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All Journal Journal of Engineering and Technological Sciences Chemistry Indonesian Journal of Chemical Research Bulletin of Chemical Reaction Engineering & Catalysis Journal of Engineering and Technological Sciences
Melia Laniwati Gunawan
Chemical Engineering Program, Bandung Institute of Technology, Jalan Ganesha 10 Bandung 40132, Indonesia
Aerospace Engineering Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Electrical & Electronics Engineering Engineering Environmental Science

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 1 
Synthesis and Activity Test of Cu/ZnO/Al2O3 for the Methanol Steam Reforming as a Fuel Cell’s Hydrogen Supplier Makertihartha, IGBN; Subagjo, Subagjo; Gunawan, Melia Laniwati
Journal of Engineering and Technological Sciences Vol 41, No 1 (2009)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (532.438 KB) | DOI: 10.5614/itbj.eng.sci.2009.41.1.3

Abstract

The  synthesis  of  hydrogen  from  hydrocarbons  through  the  steam reforming  of  methanol  on  Cu/ZnO/Al2O3  catalyst  has  been  investigated.  This process is assigned to be one of the promising alternatives for  fuel cell hydrogen process source. Hydrogen synthesis from methanol can be carried out by means of  methanol  steam  reforming  which  is  a  gas  phase  catalytic  reaction  between methanol and water. In this research, the  Cu/ZnO/Al2O3  catalyst  prepared by the dry  impregnation  was  used.  The  specific  surface  area  of  catalyst  was  194.69 m2/gram.The  methanol  steam  reforming  (SRM)  reaction  was  carried  out  by means of the injection of gas mixture containing methanol and water with 1:1.2 mol ratio and 20-90 mL/minute feed  flow rate to a fixed bed reactor loaded by 1 g of catalyst. The reaction temperature was 200-300 °C, and the reactor pressure was 1 atm. Preceding  the reaction, catalyst was reduced in the H2/N2  mixture at 160  °C.  This  study  shows  that  at  300  °C  reaction  temperature,  methanol conversion  reached  100%  at  28  mL/minute  gas  flow  rate.  This  conversion decreased  significantly  with  the  increase  of  gas  flow  rate.  Meanwhile,  the catalyst prepared for SRM  was stable in 36 hours of operation at 260  °C. The catalyst exhibited a good stability although the reaction condition was shifted to a higher gas flow rate.
Synthesis of NaY Zeolite Using Mixed Calcined Kaolins Subagjo, Subagjo; Rahayu, Endang Sri; Samadhi, Tjokorde Walmiki; Gunawan, Melia Laniwati
Journal of Engineering and Technological Sciences Vol 47, No 6 (2015)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (257.138 KB) | DOI: 10.5614/j.eng.technol.sci.2015.47.6.4

Abstract

Kaolin is one of several types of clay minerals. The most common crystalline phase constituting kaolin minerals is kaolinite, with the chemical composition Al2Si2O5(OH)4. Kaolin is mostly used for manufacturing traditional ceramics and also to synthesize zeolites or molecular sieves. The Si-O and Al-O structures in kaolin are inactive and inert, so activation by calcination is required. This work studies the conversion of kaolin originating from Bangka island in Indonesia into calcined kaolin phase as precursor in NaY zeolite synthesis. In the calcination process, the kaolinite undergoes phase transformations from metakaolin to mullite. The Bangka kaolin is 74.3% crystalline, predominantly composed of kaolinite, and 25.7% amorphous, with an SiO2/Al2O3 mass ratio of 1.64. Thermal characterization using simultaneous DSC/TGA identified an endothermic peak at 527°C and an exothermic peak at 1013°C. Thus, three calcination temperatures (700, 1013, and 1050 °C) were selected to produce calcined kaolins with different phase distributions. The best product, with 87.8% NaY zeolite in the 54.7% crystalline product and an SiO2/Al2O3 molar ratio of 5.35, was obtained through hydrothermal synthesis using mixed calcined kaolins with a composition of K700C : K1013C : K1050C = 10 : 85 : 5 in %-mass, with seed addition, at a temperature of 93 °Cand a reaction time of 15 hours.
Kinetika Reaksi Hidrogenasi Ester Lemak Menjadi Alkohol Lemak Dengan Katalis Tembaga- Mangan Gunawan, Melia Laniwati; Makertihartha, IGBN; Subagjo, Subagjo
Indonesian Journal of Chemical Research Vol 8 No 1 (2020): Edisi Bulan Mei (Edition for May)
Publisher : Jurusan Kimia, Fakultas Sains dan Teknologi, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598/ijcr.2020.8-mel

