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Konversi
Published by Universitas Lambung Mangkurat
ISSN : 23023686     EISSN : 25413481     DOI : -
Core Subject : Education,
Education
Arjuna Subject : -
Articles 263 Documents
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Biosynthesis of silver nanoparticles (AgNP) using leaves extract of Jatropha Curcas L. Nury, Dennis Farina; Febriyanto, Pramahadi; Arum, Amalia Sekar; Mayastuti, Sherina; Luthfi, Muhammad Zulfikar
Konversi Vol 12, No 2 (2023): OKTOBER 2023
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v12i2.16610

Abstract

Due to the increased demand for ecologically friendly material synthesis techniques, biosynthesis of nanoparticles has drawn a lot of attention. It has been claimed that an environmentally benign method for producing silver nanoparticles (AgNPs) efficiently can be achieved utilizing leaves extract of the multifunctional plant Jatropha curcas. Maximum absorption were obtained from different types of solvents, in distilled water resulted at wavelength 428-434, meanwhile in ethanol 96% solvent, maximum absorption was obtained at wavelength 338-340 nm by using UV-Vis spectrophotometer, respectively. The results of FTIR formed on silver nanoparticles are O-H functional groups with distilled water and O-H functional groups, and C-O with 96% ethanol solvent. The particle sizes formed in distilled water and 96% ethanol solvents were 104.6 nm and 110.7 nm respectively with PI values of 0.341 and 0.644. Based on the results, (AgNPs) passes the nanoparticle range caused by agglomeration. It can be interpreted that the results of this synthesis are fine particles.
Catalytic co-pyrolysis of coal and polypropylene plastic into liquid fuel Sunarno, Sunarno; Reni Yenti, Silvia; Mutamima, Anisa; Huwaidah Husna, Fathiyah; Rahmat Wicakso, Doni; Isnaini, Muhammad Dody
Konversi Vol 13, No 1 (2024): April 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i1.16043

Abstract

The decline in fossil fuel sources has stimulated research in the field of renewable fuels. Efforts are currently being made to find alternative energy sources that have high efficiency and are environmentally friendly. By looking at the existing problems, research on the co-pyrolysis of coal and polypropylene (PP) plastic into liquid fuel is interesting to do. The co-pyrolysis process was carried out at 400oC and nitrogen gas was flowed with a flow rate of 100 mL/min for 60 minutes with various ratio of raw material coal/PP plastic (100/0, 75/25, 50/50, 25/75), and ratio of CaO catalyst/raw material (0%, 10%, 15%, 20% w/w). The results showed that with the reduction in the ratio of coal/plastic, the yield of liquid fuel increased. Co-pyrolysis of coal: PP plastic with a ratio of 25:75 with the addition of 20% CaO catalyst obtained 37.56% liquid fuel yield with the characteristics of density of 0.839 g/mL, viscosity of 2.51 cSt, calorific value of 46.813 MJ/kg and pH of 2.9.
Effect of long chain fatty acids on biogas production and biochemical kinetics in anaerobic bioreactors: a review Kahar, Abdul; Khoiroh, Ianatul
Konversi Vol 13, No 1 (2024): April 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i1.19035

Abstract

Long Chain Fatty Acids (LCFAs) are the primary intermediate byproduct of the lipid (fats, oils, and greases) degradation process, and if they accumulate in high concentrations, they can cause failure or reduce the performance of anaerobic bioreactors due to sludge flotation issues, biochemical kinetics problems for soluble substrates, inhibition of microbial activity, and inefficient biogas recovery. Understanding the biochemical kinetics of anaerobic bioreactors requires taking into account the entire process, including microbe growth, substrate degradation, and product synthesis. Biochemical kinetics of anaerobic treatment is the study of polymer biodegradation rates of insoluble organic matter in wastewater, which is the mechanism of bond breaking and bond formation in biochemical reactions. As a result, biochemical kinetics allow for the design of both desired and undesirable reaction phases. The kinetic parameters acquired are utilized to design, operate, and optimize anaerobic bioreactors for wastewater treatment on a technical scale.
Chemical and physical activation of natural pyrite as potential inorganic pigment material Iqbal, Rendy Muhamad; Simarmata, Sari Namarito; Sinaga, Tiara Cristy; Simanjutak, Elfrida Roulina; Putra, Riandy; Khaerudini, Deni Shidqi
Konversi Vol 13, No 1 (2024): April 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i1.16947

