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Research paper thumbnail of Comparison of Natural Fiber Types as Reinforcement Material on Composite Mechanical Properties via Carbon Nanotubes Addition

IOP Conference Series: Materials Science and Engineering, 2021

Composites with natural fiber reinforcement have been widely used in various field. Natural fiber... more Composites with natural fiber reinforcement have been widely used in various field. Natural fibers have the advantages of easy recycling, environmentally-friendly characters, renewable, non-toxic, inexpensive, high toughness, good insulation against heat and noise, and good thermal properties. The aim of this paper is compare natural fibers used as reinforcing material on composite with an epoxy matrix and the addition of carbon nanotubes (CNT). The natural fibers used are oil palm empty fruit bunches (OPEFB), bagasse, and hemp fiber. Alkalization treatment with NaOH was carried out on natural fibers to remove impurities on the fiber surface and activate hydroxyl groups. CNTs need to be functionalized to achieve the desired compatibility. Functionalization is carried out by the mild acid oxidation method using nitric acid and hydrogen peroxide. Silane coupling agent treatment is carried out on natural fibers and CNTs to improve compatibility with the matrix. The result of the bendin...

Research paper thumbnail of Synthesis and characterization of hydrogel from cellulose derivatives of water hyacinth (Eichhornia crassipes) through chemical cross-linking method by using citric acid

journal of engineering science and technology, 2015

Hydrogels are defined as a three-dimensional polymer structures that can be formed from natural o... more Hydrogels are defined as a three-dimensional polymer structures that can be formed from natural or synthetic polymers and are able to retain large amounts of water. Hydrogels can be made in two ways, i.e. physical cross-linking and chemical cross-linking. The stable structure and effective swelling of the hydrogel can be obtained through the chemical cross-linking process. In this study, hydrogel was made by natural polymer that is non-toxic. Hydrogels were synthesized by using cellulose or its derivatives (Carboxymethyl Cellulose (CMC)) through chemical crosslinking process with citric acid as crosslinking agent. Cellulose is derived from water hyacinth plant, as one of the potent ial sources of cellulosic fibres in producing of CMC. Various conditions of preparation, such as citric acid concentration and variations in the value of the degree of substitution of NaCMC, were observed through the hydrogel characterization results. Variations of variables in this research consist of th...

Research paper thumbnail of Techno-economic analysis of pilot scale carbon nanotube production from LPG with Fe-Co-Mo/MgO catalyst in Indonesia

Research paper thumbnail of Modelling and Simulation of Packed Bed Catalytic Converter for Oxidation of Soot in Diesel Powered Vehicles Flue Gas

Modelling and Simulation of Packed Bed Catalytic Converter for Oxidation of Soot in Diesel Powere... more Modelling and Simulation of Packed Bed Catalytic Converter for Oxidation of Soot in Diesel Powered Vehicles Flue Gas. Diesel vehicle is used in Indonesia in very big number. This vehicle exhausts pollutants especially diesel soot that can be reduces by using a catalytic converter to convert the soot to CO2. To obtain the optimal dimension of catalytic converter it is needed a model that can represent the profile of soot weight, temperature and pressure along the catalytic converter. In this study, a model is developed for packed bed catalytic converter in an adiabatic condition based on a kinetic study that has been reported previously. Calculation of developed equations in this model uses Polymath 5.X solver with Range Kutta Method. The simulation result shows that temperature profile along catalytic converter increases with the decrease of soot weight, while pressure profile decreases. The increase of soot weight in entering gas increases the needed converter length. On the other ...

Research paper thumbnail of Copyright @ 2011 By Journal of Sustainable Energy and Environment 7 The Effect of Reaction Time on the Quality of Hydrogen and Carbon Nanotubes Produced Through Catalytic Decomposition of Methane

Abstract: Carbon nanotubes (CNTs) are tubular carbon molecules with superior mechanical, chemical... more Abstract: Carbon nanotubes (CNTs) are tubular carbon molecules with superior mechanical, chemical, optical, and electrical properties. These unique properties make CNTs potentially valuable as hydrogen storage, superconductors, drug delivery and other end-use applications. Catalytic decomposition of methane is a promising method for producing hydrogen and CNTs simultaneously for several reasons: economic, high yield of products, and ease of control. Unfortunately, the presence of a metal catalyst in the CNTs product after reaction causes a negative impact on the quality of CNTs including reducing the electrical resistivity, density, tensile strength and structural properties of the nano tubes which can lead to the reduction of CNTs performance in many applications. Process optimization is needed to produce hydrogen and CNTs with the best quality by varying the reaction time to observe the influence of reaction time on the quality of the CNTs produced through the catalytic decomposit...

