analysis was done to determine the presence of cellulose and lignin.  The smallest average diameter obtained at 50oC temperature is 86.8 nm with a 51.5 – 66.5 nm distribution range.
The Effect of Amino-functionalization on Photoluminescence Properties of Sugarcane Bagasse-derived Carbon Quantum Dots Muhammad Wahyu Nugraha; Nonni Soraya Sambudi; Laksmi Dewi Kasmiarno; Norashikin Ahmad Kamal
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.61234

Abstract

In the present study, amino-functionalized carbon quantum dots (N-CQDs) were prepared from sugarcane bagasse using a simple one-pot hydrothermal method. Both ethylenedinitrilotetraacetic (EDTA) & ethylenediamine (EDA) were used as carbon and amino sources, respectively. The emerging utilization of natural carbon precursors is critically essential considering its low cost, eco-friendly, and unexploited by-products (e.g., sugarcane bagasse), which may have sustainable economic and strategic benefits. The as-prepared N-CQDs were characterized using High-Resolution Transmission Electron Microscope (HRTEM), Fourier Transform Infrared Spectroscopy (FTIR), UV-vis absorption spectroscopy, and photoluminescence spectroscopy. The influences of amine groups were investigated. The as-prepared N-CQDs photoluminescence intensity increased and quenched significantly with EDTA and EDA amino-functionalization, respectively, with the highest quantum yield at 21.21%, 2.4 times higher than non-functionalized CQDs. Furthermore, the amino-functional groups can alter the CQDs structure and particle size ranging from 4.197±1.058 nm to 9.704±1.428 nm. Hence, the N-CQDs produced exhibit highly tunable photoluminescence and particle size potentially applicable in diverse applications.
Effect of nano-α-Al2O3 Particles on Mechanical Properties of Glass-Fibre Reinforced Epoxy Hybrid Composites Anil Kumar Veerapaneni; Chandrasekar Kuppan; Murthy Chavali
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.61250

Abstract

The present work deals with the mechanical properties of hybrid nanocomposites made of epoxy/glass fibre dispersed with different weight percentages of nano-α-Al2O3 powder . The nanoparticles were synthesized by a high energy ball milling technique (60 and 200 nm).. The effect of nano-α-Al2O3 size and content (wt%) on mechanical properties, such as tensile, flexural, interlaminar shear stress (ILSS) and hardness was investigated. The addition of nano-α-Al2O3 enhanced all measured mechanical parameters because of their higher surface area and interfacial polymer-metal interaction. The nanoparticle-embedded laminates showed an improvement in flexural strength and hardness compared to laminate without nano-α-Al2O3. Among all the wt% of varied sizes of nano-α-Al2O3, the highest tensile strength was shown by the addition of 0.5 wt% 200nm nano-α-Al2O3 (167.80 N/m2). The highest flexural strength (378.39 N/m2) Vickers hardness (86.72) were observed for laminates containing 1.5 wt% of 60nm nano-α-Al2O3, while the highest ILSS (31.21 Ksi) was observed for 0.5 wt% of 60nm nano-α-Al2O3. This study showed that there was a higher interaction between the nanoparticle and polymer resin, which led to increasing the mechanical properties of the laminate. This finding show that diversifiying the application of these hybrid materials was possible by adding nano-alumina.
Hydrothermal Treatment of Herb Residue for Solid Fuel Production Fredy Surahmanto; Didik Nurhadiyanto; Mujiyono Mujiyono; Chinnathan Areeprasert; Mochamad Syamsiro
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.62594

Abstract

Hydrothermal processing is appraised as one of  advanced technologies for wet solid waste handling. In this study, herb residue was subjected to hydrothermal treatment. Calorific value, yield, and also proximate analysis of obtained hydro-char were investigated. A cylindrical reactor with an internal volume of 2.5 Litres made of stainless steel and a low-tech component was used in the experiment. The reactor was equipped with a stirrer to ensure heat transfer took place through the entire parts of the solid-water mixture. Solid products were dried by a microwave oven before analysis. The results show that the final temperature, holding time, and solid-water ratio have various effects on the hydro-char yield, calorific value, and proximate analysis of the hydrothermal products. The hydro-char yield decreased with the increase in final temperature and holding time. Meanwhile, the highest hydro-char yield was obtained at the solid-water ratio of ¼. The hydro-char calorific value increased with the increase in final temperature, holding time, and solid-water ratio. The rise in final temperature, holding time, and solid-water ratio resulted in  a lower moisture content and volatile matter but higher fixed carbon. Meanwhile, the ash content increased with the solid-to-water ratio.
Drying Kinetics and Modelling of Convective Drying of Kedondong Fruit Cheak Theng Ee; Yee Jian Khaw; Ching Lik Hii; Choon Lai Chiang; Mohamad Djaeni
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.62932