Abstract

Pyrite is one of the minerals in Borneo Island. It has a disadvantage for soil quality due to its acidity properties. One of the main components of pyrite is iron, which promises to be utilized as an inorganic pigment. This research aims to transform pyrite into red-brown pigment material-based iron oxide. Pyrite mineral transformation through chemical and physical activation, followed by pigment characterization using XRF, XRD, FTIR, and FE-SEM. Based on the XRF result, the highest component is Fe, with a percentage up to 42%. This data is also suitable with an iron oxide phase from the diffractogram of pigment, followed by silica and alumina structure. The heating process successfully changed the color materials from gold to red-brown. Then, the molecular vibration of Fe–O also appears on FTIR spectra at a wavenumber of 483 cm-1 and T–O–T bending at 994 cm-1. Moreover, morphological observation exhibits the aggregation of particles and distribution of iron element spread on the overall area pigment. The color transformation into red-brown pigment can be obtained by pyrite processing into potential inorganic pigment material.
Manufacturing the activated carbon catalyst of impregnated palm core shells for biodiesel production Rifki, Ahmad; Zamhari, Mustain; Purnamasari, Indah
Konversi Vol 13, No 1 (2024): April 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i1.17470

Abstract

This research aims to produce activated carbon-based heterogeneous catalyst derived from palm kernel shells impregnated with a KOH solution and to determine the effects of the concentration of the KOH solution and the time period during impregnation. The variables observed included KOH concentration and impregnation time. The impregnation process used KOH solution with the solution concentrations of 1N, 2N, 3N, 4N and 5N with impregnation process within 18 hours, 21 hours and 24 hours. AAS, FTIR and SEM were analyzed after impregnation with different concentrations and times. The results of the analysis of potassium metal showed the highest absorption occurred at a concentration of 5N within 21 hours at 25.4570%. The application of the activated carbon catalyst from palm kernel shells was conducted in making biodiesel. The process of making biodiesel was carried out with a reaction time of 120 minutes at a temperature of 60℃ with a molar ratio of 1: 12 using a catalyst of 2% (% w/w). Biodiesel yield testing referred to SNI 04-7182-2015. The analysis results obtained showed 879 kg/m3 density, 6.1 cst viscosity, 0.5 acid number, and 174℃ flash point.
Effect of variation concentrations of cajuput oil and magnets on engine performance and flue gas emissions Perdana, Dony; Said, Nur; Mamat, Rizalman
Konversi Vol 13, No 1 (2024): April 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i1.17553

Abstract

This studies proposes the effect of variations concentration of cajupuut oil and magnetic field of attraction on internal combustion engine performance and flue gas emissions. The increasing demand for petroleum energy is increasing, in line with the rising levels of flue gas emissions produced using transportation and the industrial world. Therefore, environmentally friendly alternative fuels are needed. Because the availability of fossil fuels cannot be renewed and their existence is increasingly depleting. This problems can overcome by saving fuels consumption. One way to save fuels are by adding bio-additives from cajupuut oil and a magnetic field to the fuel line. This research uses a direct test method using tools like a chassis dynamometer and gas analyzer. Pertalite fuel is mixed with various concentrations of cajupuut oil, six cc, eight cc, and ten cc and with addition of a magnetic fields strength of 10,000 Gauss of the genio motorcycle fuel line. This research has found that influence of variation of concentration in cajupuut oil and the magnetic field of attraction significantly impact engine performance and flue gas emissions. A mixture of eucalyptus ten ml with a magnetic field of attraction produces the highest maximum power and torque of 8.35 Hp and 11.77 Nm, respectively. Meanwhile, CO emissions have a level of 0.1%, but the highest CO2 level is 9.6% compared to other concentrations.
Simulation of dimethyl ether production as LPG substitute using LNG from Arun terminal with tri-reforming and direct synthesis method Rahmatullah, Faiprianda Assyari; Pamungkas, Tegar; Mutia, Sarah; Zulfansyah, Zulfansyah; Rionaldo, Hari
Konversi Vol 13, No 1 (2024): April 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i1.17946

Abstract

Increased demand for LNG compels Indonesia to import to meet these needs. Substituting LNG with alternative fuel emerges as a strategy to reduce LPG imports. One such alternative can be used for LPG substitution is Dimethyl Ether. Dimethyl ether is a colorless compound possesses a heating value of 30,5 MJ/kg and an energy equivalency with LPG ranging between 1,56 – 1,76. Dimethyl ether can be directly synthesized from synthetic gas produced through natural gas reforming. Production of synthetic gas from natural gas employs the tri-reforming method which integrating steam reforming, dry reforming, and partial oxidation methods in a single reactor offering optimal energy utilization advantages and minimal environmental impact. Dimethyl ether production from synthetic gas is using direct synthesis method, combining methanol synthesis and dehydration in a single reactor providing high conversion advantages compared to indirect synthesis method. Simulation was carried out using process simulator program ASPEN Plus V11. Based on the simulation results, dimethyl ether yield and selectivity is 99.62%.
ZnO/fly ash catalyst for producing biodiesel from kapok seed (Ceiba pentranda) oil Novantri, Decky Achmad; Innarta, Yahya Dwi Adhitya; Somawiharja, Yohaness; Chern, Jiang-Min; Asri, Nyoman Puspa
Konversi Vol 13, No 1 (2024): April 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i1.15410