Research paper thumbnail of The Effect of Pyrolysis Temperature and Time of Polypropylene on Quality of Carbon Nanotube with Flame Synthesis Method

E3S Web of Conferences

Variations of the pyrolysis temperature and time are carried out to obtain the correlation betwee... more Variations of the pyrolysis temperature and time are carried out to obtain the correlation between those variables and the number of pyrolysis gases, as well as the yield and quality of produced CNT. PP is pyrolyzed at a temperature range of 525-600°C to produce pyrolizate gases. The flame synthesis method is used to convert PP plastic waste into CNT alongside with the use of wired mesh stainless steel type SS 316 as the substrate. The substrate is pre-treated by oxidative heat treatment at 800°C for 10 minutes before the synthesis to breach the outer chromium layer and make grains on the catalytic surface to enable CNT to grow. Pyrolizate gases are mixed with oxygen flowed from a venturi, so combustion reaction occurs. The combustion gas is flowed to the synthesis reactor to produce CNT at 800°C. Characterization of produced CNT is carried out using XRD, GC-FID, and TEM. The highest yield is obtained at the pyrolysis temperature of 525°C for 45 minutes. While the optimal quality ba...

Research paper thumbnail of Mathematical Model Controlled Potassium Chloride Release Systems from Chitosan Microspheres

International Journal of Technology, 2015

Research paper thumbnail of The Effect of Iron-Carbon Ratio and on Carbon Nanotube Synthesis using Camphor and Ferrocene as Carbon Sources in the Gauze Reactor

South African Journal of Chemical Engineering

Research paper thumbnail of Kinetic Model for Triglyceride Hydrolysis Using Lipase: Review

Seri Teknologi (Technology Series …, 2010

Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials... more Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials in food and cosmetic industries such as diacylglycerol, monoacylglycerol, glycerol and fatty acid. In order to design a reactor for utilizing this reaction on industrial scale, constructing a kinetic model is important. Since the substrates are oil and water, the hydrolysis takes place at oil-water interface. Furthermore, the triglyceride has three ester bonds, so that the hydrolysis stepwise proceeds. Thus, the reaction mechanism is very complicated. The difference between the interfacial and bulk concentrations of the enzyme, substrates and products, and the interfacial enzymatic reaction mechanism should be considered in the model.

Research paper thumbnail of Color removal of Polyethylene Terephthalate waste as a raw material for carbon nanotube synthesis

INTERNATIONAL CONFERENCE ON TRENDS IN MATERIAL SCIENCE AND INVENTIVE MATERIALS: ICTMIM 2020

Research paper thumbnail of The effect of optimization HCl addition to dispersibility in carbon nanotubes functionalization as drug delivery

INTERNATIONAL CONFERENCE ON TRENDS IN MATERIAL SCIENCE AND INVENTIVE MATERIALS: ICTMIM 2020

Research paper thumbnail of Utilization of camphor as an alternative carbon source for the synthesis of carbon nanotubes using floating catalyst

Journal of Physics: Conference Series

Research paper thumbnail of Carbon nanotubes shynthesis in fluidized bed reactor equipped with a cyclone

IOP Conference Series: Materials Science and Engineering

Research paper thumbnail of The effect of hydrochloric acid addition to increase carbon nanotubes dispersibility as drug delivery system by covalent functionalization

IOP Conference Series: Materials Science and Engineering

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licenc... more Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Research paper thumbnail of Identification of Carbon loss in the production of pilot-scale Carbon nanotube using gauze reactor

