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ASEAN Journal of Chemical Engineering

AJChE
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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 8 Documents

Search results for , issue "Vol 19, No 2 (2019)" : 8 Documents clear

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

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

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.

Influence of Ethanol Concentration and Template Ion Exchange Agent on Template Recycling in Mobil Crystalline Material 41 (MCM-41) Synthesis Jia Yen Lai; Lock Hei Ngu; Farouq Twaiq
ASEAN Journal of Chemical Engineering Vol 19, No 2 (2019)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Recycling of surfactant template for several subsequent MCM-41 synthesis is necessary to reduce substantial synthesis solution disposal. In MCM-41 synthesis, ethanol concentration and template ion exchange agent are two significant factors that affect the silicate polymerization, solvating effect on micelles formation, and MCM-41 mesostructure formation. In view of that, this study investigates recycling of surfactant template ions in extract solution in Mobil Crystalline Material 41 (MCM-41) synthesis. Effect of the ethanol concentrations in the solution gel and the types of ion exchange agents on the yield of MCM-41 material and its surface morphology were studied. Hexadecyltrimethylammonium bromide was used as template for MCM-41 synthesis using tetraethylorthosilicate (TEOS) as silica reagent with ethanol-water mixture as solvent at different ethanol concentrations. Template ions of synthesis gel was exchanged with an ion exchange agent (i.e., 1-butyl-3-methylimidazolium chloride or ammonium nitrate) before it is extracted using synthesis solution. After extraction, the extracting solution was added with TEOS, used for second synthesis cycle and the process continued in an extraction. The template ions in the extract solution were further recycled up to eight synthesis cycles. Yield of calcined materials significantly influenced by ethanol solvent concentrations and however did not vary with various ion exchange agents. Nitrogen adsorption isotherms showed that the calcined materials exhibit MCM-41 characteristics with surface areas ranging from 600 – 1000 m2/g. It is possible to recycle and reuse the surfactant template for several subsequent times of preparing MCM-41 if the ethanol concentration in the solution gel controlled continuously.

Statistical Approaching for Superhydrophobic Coating Preparation using Silica Derived from Geothermal Solid Waste S Silviana; Adi Darmawan; Agus Subagio; Febio Dalanta
ASEAN Journal of Chemical Engineering Vol 19, No 2 (2019)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Material quality can be affected by humidity resulting in short durability. Many observations have been conducted to endure the durability of material, such as coating methods. However, recent methods are unaffordable. Therefore, this paper observes efficient and effective method to prepare superhydrophobic silica coatings derived from geothermal waste. The method was conducted by spraying. The objective of this paper is to observe optimum condition by using variables of silica concentration, TMCS (trimethylsilyl chloride) concentration, solvents and materials confirmed by contact angle of material based on statistical analysis. The study consisted of silica treatment for purification and preparation of superhydrophobic silica coatings. The study was carried out in factorial design of 81 experiments with one-time replication through Design Expert software (version 8.0.6). Based on previous research, the experiment was obtained optimum condition at 5.5 %w/v, 13 %v/v, isooctane, zinc coated for silica concentration, TMCS concentration, solvent and material, respectively, releasing contact angle by instrumentation of 180°. By ANOVA analysis, it was also complied the optimum condition of the superhydrophobic coating solution preparation achieved the same condition with experimental data releasing contact angle of 179.69°.

Composite of Kaolin/Sodium Alginate (SA) Beads for Methylene Blue Adsorption Irwin Tan Kai Ge; Muhammad Wahyu Nugraha; Norashikin Ahmad Kamal; Nonni Soraya Sambudi
ASEAN Journal of Chemical Engineering Vol 19, No 2 (2019)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Dyeing industry is one of the fast-growing industries but at the same time has also brought us a big issue on environment pollution. Adsorption processes is the most effective method in dye removal compared to other methods of wastewater treatment. In recent years, there is an increasing interest in utilizing clay material such as kaolinite as an adsorbent to remove not only inorganic but also organic molecules. In this study, composite of kaolin-sodium alginate (SA) beads was synthesized by varying the weight of kaolin from 0.5 g to 2 g. XRD, FTIR, and surface area analyses were used to characterize the kaolin; while FTIR was used to characterize the composite where the functional groups of kaolin and SA are existing. The amount of 1 g kaolin in SA could improve the adsorption of methylene blue up to 78% of removal after 8 hours. The adsorption model fits pseudo second order kinetic and Langmuir isotherm

