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The Application of Dielectric Barrier Discharge Plasma on Fischer-Tropsch Synthesis: A Review Teuku Mukhriza; Hartati Oktarina
Jurnal Serambi Engineering Vol 6, No 2: April 2021
Publisher : Fakultas Teknik

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32672/jse.v6i2.2890

Fischer-Tropsch (FT) Synthesis has been widely known for centuries as the process of converting syngas to liquid fuels. Several reactors including Slurry bubble column, fluidized-bed, and fixed bed reactors have been used for FTS on an industrial scale. Although science has seen remarkable development in technology for FT synthesis, the industry still faces challenges in optimizations of process parameters and achieved desired selectivity. Extensive research has been continuously conducted to seek the best FT reactor offering heat uniformity and efficient heat transfer across the reactor to increase the catalytic activity and its lifetime. Dielectric Barrier Discharge (DBD) plasma has become one of the options to deal with these issues. This reactor work under low temperature delivers a synergistic effect between plasma and catalyst to break H2 and CO bond. DBD plasma is also suitable for feedstock with high H2/CO molar ratios. It is also found that FT catalyst such as cobalt catalyst used in DBD plasma was well dispersed on the support which in turn favour the selectivity toward liquid hydrocarbon.

A Review on the Impact of Silver Nanoparticles on Soil Microorganisms and Bioremediation as Heavy Metal Removal Technology Hartati Oktarina; Teuku Mukhriza
Jurnal Serambi Engineering Vol 6, No 2: April 2021
Publisher : Fakultas Teknik

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32672/jse.v6i2.2892

The increasing and varied use of silver nanoparticles (AgNPs) as antimicrobial on consumer products increases the risk of the nanomaterial release into the environment and potentially harm beneficial microorganisms in soil. Any change in soil microbial composition will lead to soil quality degradation that eventually reduce crop productivity. The negative effect of AgNPs on soil microorganism has been reported by researchers. There are technologies employed to remove heavy metals from soil such as chemical, physical, and biological technique. However, chemical and physical techniques have some disadvantages e.g high cost and partial removal. Therefore, biological technique including the use of microorganisms (bioremediation) become more favourable. The technique is considered as cost effectiveness and environmentally sustainable method. The present paper summarizes the impact of AgNPs on soil microorganisms and the use of microorganisms (bacteria, fungi, algae, and yeast) to eliminate heavy metals pollution in soil.

Comparative Study between ADMS and CFD in Modeling Dust Dispersion from a Blasting Events in Quarry Wahyu Rinaldi; Teuku Mukhriza
Jurnal Rekayasa Kimia & Lingkungan Vol 8, No 2 (2011): Jurnal Rekayasa Kimia & Lingkungan
Publisher : Chemical Engineering Department, Syiah Kuala University, Banda Aceh, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (501.072 KB)

Two frequently used methods in atmospheric dispersion modeling (ADMS and CFD) were compared in this study to predict pit retention within an open quarry. Conventional Gaussian plume models developed by CERC, ADMS 3 and ADMS 4, were used to predict the pit retention. This study mimicked Fluent CFD modeling of dust dispersion of a blasting event in Old Moor Quarry. A single blast event that liberated a typical 25,000 tons of rock released 1,900 kg of Total Suspended Particle (TSP). The emission source geometry was defined as a three dimensional block volume source of 70 m normal to the face, 80 m in width and 20 m in height. It was also assumed the TSP liberated over one hour had an emission rate of 4.71x10-3 g/m3/s. The four particle sizes were defined as 2.5, 10, 30 and 75 m at mass fractions of 0.05, 0.45, 0.3 and 0.2 respectively and the particles were assumed have uniform limestone density of 2600 kg/m3. The results indicated that ADMS and model based on CFD indicates similar trend, that is, pit retention is proportional to distance from source to pit edge along wind direction and proportional to inverse quarry gradient.Keywords: dust dispersion, blasting, ADMS, CFD, pit retention

Microwave Assisted Co/SiO2 preparation for Fischer-Tropsch synthesis TEUKU MUKHRIZA; KUI ZHANG; ANH N. PHAN
Jurnal Natural Volume 20 Number 2, June 2020
Publisher : Universitas Syiah Kuala