IOP Conference Series: Materials Science and Engineering

Carbon loss more than 65% was the major obstacles in the Carbon Nanotube (CNT) production using g... more Carbon loss more than 65% was the major obstacles in the Carbon Nanotube (CNT) production using gauze pilot scale reactor. The results showed that the initial carbon loss calculation is 27.64%. The calculation of carbon loss, then, takes place with various corrections parameters of: product flow rate error measurement, feed flow rate changes, gas product composition by Gas Chromatography Flame Ionization Detector (GC FID), and the carbon particulate by glass fiber filters. Error of product flow rate due to the measurement with bubble soap gives calculation error of carbon loss for about ± 4.14%. Changes in the feed flow rate due to CNT growth in the reactor reduce carbon loss by 4.97%. The detection of secondary hydrocarbon with GC FID during CNT production process reduces carbon loss by 5.14%. Particulates carried by product stream are very few and merely correct the carbon loss about 0.05%. Taking all the factors into account, the amount of carbon loss within this study is (17.21 ± 4.14)%. Assuming that 4.14% of carbon loss is due to the error measurement of product flow rate, the amount of carbon loss is 13.07%. It means that more than 57% of carbon loss within this study is identified.

Research paper thumbnail of Synthesis of ACNT on quartz substrate with catalytic decomposition reaction from Cinnamomum camphora by using FC-CVD method

Research paper thumbnail of The development of Ti6Al4V based anti bacterial dental implant modified with TiO2 nanotube arrays doped silver metal (Ag)

Research paper thumbnail of Photocatalytic activity of titania nanotube (tint)-carbon nanotube (CNT) composite for degradation of phenol

Research paper thumbnail of Side Effects of Nitrification Inhibitors on Non Target Microbial Processes in Soils

Jurnal TANAH TROPIKA (Journal of Tropical Soils), 2011

Research paper thumbnail of Kinetic Model for Triglyceride Hydrolysis Using Lipase: Review

MAKARA of Technology Series, 2010

Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials... more Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials in food and cosmetic industries such as diacylglycerol, monoacylglycerol, glycerol and fatty acid. In order to design a reactor for utilizing this reaction on industrial scale, constructing a kinetic model is important. Since the substrates are oil and water, the hydrolysis takes place at oil-water interface. Furthermore, the triglyceride has three ester bonds, so that the hydrolysis stepwise proceeds. Thus, the reaction mechanism is very complicated. The difference between the interfacial and bulk concentrations of the enzyme, substrates and products, and the interfacial enzymatic reaction mechanism should be considered in the model.

Research paper thumbnail of Comparison of Natural Fiber Types as Reinforcement Material on Composite Mechanical Properties via Carbon Nanotubes Addition

IOP Conference Series: Materials Science and Engineering, 2021

Composites with natural fiber reinforcement have been widely used in various field. Natural fiber... more Composites with natural fiber reinforcement have been widely used in various field. Natural fibers have the advantages of easy recycling, environmentally-friendly characters, renewable, non-toxic, inexpensive, high toughness, good insulation against heat and noise, and good thermal properties. The aim of this paper is compare natural fibers used as reinforcing material on composite with an epoxy matrix and the addition of carbon nanotubes (CNT). The natural fibers used are oil palm empty fruit bunches (OPEFB), bagasse, and hemp fiber. Alkalization treatment with NaOH was carried out on natural fibers to remove impurities on the fiber surface and activate hydroxyl groups. CNTs need to be functionalized to achieve the desired compatibility. Functionalization is carried out by the mild acid oxidation method using nitric acid and hydrogen peroxide. Silane coupling agent treatment is carried out on natural fibers and CNTs to improve compatibility with the matrix. The result of the bendin...

Research paper thumbnail of Synthesis and characterization of hydrogel from cellulose derivatives of water hyacinth (Eichhornia crassipes) through chemical cross-linking method by using citric acid

journal of engineering science and technology, 2015

Hydrogels are defined as a three-dimensional polymer structures that can be formed from natural o... more Hydrogels are defined as a three-dimensional polymer structures that can be formed from natural or synthetic polymers and are able to retain large amounts of water. Hydrogels can be made in two ways, i.e. physical cross-linking and chemical cross-linking. The stable structure and effective swelling of the hydrogel can be obtained through the chemical cross-linking process. In this study, hydrogel was made by natural polymer that is non-toxic. Hydrogels were synthesized by using cellulose or its derivatives (Carboxymethyl Cellulose (CMC)) through chemical crosslinking process with citric acid as crosslinking agent. Cellulose is derived from water hyacinth plant, as one of the potent ial sources of cellulosic fibres in producing of CMC. Various conditions of preparation, such as citric acid concentration and variations in the value of the degree of substitution of NaCMC, were observed through the hydrogel characterization results. Variations of variables in this research consist of th...

