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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 372 Documents

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Co-solvent Selection for Supercritical Fluid Extraction of Essential Oil and Bioactive Compounds from Polygonum minus Masturah Markom; Norsyamimi Hassim; Nurina Anuar; Syarul Nataqain Baharum
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

This study evaluated the biological activity (antioxidant assay) of Polygonum minus extracted using Supercritical Fluid Extraction (SFE) added with different types of co-solvents. The seven co-solvents employed were water, methanol, ethanol, 50% methanol, 50% ethanol, 70% methanol and 70% ethanol for selection of the best co-solvent prior to optimization of SFE. 70% methanol produced the highest total yield of extract (33.1%) compared to other co-solvents. The antioxidant capacity was then evaluated using four different assays: the total phenolic content (TP), the total flavonoid content (TF), the ferric reducing/antioxidant power (FRAP) and the free radical-scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). The highest TP and TF were from 70% methanol extract (11.2 ± 0.15 mg GAE/g sample (mg GAE/g) and 11.9 ± 0.03 mg CAE/g sample (mg CEQ/g) respectively). 70% metanol extract also showed the highest FRAP value (346.7 ± 0.66 µmol Fe (II)/g sample) and the highest percentage of DPPH radical inhibition was also shown by 70% methanol extract (88.7 ± 0.40%). There was a positive correlation between the antioxidant capacity (FRAP and DPPH) with those of TP and TF contents. Therefore, the best co-solvent chosen for further optimization of SFE is 70% methanol.

Effects of Fluxing Agents on Filter Aids Prepared from Lam-Dong Diatomate Mai Thanh Phong; Tran Duy Hai; Phan Dinh Tuan
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Diatomite (or kieselguhr) is deposit of skeletal remains of single-cell water plants (diatom algae). Diatomite can be used as raw materials for production of several products, such as filter aids, fire-bricks, adsorbents, etc. Two major deposits of diatomite in Vietnam are in Phu-Yen and Lam-Dong province. This study aims to study preparation of filter aids from Lam-Dong diatomite. Especially, the study focused on investigating effects of fluxing agents on quality of filter aids. Physic-chemical properties of the filter aids were determined by using X-ray fluorescence spectrometer, scanning electron microscope and instrumentally measured color coordinates. Results of beer filtration were also presented in this paper. The obtained results proved that Lam-Dong diatomite can be used to manufacture standard filter aids for beer filtration.

A Dynamic Model for Ultrasonic – assisted Extraction of Bio-active Compounds from Natural Products Trung Kien Tran; Lan Huong Phung; Hoai Nga Le; Thi Thu Huyen Nguyen; Xuan Son Nghiem; Van Thiem Pham
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Ultrasonic technique has been applied for extraction processes, especially for separation of bio-active substances from natural organic products because of the short time requirement, energy saving and easy operating. The ultrasonic-assisted extraction (UE) therefore becomes a promising option. However, a major available obstacle was the lack of appropriate models for designing technological process. This paper presents a dynamic model for the UE process, application of separation of bio-active substances from natural products such as Curcumin from rhizome of Curcuma Longa L., Epigallocatechin from green tea leaf of Camellia Sinensis and Rutin from bud of Sophora Japonica. The agreement between data from experiment and calculated ones with the model indicates that, this dynamic model is suitable for prediction of the UE process and for serving as the base for further investigation into scale-up the extraction process.

Research on Biological Activity of some Extracts from Vietnamese Carica papaya Leaves Do Thi Hoa Vien; Phung Thi Thuy
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Carica papaya leaves have long been used in some folk remedies to treat cancer. This folk remedy originated from Queensland - Australia from 1978 (Harald W. Tietze, 1997). In Vietnam, there are some successful cases of using Carica papaya leaves for cancer treatment even though this mediation do not always work out. In this study, the soluble substances in water (aqueous extract), the carotenoid and the polar substances (polar extract) were extracted from Carica papaya leaves grown in Vietnam; the bioassays such as cytotoxicity on some tumor cell lines as well as antioxidant activity were also tested with obtained extracts. The results showed that all obtained extracts had antioxidant activity stronger than the control substance - vitamin C at the same tested concentration. At concentration of 100 μg/ml, the inhibitive activity on lung cancer cell line LU-1 of obtained extracts was highest, from 43.47% (aqueous extract) to 62.88% (polar extract). On carcinoma cell line KB, inhibitive ability of extracts was lower: 2.8% (polar extract) and 20.6% (aqueous extract). On the breast cancer cells MCF7, inhibitive ability of above extracts was quite high, from 33.95% to 56.19%. On the leukemia cell line HL 60, inhibitive ability of these extracts was also high, from 39.56 to 60.64%. In addition, the result pointed out that on stem cells isolated from mouse embryos (ESC), the obtained extracts was not toxic to healthy cells of this line. This suggested that extracts from Carica papaya leaves has the potential to become one of the natural substance products that can support cancer treatment in certain cases.