Abstract

Kedondong is an underutilized fruit cultivated in a small scale in Malaysia and it contains nutrients that can be preserved through drying. The dried product can be sold as a premium fruit snack that could generate revenue for the producer. We studied the drying of peeled and unpeeled kedondong fruits using hot air (60-80°C). This study aims to investigate the drying kinetics (drying rates and effective diffusivities) of kedondong fruits and model the drying curves using thin layer models. Ten thin layer models were employed and solved using non-linear regression. Drying kinetics showed that only falling rate periods were observed, which implied that internal diffusion was the dominant mechanism for moisture release. Mathematical models showed that Modified Hii et al. (I) and (II) models were able to predict the drying curve well with the highest R2 (0.9992-0.9999), the lowest RMSE (8.0 x 10-4 - 2.5 x 10-3) and the lowest χ2 (4.0 ×10-5 - 2.0 x 10-4). Peeled  samples showed higher effective diffusivities (average 3.2 x 10-11 m2/s)  than unpeeled samples (average 2.7 x 10-11 m2/s). The activation energy was lower in peeled samples (25.8 kJ/mol) as moisture diffusion could occur more easily than unpeeled samples (32.1 kJ/mol). Results from this study provide kinetic information that can be used in scaling up of dryer and optimizing dryer performances.
The Effect of Reaction Time and Temperature on the Synthesis of Methyl Ester Sulfonate Surfactant from Palm Oil as a Feedstock using Microwave-Assisted Heating Lailatul Qadariyah; Sahiba Sahila; Mahfud Mahfud
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.63786

Abstract

Methyl ester sulfonate is an anionic surfactant that can be synthesized from palm oil as a raw material with the addition of sodium bisulfite and calcium oxide catalyst through transesterification and sulfonation process using microwave-assisted heating. The effect of microwave-assisted heating in the transesterification-sulfonation process was investigated in this study. The transesterification process was carried out using a microwave power of 300 watts for 10 minutes with an addition of a KOH catalyst of 1%. The transesterification process gave a result of palm oil methyl ester with a yield of up to 98% and density of 0.8546 gr/ml, and kinematic viscosity of 3.19 cSt. The sulfonation process is carried out using palm oil methyl ester and sodium bisulfite with a mole ratio of 1:3 and calcium oxide catalyst of 1.5% with the microwave power of 300 watts while varying the sulfonation time and temperature. The physicochemical properties of methyl ester sulfonate were analyzed, and the sulfonate group was characterized using FTIR. The optimum condition gave a yield of up to 98.68%, the density of 0.8657 gr/ml, viscosity of 3.75 cSt, pH of 2.12, and surface tension of up to 27.34 dyne/cm at a temperature of 100oC and sulfonation time of 40 minutes.
Appropriate Technology for Municipal Solid Waste Management Based on Wastepreneurship Implementation Diananto Prihandoko; Arief Budiman; Prabang Setyono; Chafid Fandeli; Maria Theresia Sri Budiastuti
ASEAN Journal of Chemical Engineering Vol 21, No 1 (2021)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.64496

Abstract

Piyungan landfill is the biggest landfill in the Special Region of Yogyakarta, Indonesia, which receives municipal solid waste (MSW) from two districts and a city, while its designed service time has been over and faces operational obstacles. Meanwhile, the volume of the MSW grows rapidly and exceeds the reduction rate in their sources. The difficulty in finding a new landfill area is the reason why appropriate technological alternatives in the MSW management are strongly needed. Therefore, the study aimed to evaluate the social and economic aspects and formulate appropriate technology based on the waste entrepreneurship (wastepreneurship) concept. The methods of this study were conducting calculation of waste characteristics and composition, social evaluation, and economic evaluation of the combination of composting, incinerator, and sanitary landfill. Waste characteristics and composition were taken using direct field measurement following Indonesia's National Standard Guideline about retrieving and measuring examples of urban waste emergence and composition. Characteristics of waste are used for the calculation of calorific value and energy. The social evaluation was conducted using an in-depth interview with the rag pickers. The economic evaluation was conducted using net present value, internal rate of return, and payback period. The result of the study shows that Piyungan Landfill with total combustion waste reach 82.22% has the potential of incinerator implementation. In social evaluation, the implementation of composting and incinerator technologies would open employment for the surrounding community and rag pickers. The economic evaluation shows the combination of composting and incinerator technologies was economically feasible with an average profit margin of 12.97% in the operational period of 18 years. In conclusion, the concept of wastepreneurship is relevant in Piyungan Landfill by adjusting the MSW management paradigm from previously cost-center into business-center.

Page 30 of 38 | Total Record : 372

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