Research paper thumbnail of Techno-economic analysis of pilot scale carbon nanotube production from LPG with Fe-Co-Mo/MgO catalyst in Indonesia

Research paper thumbnail of Modelling and Simulation of Packed Bed Catalytic Converter for Oxidation of Soot in Diesel Powered Vehicles Flue Gas

Modelling and Simulation of Packed Bed Catalytic Converter for Oxidation of Soot in Diesel Powere... more Modelling and Simulation of Packed Bed Catalytic Converter for Oxidation of Soot in Diesel Powered Vehicles Flue Gas. Diesel vehicle is used in Indonesia in very big number. This vehicle exhausts pollutants especially diesel soot that can be reduces by using a catalytic converter to convert the soot to CO2. To obtain the optimal dimension of catalytic converter it is needed a model that can represent the profile of soot weight, temperature and pressure along the catalytic converter. In this study, a model is developed for packed bed catalytic converter in an adiabatic condition based on a kinetic study that has been reported previously. Calculation of developed equations in this model uses Polymath 5.X solver with Range Kutta Method. The simulation result shows that temperature profile along catalytic converter increases with the decrease of soot weight, while pressure profile decreases. The increase of soot weight in entering gas increases the needed converter length. On the other ...

Research paper thumbnail of Copyright @ 2011 By Journal of Sustainable Energy and Environment 7 The Effect of Reaction Time on the Quality of Hydrogen and Carbon Nanotubes Produced Through Catalytic Decomposition of Methane

Abstract: Carbon nanotubes (CNTs) are tubular carbon molecules with superior mechanical, chemical... more Abstract: Carbon nanotubes (CNTs) are tubular carbon molecules with superior mechanical, chemical, optical, and electrical properties. These unique properties make CNTs potentially valuable as hydrogen storage, superconductors, drug delivery and other end-use applications. Catalytic decomposition of methane is a promising method for producing hydrogen and CNTs simultaneously for several reasons: economic, high yield of products, and ease of control. Unfortunately, the presence of a metal catalyst in the CNTs product after reaction causes a negative impact on the quality of CNTs including reducing the electrical resistivity, density, tensile strength and structural properties of the nano tubes which can lead to the reduction of CNTs performance in many applications. Process optimization is needed to produce hydrogen and CNTs with the best quality by varying the reaction time to observe the influence of reaction time on the quality of the CNTs produced through the catalytic decomposit...

Research paper thumbnail of The Effect of Pyrolysis Temperature and Time of Polypropylene on Quality of Carbon Nanotube with Flame Synthesis Method

E3S Web of Conferences

Variations of the pyrolysis temperature and time are carried out to obtain the correlation betwee... more Variations of the pyrolysis temperature and time are carried out to obtain the correlation between those variables and the number of pyrolysis gases, as well as the yield and quality of produced CNT. PP is pyrolyzed at a temperature range of 525-600°C to produce pyrolizate gases. The flame synthesis method is used to convert PP plastic waste into CNT alongside with the use of wired mesh stainless steel type SS 316 as the substrate. The substrate is pre-treated by oxidative heat treatment at 800°C for 10 minutes before the synthesis to breach the outer chromium layer and make grains on the catalytic surface to enable CNT to grow. Pyrolizate gases are mixed with oxygen flowed from a venturi, so combustion reaction occurs. The combustion gas is flowed to the synthesis reactor to produce CNT at 800°C. Characterization of produced CNT is carried out using XRD, GC-FID, and TEM. The highest yield is obtained at the pyrolysis temperature of 525°C for 45 minutes. While the optimal quality ba...

Research paper thumbnail of Mathematical Model Controlled Potassium Chloride Release Systems from Chitosan Microspheres

International Journal of Technology, 2015

Research paper thumbnail of The Effect of Iron-Carbon Ratio and on Carbon Nanotube Synthesis using Camphor and Ferrocene as Carbon Sources in the Gauze Reactor

South African Journal of Chemical Engineering

Research paper thumbnail of Kinetic Model for Triglyceride Hydrolysis Using Lipase: Review

Seri Teknologi (Technology Series …, 2010

Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials... more Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials in food and cosmetic industries such as diacylglycerol, monoacylglycerol, glycerol and fatty acid. In order to design a reactor for utilizing this reaction on industrial scale, constructing a kinetic model is important. Since the substrates are oil and water, the hydrolysis takes place at oil-water interface. Furthermore, the triglyceride has three ester bonds, so that the hydrolysis stepwise proceeds. Thus, the reaction mechanism is very complicated. The difference between the interfacial and bulk concentrations of the enzyme, substrates and products, and the interfacial enzymatic reaction mechanism should be considered in the model.