Abstract

The quantity of fossil fuels has decreased every year due to increasing energy consumption, thereby requiring alternative renewable energy sources such as biodiesel from kapok seeds. Basically, making biodiesel needs a catalyst. Catalysts are classified into two types based on their phase: homogeneous and heterogeneous. This research employed a ZnO heterogeneous catalyst with fly ash support. It investigated the optimal mole ratio of catalyst and kapok seed oil as well as the optimal catalyst dose to produce the best biodiesel yield. The methodology in this study consisted of ZnO preparation, fly ash preparation, ZnO/fly ash catalyst synthesis, and biodiesel production by the transesterification reaction process. The research variables included the dose of catalyst (wt% oil) of 3, 4, 5, 6, and 7 and the mole ratios of oil to methanol of 1:9, 1:12, 1:15, 1:18, and 1:21. The results of this study indicated that the best catalyst dose was 5% with a biodiesel yield of 58%. Meanwhile, the variable molar ratio of oil to methanol got the highest yield of 65% at 1:8. Therefore, a zinc oxide catalyst with fly ash as support had great potential to produce biodiesel from kapok seed oil.Keywords: Biodiesel; Kapok Seed Oil; ZnO; Fly ash; Yield
Characteristics of PB 260 clone rubber coagulated with natural coagulants: type of Averrhoa Achmad, Feerzet; Deviany, Deviany; Yuniarti, Reni; Fikrah, Faizatul; Az-Zahra, Syifa; Qarimah, Akhlatul; Marlina, Titi; Tambunan, Yonathan Marasi; Rahmadini, Gustia; Damayanti, Damayanti; Suhartono, Suhartono; Suharto, Suharto
Konversi Vol 13, No 1 (2024): April 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i1.18724

Abstract

The aim of this research was to determine the properties of the PB 260 clone rubber using the Averrhoa type coagulant. The natural coagulants used in this study were Averrhoa bilimbi and Averrhoa carambola. The latex used was 150 ml of PB 260 clone rubber with a concentration of 100% natural coagulant of 75 ml and 2% formic acid. The rubber properties that were tested were Po, PRI, DRC, ash content, dirt content, volatile matter content and Mooney viscosity. This research also uses a special treatment in the form of centrifugation speed. The higher the centrifugation speed, the higher the pH value of the natural coagulant and the lower the H+ ion value, which accelerates the coagulation time of the latex. In natural coagulant extract, the highest values of Po, PRI, DRC, ash content, dirt content and Mooney viscosity were obtained at 0 rpm for Averrhoa bilimbi extract with values of 40%, 94.17%, 32.83%, 0, 32%, 0.038% and 77 MU. Meanwhile, in the test for volatile matter content, the highest value was found in Averrhoa carambola at 5000 rpm with a value of 0.23%.
The ability of the Ni/Al2O3 catalyst in the CO2 methanation process in terms of variations in CO2 flow rate and catalyst Parega, Sultan; Junaidi, Robert; Nugroho, Didiek Hari; Niawanti, Helda
Konversi Vol 13, No 2 (2024): OKTOBER 2024
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v13i2.20235

Abstract

Carbon dioxide (CO2) is one of the biggest contributors to the greenhouse effect. Based on International Energy Agency (IEA) data, global emissions of carbon dioxide (CO2) from burning energy and industrial activities will reach 36.8 billion tons in 2022. The increase in emissions in 2022 will mainly come from burning coal and fuel oil (Fuel Oil). Carbon dioxide emissions from coal rose 1.6% while fuel oil emissions increased 2.5%. One effort to reduce carbon dioxide emissions is to convert carbon dioxide into methane gas (CH4) which can be used as fuel. This research aims to produce methane gas from carbon dioxide using Ni/Al2O3 catalyst treatment and varying CO2 flow rates. In this research, CO2 was used as a raw material with a Ni/Al2O3 catalyst and Zn metal. Based on the research results, the highest conversion yield of methane gas was 49.23% with a variation of 0.05 L/minute with Ni_R4 catalyst treatment

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