Abstract

Fatty alcohol (FAOH) can be produced by hydrogenating of fatty acid methyl ester (FAME) using the copper-based catalyst. Copper-Chrom (Cu-Cr) is the best catalyst for high-pressure reaction condition, which is copper (Cu) as the main active component and chrom (Cr) as a promoter. Since Cr is feared to be toxic, one of the best replacement candidates is manganese (Mn). The research aims is to find the kinetic equation of hydrogenation FAME to FAOH using a Cu-Mn commercial catalyst. FAME with methyl laurate and methyl myristate as the main compounds is used as feedstock. The main products are lauryl alcohol and myristyl alcohol. The reaction was carried out in an isothermal continuous fixed bed reactor under conditions of temperature 220 – 240 oC, pressure 50 bar, and liquid hourly space velocity (LHSV) 5-12.5 hr-1. The kinetic equation is determined using the power law model. The FAME hydrogenation on copper - manganese catalyst is the half order reaction. The activation energy value is 86.32 kJ/mol and the Arrhenius constant value is 5.87x106 M0.5/s.
Investigation on the Hydrothermal Condition in Synthesis of Active Matrix from Metakaolin: Physicochemical Properties and Intrinsic Cracking Activities Hudaya, Farhansyah Yusuf Putra; Anggaswara, Rezky Oktaviandy; Gunawan, Melia Laniwati; Kadja, Grandprix Thomryes Marth; Makertihartha, I. G. B. N.
Bulletin of Chemical Reaction Engineering & Catalysis 2024: BCREC Volume 19 Issue 3 Year 2024 (October 2024)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20181

Abstract

The current trends in research and development of FCC catalyst is focused on the formulation of active matrices that serve as pre-crackers, with the objective of reducing the diffusional resistance of the longer chain hydrocarbon molecule in the feed. In this study, an aluminosilicate active matrix was synthesised from metakaolin using hydrothermal method. The experimental variables that were varied were hydrothermal temperature, in the range of 80 to 110 °C, and hydrothermal time, in the range of 12 to 72 hours, to investigate the best conditions for synthesising the active matrix. Subsequently, the active matrix was subjected to a series of analyses, including X-ray fluorescence, X-ray diffraction, N2 physisorption, NH3-temperature programmed desorption, Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetry, with the objective of determining its composition, crystal characteristics, surface characteristics, acidity, functional groups, material structure, and thermal characteristics. Additionally, the active matrix was tested for its intrinsic cracking activity using the micro activity test (MAT). The results indicate that the best temperature for hydrothermal synthesis of the active matrix is 80 °C. The active matrix synthesised with a heating time of 24 hours demonstrated the highest light cycle oil yield, reaching 38.9 wt%. Meanwhile, the active matrix synthesised at 48 hours exhibited the most favourable characteristics, with a specific surface area of 144.23 m2/g and a pore volume of 0.9933 cm3/g, as well as the highest cracking conversion of 70.0 wt%. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Investigation of the Effect of Silica and Phosphorus Content on the Performance of Active Matrix as Component of Cracking Catalyst Gunawan, Melia Laniwati; Rasrendra, Carolus Borromeus; Widikrama, Candra Lutfi; Kurniawan, Rizky Gilang; Nisa, Lita Marina; Hudaya, Farhansyah Yusuf Putra; Makertihartha, I G. B. N.; Subagjo, Subagjo
Journal of Engineering and Technological Sciences Vol. 56 No. 2 (2024)
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2024.56.2.3

Abstract

Fluid catalytic cracking (FCC) is a technique that converts heavy-fraction feed into fuel. The FCC catalyst components consist of a composite material made of zeolite, filler, binder, and an active matrix. The active matrix is used as a pre-cracker for the heavy-fraction feed. This study examined the impact of the Si/Al ratio and the addition of phosphorus on the physical properties and activity of the active matrix. The synthesis technique refers to US patent 6723297 B2. The utilized variants consisted of SiO2 ranging from 50 to 80 weight percent and a phosphorous addition ranging from 1 to 2 weight percent. The physical characteristics of the active matrix were assessed using nitrogen physisorption and NH3-Temperature programmed adsorption/desorption techniques. A chemical activity test was conducted using the micro activity test (MAT) method, with vacuum gas oil (VGO) as the feedstock. This test was done in accordance with the ASTM D 5154 – 03 standard. The results indicated that the silica composition in the active matrix is directly related to the average pore diameter but inversely related to the specific surface area. Additionally, the inclusion of phosphorus had a similar impact. The silica-alumina-phosphorous variant containing 75%-wt of SiO2 exhibited the most superior active matrix activity, achieving the maximum acquisition of light cycle oil (LCO) at 33%-wt.
Co-Authors Anggaswara, Rezky Oktaviandy Endang Sri Rahayu Hudaya, Farhansyah Yusuf Putra IGBN Makertihartha IGBN Makertihartha Kadja, Grandprix Thomryes Marth Kurniawan, Rizky Gilang Makertihartha, I G. B. N. Makertihartha, I. G. B. N. Nisa, Lita Marina Rasrendra, Carolus Borromeus Subagjo Subagjo Subagjo Subagjo Tjokorde Walmiki Samadhi Widikrama, Candra Lutfi