Cobalt catalyst has been widely used for Fischer-Tropsch (FT) Synthesis in Industry. The most common method to prepare cobalt catalyst is impregnations. Metal is deposited on porous support by contacting dry support with solution containing dissolved cobalt precursor. This step will follow by drying, calcination and reduction. The heating step used in this conventional method, however, may lead to the formation of metal silicate which is inactive site for catalysis. In this study, author explore the use of microwave to prepare catalyst compared to conventional drying method. Cobalt catalyst with SiO2 support was prepared and characterized. Particle size, surface area, and cobalt content were investigated. Crystallite size of 3-8 nm was formed which was reported to be the optimum size for cobalt catalyst in FT Synthesis. Scanning Electron Microscope (SEM) and Transmission Electron Microscopy (TEM) image revealed that microwave catalyst showed better uniformity and cobalt dispersion on silica support. Thermo-Gravimetric Analysis (TGA) study also indicated that this catalyst has good stability at Low Temperature Fischer-Tropsch Synthesis. The catalysts were then applied plasma assisted FT process over a range of power plasma (20-60W) to investigate the effect on the conversion and selectivity. The results showed that microwave catalyst exhibit lower CO conversion at 42.06% compared to conventional method at 68.32%. However, microwave catalyst is more favourable for long chain hydrocarbon selectivity.

Differential tolerance of Trichoderma harzianum and Rhizoctonia solani towards silver nanoparticles: potential for agricultural applications? HARTATI OKTARINA; TEUKU MUKHRIZA; LIDIJA ŠILLER; IAN SINGLETON
Jurnal Natural Volume 22 Number 2, June 2022
Publisher : Universitas Syiah Kuala

In the previous study, we examined the effect of silver nanoparticles (AgNPs) on beneficial soil fungus including Trichoderma harzianum (T22), and pathogenic soil-borne fungus, Rhizoctonia solani (AG3-PT). The result exhibited that T. harzianum (T22) is tolerance towards AgNPs. On the other hand, the pathogenic fungi, R.solani (AG3-PT), is more sensitive to AgNPs. T. harzianum is well known as biocontrol agent to suppress R. solani. Therefore, in this study we investigated the combination of T. harzianum (T22) and AgNPs at low concentration to control two strains of R. solani (AG3-PT and AG2-1). The effect of AgNPs at two different levels (20 mg L-1 and 50 mg L-1) was examined over the growth of the two strains of R. solani and T. harzianum (T22) using dual culture technique. The results shows that this combination have a potential to reduce colony growth of R. solani (AG2-1) at higher AgNPs concentration. However, it was not the case for R. solani (AG3-PT). It can be concluded that AgNPs toxicity depend on several factors including species strain and the size of AgNPs particle.

Antioxidant Activity of Aceh Curry Leaves (Murraya Koenigii) Extracted Using Various Solvents Desy Anggriani; Lisa Azila; Cut Meurah Rosnelly; Hisbullah Hisbullah; Syaubari Syaubari; Teuku Mukhriza
Journal of Applied Technology Vol 10, No 1 (2023)
Publisher : Journal of Applied Technology

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (244.098 KB)

Free radicals are molecules that are highly reactive and contain unpaired electrons. These molecules are harmful to healthy cells. Antioxidants have the ability to neutralise free radicals by donating one of their electrons to the molecules that make up free radicals. This prevents free radicals from wreaking havoc on healthy cells. Curry leaf, also known as Murraya Koenigii, is a member of the Rutaceae family and is a spice that is commonly used. By gauging the degree to which various solvents and ratios are able to extract antioxidants from curry leaves, the objective of this study is to find the optimal solvent and combination for doing so. A Soxhlet and a solvent mixture consisting of hexane, chloroform, and ethanol in a ratio of 1:10 were used to extract the anti-oxidant components of curry leaves. With a yield percentage of 30.53 percent, the ethanol solvent proved to be the most efficient of the three in terms of extracting antioxidants from the sample. Not only did extracts of curry leaves obtained from the ethanol solvent have the best yield (when compared to extracts derived from other solvents), but they also have the highest levels of inhibition (54.42%) and antioxidant activity (40.667 ppm) when it comes to catching free radicals.