Optimization Research into the Ultrasonic-assisted Extraction to Separate Polyphenol from Green Tea Waste Lan Huong Phung; Trung Kien Tran; The Cuong Nguyen; Hong Quang Do; Thu Tra Phan; Hong Son Vu; Tien Huy Nguyen
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Today, green tea leaves (Camellia sinensis) have been grown in nearly 30 provinces in Vietnam. Catechins, which are polyphenols, are abundant in green tea. In a freshly picked tea leaf, polyphenols can compose up to 30% of the dry weight. Recently, researchs have focused on tea polyphenols due to its potent anti-oxidant activity, anti-inflammatory and anti-cancer effects. Viet Nam currently ranks the fifth in the world in tea production and export turn-over. However, green tea is made from the top two leaves and buds of a shrub. A large amount of stems, older leaves and tea wastes from tea factories is not produced. For this reason, study to separation polyphenols from these materials plays an important role in science, society and economy. Polyphenols can be extracted from green tea leaves by using hot water and organic solvents. In the method of using hot water, green tea quality deteriorates and catechins are destroyed due to the heat applied. Therefore, we attempted to increase the amount of polyphenols in extracts with using ultrasonic irradiation at low temperature. This work has an aim to investigate the influent process parameters such as extraction time, stirring speed and the rate of raw material/solvent on efficiency of the extraction of polyphenols and antioxidant properties obtained extracts. The ultrasonic-assisted extraction was conducted at room temperature, ultrasound frequency (25 kHz) using water solvent. Extracts were analysed for total phenols content (TPC) by the Lowenthal method. The antioxidant properties have been determined by DPPH free radical scavenging effect, The results of the work are the basis to determine of the optimal technological factors by employing desirability methodology with experimental order of Box-Behnken design and to scale up for designed industrial extraction system that can be applied in tea plants for the production of tea polyphenols from tea wastes.

Optimisation of LS54/Dx Aqueous Two Phase System Conditions for Cutinase Recovery Jamaliah Md. Jahim; Abdul Wahab Mohamad; Fariza Akmal Abdul Mutalib; Farah Diba Abu Bakar; Osman Hassan
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Aqueous two phase system comprising Dehypon® LS 54 and K4484 Dextrin® was selected for recovery of cutinase enzyme. Parameters such as pH, system composition and type of salt as an additive, influenced the protein partitioning behaviour and optimisation of these parameters become necessary to be done in the design of primary recovery process of ATPS. The cutinase partitioning experiments were carried out with 30% of cutinase solution added to LS 54/Dx system. Results showed that cutinase enzyme preferred to partition into LS 54 rich-phase at pH 8.0 and the affinity of cutinase into top phase was observed higher with the increment of system compositions, which represented by tie line length (TLL). Furthermore, the addition of 50mM salts such as K2SO4 and KCl into LS 54/Dx system has led to raise partition coefficient of cutinase, kcut to 2.2 and 1.95 fold, respectively. The dependence of kcut on various additives such as (NH4)2SO4, Na2SO4 and K2SO4 at the same concentration, suggested that the addition of selected ions could enhance positive electrostatic potential which could attract more cutinase to partition into LS54 rich phase. As conclusion, the best conditions obtained for cutinase partitioning were pH8.0, TLL = 23% and Na2SO4 = 50mM, from which the maximum kcut of 2.83 with improved recovery of cutinase in top phase up to 79% can be achieved.

