Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

ASEAN Journal of Chemical Engineering

AJChE
Website

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 6 Documents

Search results for , issue "Vol 15, No 2 (2015)" : 6 Documents clear

Effect of Sintering Temperature on the Fabrication of Ceramic Hollow Fibre Membrane Syafikah H Paiman; Mukhlis A A Rahman; Mohd Hafiz Dzarfan Othman; Siti Halimah Ahmad
ASEAN Journal of Chemical Engineering Vol 15, No 2 (2015)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Recently, ceramic membrane gradually acquired attention from researchers due to the advantages of ceramic’s behavior, which allows the ceramic to overcome the limitations of using polymeric membrane. This work focused on the fabrication of ceramic hollow fibre membrane from a ceramic suspension solution containing yttria-stabilized zirconia (YSZ), polyethersulfone (PESf), N-methylpyrrolidone (NMP) and dispersants using combined phase inversion sintering technique. In this study, ceramic hollow membrane precursors were sintered at different sintering temperature ranging between 1250°C and 1400°C. The influences of sintering temperature on the microstructure, porosity and pore size distribution, mechanical strength and pure water flux of ceramic hollow fibre membrane were investigated in detail. The results show an asymmetric structure of YSZ hollow fibre membrane containing finger-like structure and sponge-like structure. The sponge-like structure can serve as a separation layer, while finger-like-structure performs as a supported layer. It is observed that sintering process caused a significant densification of sponge-like structure (microstructure). Sintering at temperature 1400°C shows the formation of non- interconnected voids. Sintering at 1300°C is sufficient enough having a mechanical strength of 227.55MPa with an apparent porosity of 45.09% and PWF of 118.39L.m¯².hr¯¹.

A Morphology Studies On Effect Of A Coagulation Bath Mediums As The Phase Inversion Parameter For Poly (Vinylidene Fluoride) (Pvdf) Membranes A.R. Nurul Izzati; M.D. Irfan Hatim; H Hasbullah; Adil Hatem Rashid
ASEAN Journal of Chemical Engineering Vol 15, No 2 (2015)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

In recent years there has been a considerable interest in modifying the PVDF membrane properties to suit with a wide range of applications. However, due to the multivariate nature in membrane fabrication steps, the fabrication techniques remain the key issue. In this article, the uses of different concentration of ethanol in the coagulation bath were investigated as it can improve the hydrophobicity of PVDF membrane and the membrane porous microstructure, i.e. finger-like microstructure. In addition, the coagulation mediums play an important role in determining extended of liquid-liquid demixing/crystallization via an immersion precipitation process. In this study, the effects of coagulation bath mediums on the morphology of PVDF membrane were investigated. Scanning electron microscope (SEM) was used to characterize the membrane microstructure. Octanol was used as a medium to estimate porosity of the membrane by determining the weight of liquid occupied within the membrane pores. The concentration of ethanol in the coagulation bath was varied at 0% until 75% with different evaporation time of 0 and 2 min. The SEM results indicate that the membrane surface porosity changes as ethanol concentration increases. Interestingly, at 0 to 25% ethanol, an asymmetric structure which consists of a dense skin layer accompanied by finger-like structure was formed during membrane casting. The more porous finger-like region which extends towards the skin layer is beneficial for membrane fuctionalization.

Comparison of Thermal Properties of PCB Photoresist Films Cured by Different Techniques Piyachat Wattanachai; Christian Antonio; Susan Roces
ASEAN Journal of Chemical Engineering Vol 15, No 2 (2015)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

The possibility of implementing microwave technology to photoresist film curing which is a major process in the production of electronic printed circuit boards (PCB) was investigated and compared with a conventional curing method, e.g. UV lithography. Since both techniques involved irradiation, hot plate curing which relies on thermal conduction was undertaken to study the effect of a heat transfer approach. Two film thicknesses were studied, i.e. 0.0012 and 0.002 inch, and the effects of curing power and time were investigated. Thermal properties, i.e. percent cure, glass transition temperature (Tg), composition and degradation temperature (Td), were evaluated using a Differential Scanning Calorimeter (DSC) and Thermogravimetric Analysis (TGA) and it was found that the commercial UV irradiation was sufficient to completely cure the thin film but only reached 76% cure for the thicker film, resulting in a lower Tg. The results show that the required processing conditions using a conventional household microwave to obtain almost complete curing were 1,000 Watts and 10 minutes curing time. In addition, improved curing was achieved in the thicker film because microwave can transmit into polar materials whereas UV cannot penetrate very far into the material. The hot plate curing was observed to produce a higher degree of curing and Tg, however, the uniformity of heating was found to be a major limiting factor of this technique. Slight differences in decomposition profiles of the films cured by different techniques implied slight differences in molecular structures. Compared to UV and hot plate curing, microwave technology was demonstrated as a potential curing technique in the production of PCBs due to its ability to efficiently cure thick films resulting in a strong material with high Tg. To apply the technique to other processes, optimal conditions, i.e. power and time, should be further investigated as well as the prevention of hot spots.