Antioxidant Activity of Aceh Curry Leaves (Murraya Koenigii) Extracted Using Various Solvents Desy Anggriani; Lisa Azila; Cut Meurah Rosnelly; Hisbullah Hisbullah; Syaubari Syaubari; Teuku Mukhriza
Journal of Applied Technology Vol 10, No 1 (2023)
Publisher : Journal of Applied Technology

Show Abstract | Download Original | Original Source | Check in Google Scholar

Free radicals are molecules that are highly reactive and contain unpaired electrons. These molecules are harmful to healthy cells. Antioxidants have the ability to neutralise free radicals by donating one of their electrons to the molecules that make up free radicals. This prevents free radicals from wreaking havoc on healthy cells. Curry leaf, also known as Murraya Koenigii, is a member of the Rutaceae family and is a spice that is commonly used. By gauging the degree to which various solvents and ratios are able to extract antioxidants from curry leaves, the objective of this study is to find the optimal solvent and combination for doing so. A Soxhlet and a solvent mixture consisting of hexane, chloroform, and ethanol in a ratio of 1:10 were used to extract the anti-oxidant components of curry leaves. With a yield percentage of 30.53 percent, the ethanol solvent proved to be the most efficient of the three in terms of extracting antioxidants from the sample. Not only did extracts of curry leaves obtained from the ethanol solvent have the best yield (when compared to extracts derived from other solvents), but they also have the highest levels of inhibition (54.42%) and antioxidant activity (40.667 ppm) when it comes to catching free radicals.

Microwave Assisted Co/SiO2 preparation for Fischer-Tropsch synthesis TEUKU MUKHRIZA; KUI ZHANG; ANH N. PHAN
Jurnal Natural Volume 20 Number 2, June 2020
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v20i2.16889

Cobalt catalyst has been widely used for Fischer-Tropsch (FT) Synthesis in Industry. The most common method to prepare cobalt catalyst is impregnations. Metal is deposited on porous support by contacting dry support with solution containing dissolved cobalt precursor. This step will follow by drying, calcination and reduction. The heating step used in this conventional method, however, may lead to the formation of metal silicate which is inactive site for catalysis. In this study, author explore the use of microwave to prepare catalyst compared to conventional drying method. Cobalt catalyst with SiO2 support was prepared and characterized. Particle size, surface area, and cobalt content were investigated. Crystallite size of 3-8 nm was formed which was reported to be the optimum size for cobalt catalyst in FT Synthesis. Scanning Electron Microscope (SEM) and Transmission Electron Microscopy (TEM) image revealed that microwave catalyst showed better uniformity and cobalt dispersion on silica support. Thermo-Gravimetric Analysis (TGA) study also indicated that this catalyst has good stability at Low Temperature Fischer-Tropsch Synthesis. The catalysts were then applied plasma assisted FT process over a range of power plasma (20-60W) to investigate the effect on the conversion and selectivity. The results showed that microwave catalyst exhibit lower CO conversion at 42.06% compared to conventional method at 68.32%. However, microwave catalyst is more favourable for long chain hydrocarbon selectivity.

Differential tolerance of Trichoderma harzianum and Rhizoctonia solani towards silver nanoparticles: potential for agricultural applications? HARTATI OKTARINA; TEUKU MUKHRIZA; LIDIJA ŠILLER; IAN SINGLETON
Jurnal Natural Volume 22 Number 2, June 2022
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v22i2.24149

In the previous study, we examined the effect of silver nanoparticles (AgNPs) on beneficial soil fungus including Trichoderma harzianum (T22), and pathogenic soil-borne fungus, Rhizoctonia solani (AG3-PT). The result exhibited that T. harzianum (T22) is tolerance towards AgNPs. On the other hand, the pathogenic fungi, R.solani (AG3-PT), is more sensitive to AgNPs. T. harzianum is well known as biocontrol agent to suppress R. solani. Therefore, in this study we investigated the combination of T. harzianum (T22) and AgNPs at low concentration to control two strains of R. solani (AG3-PT and AG2-1). The effect of AgNPs at two different levels (20 mg L-1 and 50 mg L-1) was examined over the growth of the two strains of R. solani and T. harzianum (T22) using dual culture technique. The results shows that this combination have a potential to reduce colony growth of R. solani (AG2-1) at higher AgNPs concentration. However, it was not the case for R. solani (AG3-PT). It can be concluded that AgNPs toxicity depend on several factors including species strain and the size of AgNPs particle.

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