Amine-based Carbon Dioxide Absorption: The Ionic Strength Effect on the Monoethanolamine Protonation Constant at Temperatures from 313 to 333K Sholeh Ma'mun; Panji Kumala Setiawan; Egip Indrayanto
ASEAN Journal of Chemical Engineering Vol 19, No 2 (2019)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Amine-based absorption has been extensively used for carbon dioxide (CO2) removal processes, such as CO2 absorption from flue gas as well as from natural gas. As a reactive system in which the chemical reaction, as well as mass transfer, occur simultaneously, an experimental determination of equilibrium reaction constants, e.g. acid dissociation/protonation constant (Ka), is, therefore, necessary to be conducted. This study aims to evaluate the ionic strength effect from 0.06 to 6.0 m (mol/kg water) on the Ka value of monoethanolamine (MEA) at temperatures between 313 and 333K. The experimental results indicate that the pKa values tend to be increasing as the ionic strength increases. This is contradicting to the temperature effect where the pKa values tend to be decreasing as the temperature increases. Furthermore, the extended Debye-Hückel formulation was implemented to predict the species activity coefficients.

Effect of Gasification Temperature on Synthesis Gas Production and Gasification Performance for Raw and Torrefied Palm Mesocarp Fibre Najwa Hayati Abdul Halim; Suriyati Saleh; Noor Asma Fazli Abdul Samad
ASEAN Journal of Chemical Engineering Vol 19, No 2 (2019)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Biomass gasification is widely used for converting solid biomass into synthesis gas for energy applications. Raw biomass is commonly used as feedstock for the gasification process but it usually contains high moisture content and low energy value which lowering synthesis gas production. Thus, torrefaction as a pre-treatment process is necessary in order to upgrade the properties of feedstock for producing more synthesis gas production and improving gasification performance. The objective of this work is to study the effect of gasification temperature on the synthesis gas production and gasification performance using raw and torrefied palm mesocarp fibre (PMF). The gasification process is conducted using bubbling fluidized bed using steam as gasifying agent. Based on experimental work, by increasing gasification temperature from 650 – 900 °C, the compositions of hydrogen and carbon monoxide gases were enhanced greatly while carbon dioxide and methane gases were decreased for both raw and torrefied PMF. In terms of gasification performance, synthesis gas yield for raw and torrefied PMF is increased from 0.91 to 1.23 Nm3/kg and 1.10 to 1.35 Nm3/kg respectively. Besides, lower heating value (LHV) of torrefied PMF is 0.04 MJ/Nm3 higher than raw PMF at 900 °C. The result showed that the percentage of cold gas efficiency (CGE) reached maximum of 67% for raw PMF while carbon conversion (CC) at 85.6% for torrefied PMF at a gasification temperature of 900 °C. The higher CC obtained by torrefied PMF is because of the increment of carbon content from 45.2% to 53.7% as a result of torrefaction. Gasification temperature of 800 °C showed the best performance of the PMF gasification since the maximum performances of LHV is achieved and started to decrease once the gasification temperature is operated beyond 800 °C.

Microparticles Formation of Ganoderma lucidum Extract by Electrospraying Method Siti Machmudah; Dwi Setyorini; Sugeng Winardi; Wahyudiono Wahyudiono; Hideki Kanda
ASEAN Journal of Chemical Engineering Vol 19, No 2 (2019)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

In this work, Ganoderma lucidum (G. lucidum) extract was produced in microparticles form by electrospraying. G. lucidum was extracted hydrothermally at temperature of 160oC and pressure of 7 MPa. The extract solution was subsequently mixed with 6% of Polyvinyl pyrrolidone (PVP) and formed into microparticles by electrospraying process. The electrospraying was carried out at applied voltage of 12, 14, and 16 kV, and the distance between syringe tip and electrospun collector of 8, 10, and 12 cm. The microparticles formed was analyzed using scanning electron microscope (SEM), fourier-transform infrared (FTIR) spectroscopy, and UV-Vis spectrofotometer. The antioxidant efficiency of particles was also analyzed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Based on the SEM analysis, the G. lucidum extract (GLE) – PVP spherical particles were formed by electrospraying. The finer fibres were clearly formed with the increasing applied voltage. The results showed that applied voltage and distance of tip to electrospun collector significantly influence the antioxidant efficiency and the diameter size of particles. The antioxidant efficiency increased with the rising applied voltage and gap of tip to electrospun collector, while the particle diameter decreased with the rising applied voltage and gap of tip to electrospun collector due to fast mass transfer and evaporation. The largest antioxidant efficiency of particles was 0.377/min obtained at 16 kV and 12 cm. It indicated that electrospraying is an effective process to produce pharmaceutical compounds in powder form.

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Ari Pramudyantoro

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+62274555320

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Jln. Grafika No. 2 Kampus UGM Yogyakarta Indonesia 55281

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Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

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

Abstract

Abstract

Abstract

Abstract

Abstract

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Abstract

Abstract

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