Research paper thumbnail of Color removal of Polyethylene Terephthalate waste as a raw material for carbon nanotube synthesis

INTERNATIONAL CONFERENCE ON TRENDS IN MATERIAL SCIENCE AND INVENTIVE MATERIALS: ICTMIM 2020

Research paper thumbnail of The effect of optimization HCl addition to dispersibility in carbon nanotubes functionalization as drug delivery

INTERNATIONAL CONFERENCE ON TRENDS IN MATERIAL SCIENCE AND INVENTIVE MATERIALS: ICTMIM 2020

Research paper thumbnail of Utilization of camphor as an alternative carbon source for the synthesis of carbon nanotubes using floating catalyst

Journal of Physics: Conference Series

Research paper thumbnail of Carbon nanotubes shynthesis in fluidized bed reactor equipped with a cyclone

IOP Conference Series: Materials Science and Engineering

Research paper thumbnail of The effect of hydrochloric acid addition to increase carbon nanotubes dispersibility as drug delivery system by covalent functionalization

IOP Conference Series: Materials Science and Engineering

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licenc... more Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Research paper thumbnail of Identification of Carbon loss in the production of pilot-scale Carbon nanotube using gauze reactor

IOP Conference Series: Materials Science and Engineering

Carbon loss more than 65% was the major obstacles in the Carbon Nanotube (CNT) production using g... more Carbon loss more than 65% was the major obstacles in the Carbon Nanotube (CNT) production using gauze pilot scale reactor. The results showed that the initial carbon loss calculation is 27.64%. The calculation of carbon loss, then, takes place with various corrections parameters of: product flow rate error measurement, feed flow rate changes, gas product composition by Gas Chromatography Flame Ionization Detector (GC FID), and the carbon particulate by glass fiber filters. Error of product flow rate due to the measurement with bubble soap gives calculation error of carbon loss for about ± 4.14%. Changes in the feed flow rate due to CNT growth in the reactor reduce carbon loss by 4.97%. The detection of secondary hydrocarbon with GC FID during CNT production process reduces carbon loss by 5.14%. Particulates carried by product stream are very few and merely correct the carbon loss about 0.05%. Taking all the factors into account, the amount of carbon loss within this study is (17.21 ± 4.14)%. Assuming that 4.14% of carbon loss is due to the error measurement of product flow rate, the amount of carbon loss is 13.07%. It means that more than 57% of carbon loss within this study is identified.

Research paper thumbnail of Synthesis of ACNT on quartz substrate with catalytic decomposition reaction from Cinnamomum camphora by using FC-CVD method

Research paper thumbnail of The development of Ti6Al4V based anti bacterial dental implant modified with TiO2 nanotube arrays doped silver metal (Ag)

Research paper thumbnail of Photocatalytic activity of titania nanotube (tint)-carbon nanotube (CNT) composite for degradation of phenol

Research paper thumbnail of Side Effects of Nitrification Inhibitors on Non Target Microbial Processes in Soils

Jurnal TANAH TROPIKA (Journal of Tropical Soils), 2011

Research paper thumbnail of Kinetic Model for Triglyceride Hydrolysis Using Lipase: Review

MAKARA of Technology Series, 2010

Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials... more Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials in food and cosmetic industries such as diacylglycerol, monoacylglycerol, glycerol and fatty acid. In order to design a reactor for utilizing this reaction on industrial scale, constructing a kinetic model is important. Since the substrates are oil and water, the hydrolysis takes place at oil-water interface. Furthermore, the triglyceride has three ester bonds, so that the hydrolysis stepwise proceeds. Thus, the reaction mechanism is very complicated. The difference between the interfacial and bulk concentrations of the enzyme, substrates and products, and the interfacial enzymatic reaction mechanism should be considered in the model.