Characteristics of Flame Shapes and Map For LPG and Hydrogen Inverse Confined Diffusion Flames at High Level of Fuel Excess Yazid Bindar; Anton Irawan
ASEAN Journal of Chemical Engineering Vol 12, No 1 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

A combustion flame can be generated by locating the air jet supply inside the fuel jet supply. This flame is referred as an inverse diffusion flame. The size and structure of inverse diffusion flame were studied experimentally. The experiment was conducted for LPG and Hydrogen fuels. The inlet fuel and air flow rates are supplied at high level of fuel excess for its combustion reaction. These two fuels generated the flame shape having two parts. At lower part, the flame is wider and serves as a base of the flame. The upper part is longer and acts as a flame tower. The base flame was a weak flame resulted by a rich fuel-air mixture. The tower flame is formed by mixing between the entrained fuel and the air. The flame length decreases with the increase on the momentum ration between fuel and air. The flame height correlates to the fuel and air Reynold number ratio, Refu/Rea. The development of the flame shapes from continues to strong base-tower flame shape is mapped by air and fuel inlet momentum rate. Very low fuel and air momentum rates result laminar flame and continuous shapes. The turbulent flames having base-tower shape are formed at high air momentum rate. The oxygen profiles shows that the oxygen concentration decays from the burner tip, vanishes at some distance from the burner tip and increase again after this distance. The hydrogen is completely consumed before the flame tip is reached

Microstructural Dependency of Diffusion in Glass Flake-Reinforced Vinyl Ester Resins Bryan B. Pajarito; Masatoshi Kubouchi; Hiroyuki Tomita; Saiko Aoki
ASEAN Journal of Chemical Engineering Vol 12, No 1 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Vinyl ester resins are utilized for long-term corrosion protection of metal, alloy, and concrete substrates against concentrated acids, alkalis, and solvents at high temperature. Glass flakes are usually added as fillers to reduce chemical diffusion within the vinyl ester matrix. A common industry practice is to use glass flakes with large aspect ratio, high volume fraction, and in parallel alignment to surface in chemical contact for barrier applications. During processing and curing of glass flake-filled vinyl ester resins, irregular microstructures such as reduced flake aspect ratio and random orientation of flakes are commonly observed. Such microstructures can affect the overall chemical diffusion, resulting to barrier properties less predictable by simple diffusion models. Therefore, in this study, a simple 2D random walk simulation procedure is used in attempt to estimate the microstructural dependency of diffusion in glass flake-reinforced vinyl ester resins. While the random walk simulations are in good agreement with the tortuosity-based diffusion models in terms of microstructural effects, in most cases the simulation results are inconsistent with the experimental measurements of acid diffusion in glass flake-filled vinyl ester resins. A possible cause for this is the poor adherence of vinyl ester resin to glass flakes. Osmotic cracks are also formed during immersion which also influences overall diffusion through the material.

Synthesis of Ternary Homogeneous Azeotropic Distillation Sequences: Entrainer Selection Sutijan Sutijan; Megan Jobson; Robin Smith
ASEAN Journal of Chemical Engineering Vol 12, No 1 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

This paper presents a methodology for automatic selection of entrainers for separating binary azeotropic mixtures using homogeneous azeotropic distillation. A new classification system for ternary mixtures based on the termini of distillation boundaries and the type (stability) of products and azeotropes is proposed. The new characterisation system is able to link candidate entrainers to flowsheet structures which can facilitate the separation. Existing entrainer selection criteria are extended to accommodate other promising entrainers, including light, intermediate and heavy-boiling entrainers.

Characterization and Photocatalytic Activity of Nano-TiO2 Doped with Iron and Niobium for Turquoise Blue Dye Removal Nhat Minh Doan; Carl Renan Estrellan; Anton Purnomo; Susan Gallardo; Chris Salim; Hirofumi Hinode
ASEAN Journal of Chemical Engineering Vol 12, No 1 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

The nano-TiO2 photocatalysts doped with Iron and Niobium for dye wastewater treatment were prepared by temperature-controlled sol-gel method. The effects of these dopants on the physical and chemical properties of TiO2 were compared with the commercially available Degussa TiO2 P25. Among these characteristics are crystalline size, the presence of absolute anatase phase, band gap energy and specific surface area. The characterization data were correlated to photocatalytic activities using Turquoise blue dye (TBD) as model pollutant. Single doping (with Nb) and co-doping (Fe and Nb) catalyst reached complete decolorization within 2.5 hours and 3 hours. In addition, their kinetic reaction rate constants of apparent first-order model are 0.0258 min-1 and 0.0225 min-1, respectively. The presence of Nb as traps is considered to play a crucial key in enhancing the photocatalytic activity.

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Ari Pramudyantoro

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ajche.ft@ugm.ac.id

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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

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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