Prediction of Density of Binary Mixtures of Ionic Liquids with Alcohols (Methanol/Ethanol/1-Propanol) using Artificial Neural Network Karen Faith P. Ornedo Ramos; Carla Angela M. Muriel; Adonis P Adornado; Allan N Soriano; Vergel C Bungay
ASEAN Journal of Chemical Engineering Vol 15, No 2 (2015)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Ionic liquids demonstrated successful potential applications in the industry most specifically as the new generation of solvents for catalysis and synthesis in chemical processes, thus knowledge of their physico-chemical properties is of great advantage. The present work presents a mathematical correlation that predicts density of binary mixtures of ionic liquids with various alcohols (ethanol/methanol/1-propanol). The artificial neural network algorithm was used to predict these properties based on the variations in temperature, mole fraction, number of carbon atoms in the cation, number of atoms in the anion, number of hydrogen atoms in the anion and number of carbon atoms in the alcohol. The data used for the calculations were taken from ILThermo Database. Total experimental data points of 1946 for the considered binaries were used to train the algorithm and to test the network obtained. The best neural network architecture determined was found to be 6-6-10-1 with a mean absolute error of 48.74 kg/m3. The resulting correlation satisfactorily represents the considered binary systems and can be used accurately for solvent related calculations requiring properties of these systems.

Mechanical and Thermal Properties of Geopolymers from Mixtures of Coal Ash and Rice Hull Ash using Water Glass Solution as Activator Martin Ernesto L. Kalaw; Alvin B Culaba; Hoc Thang Nguyen; Khoi Nguyen; Hirofumi Hinode; Winarto Kurniawan; Susan M Gallardo; Michael Angelo B. Promentilla
ASEAN Journal of Chemical Engineering Vol 15, No 2 (2015)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Geopolymers, from industrial wastes such as blast furnace slag, red mud, and coal ash, among others, have emerged as technically viable, economically competitive, and environmentally attractive supplements and even alternatives to ordinary Portland cement (OPC). Furthermore, while the most impact shall be achieved with large-scale use in the general building and structural sector, as replacement or supplement to OPC, the properties of these geopolymers may be optimized for special niche applications. One of these applications is for light weight, low thermal conductivity, heat resistant, and moderate strength cement binder for low rise residential buildings. In this study, compressive strength, heat resistance, volumetric weight, mass loss, water absorption and thermal conductivity of geopolymers formed from mixtures of coal bottom ash and rice hull ash (CBA-RHA) and coal fly ash and rice hull ash (CFA-RHA) with sodium silicate solution (modulus 2.5) as activator were evaluated. Using mixture design and the JMP statistical software, the CBA-RHA combination at a mass ratio of 46% CBA, 32% RHA with 22% WGS gave properties at maximum desirability of 17.6 MPa compressive strength, 1640 kg/m3 volumetric weight, 273 kg/m3 water absorption, 28 MPa compressive strength after high temperature exposure (1000oC for 2 hours) with 4.4% mass loss, and 0.578 W/m-K thermal conductivity. On a performance basis, even as the geopolymers are formed as paste, these properties fall within the standards for lightweight OPC based-concrete with strength requirements for residential buildings. The low thermal conductivity and higher strength after high temperature exposure vis-à-vis OPC are additional advantages for consideration.

Preliminary Study: Kinetics of Oil Extraction from Sandalwood by Microwave-assisted Hydrodistillation Heri Septya Kusuma; Mahfud Mahfud
ASEAN Journal of Chemical Engineering Vol 15, No 2 (2015)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Sandalwood and its oil, is one of the oldest known perfume materials and has a long history (more than 4000 years) of use as mentioned in Sanskrit manuscripts. Sandalwood oil plays an important role as an export commodity in many countries and its widely used in the food, perfumery and pharmaceuticals industries. The aim of this study is to know and verify the kinetics and mechanism of microwave-assisted hydrodistillation of sandalwood based on a second-order model. In this study, microwave-assisted hydrodistillation is used to extract essential oils from sandalwood. The extraction was carried out in ten extraction cycles of 15 min to 2.5 hours. The initial extraction rate, the extraction capacity and the second-order extraction rate constant were calculated using the model. Kinetics of oil extraction from sandalwood by microwave-assisted hydrodistillation proved that the extraction process was based on the second-order extraction model as the experimentally done in three different steps. The initial extraction rate, h, was 0.0232 g L-1 min-1, the extraction capacity, CS, was 0.6015 g L-1, the second-order extraction rate constant, k, was 0.0642 L g-1 min-1 and coefficient of determination, R2, was 0.9597.

Page 1 of 1 | Total Record : 6

Filter by Year

2016 2016

Filter By Issues

All Issue Vol 23, No 3 (2023) Vol 23, No 2 (2023) Vol 23, No 1 (2023) Vol 22, No 2 (2022) Vol 22, No 1 (2022) Vol 21, No 2 (2021) Vol 21, No 1 (2021) Vol 20, No 2 (2020) Vol 20, No 1 (2020) Vol 19, No 2 (2019) Vol 19, No 1 (2019) Vol 18, No 2 (2018) Vol 17, No 1 (2017) Vol 18, No 1 (2018) Vol 17, No 2 (2017) Vol 16, No 2 (2016) Vol 16, No 1 (2016) Vol 15, No 2 (2015) Vol 15, No 1 (2015) Vol 14, No 2 (2014) Vol 14, No 1 (2014) Vol 13, No 2 (2013) Vol 13, No 1 (2013) Vol 12, No 2 (2012) Vol 12, No 1 (2012) Vol 11, No 2 (2011) Vol 11, No 1 (2011) Vol 10, No 2 (2010) Vol 10, No 1 (2010) Vol 9, No 2 (2009) Vol 9, No 1 (2009) Vol 8, No 1 & 2 (2008) Vol 2, No 1 (2002) Vol 7, No 1 & 2 (2007) vol. 6 no. 2 (2006) Vol 6, No 1 (2006) Vol 5, No 2 (2005) Vol 5, No 1 (2005) Vol 4, No 2 (2004) Vol 4, No 1 (2004) Vol 3, No 1 (2003) Vol 1, No 1 (2001) More Issue

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

Abstract

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

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