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Jurnal Sains dan Teknologi Reaksi
Published by Politeknik Negeri Lhokseumawe
ISSN : 1693248X     EISSN : 25491202     DOI : http://dx.doi.org/10.30811/jstr
Core Subject : Science, Education, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Education Engineering Materials Science & Nanotechnology
Jurnal Sains dan Teknologi Reaksi atau boleh disingkat dengan nama JSTR, berfokus pada banyak Aspek Teknik Kimia, seperti: Teknik Reaksi Kimia, Teknik Kimia Lingkungan, Energi Fosil dan Terbarukan, serta Sintesis dan Pengolahan Material.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 318 Documents
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CHARACTERIZATION OF BIODEGRADABLE POLYURETHANE POLYMER BASED ON BENTONITE-CHITOSAN HYBRID PALM SA, Sabiila Yasara; Syafruddin, S; Rihayat, Teuku
Jurnal Sains dan Teknologi Reaksi Vol 21, No 02 (2023): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v21i02.4942

Abstract

Corrosion problems that often occur cause various damages and losses. The coating process has the advantage of being able to protect the metal surface from environmental influences that result in corrosion of the metal. The innovation of combining Polyurethane with Bentonite-Chitosan filler is able to make the polymer have better corrosion resistance. This study aims to see the effect of mixing between Polyurethane and Bentonite-Chitosan filler. The sample formulation used is polyurethane with variations of bentonite and chitosan 1%, 3%, 5%, 7%, 9%. The addition of Bentonite-chitosan filler affects the mechanical properties of the material. Characterization with the addition of Bentonite and Chitosan produces a polymer that has good thermal stability and good corrosion resistance. Test result Fourier Transform Infrared(FT-IR) there are functional groups NH, CH, C=O. Based on test resultsThermogravimetric Analysis(TGA) samplePolyurethane with modified bentonite 9%/chitosan 9% w/w has the best thermal stability among other samples where the sample starts to degrade (on set) at 419.22(oC) and stops degrading (end set ) at 521.94 (oC) with a weight loss of -31.156%. Polyurethane samples with 1% bentonite/chitosan 9% w/w modification had lower thermal stability where the sample started to degrade (onset) 312.21 (oC) and stopped degrading (end set) at 391.09 (oC) with a weight loss of -55.729 %. The results of the morphological test using the SEM tool show that the chitosan chains dispersed well into the bentonite interlayer. The corrosion test showed that the addition of bentonite and chitosan affected the corrosion rate, the greater the composition of bentonite and chitosan, the lower the corrosion rates. the best sample with a ratio of Polyurethane/Bentonite/Chitosan 9:9% w/w experienced the smallest corrosion rate of 5.08mpy and a mass loss of 0.1 gram.Keywords: Biodegradable, Corrosion, Polyurethane, Bentonite, Chitosan
ANALYSIS OF THE EFFECT OF PRESSURE AND AIR FLOW RATE ON THE PURITY OF NITROGEN GAS PRODUCTS PRODUCED BY THE PRESSURE SWING ADSORPTION (PSA) METHOD AT PT. ARUN GAS PERTA Jalaluddin, J; Yunus, M; Elfiana, E
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5522

Abstract

ABSTRACTNitrogen is a basic compound in the chemical industry. Nitrogen is an inert gas compound so it is suitable for various applications covering various aspects of manufacturing, processing, handling and shipping chemicals. The aim of this research is to analyze the influence of impurities, pressure and air flow rate on the purity of nitrogen gas products produced using the Pressure Swing Adsorption (PSA) method, then carry out a comparison or simulation of actual field data with Aspen Adsorption V.10. The research method used is descriptive qualitative, the data in this research is field operational data and data collection techniques are carried out periodically through data log sheets. From the research results, it was found that Purity in October to November 2023 on October 5 and 27 was 99.98%, with a flow of 52.2 Nm3/h, while for November there was 98.01% (purity) with flow 105.0 Nm3/h. And after carrying out simulations using Aspen Adsorption V.10 and varying the input data, Purity was obtained at 99.98%, 99.97%, 99.91% with a flow of 100 Nm3/h, 150 Nm3/h, 200 Nm3/h or 0, 4461 kmol/s, 0.6692 kmol/s, 0.8992 kmol/s in Aspen Adsorption V.10 applications.Keywords: Nitrogen, Pressure Swing Adsorption (PSA), Aspen Adsorption, Carbon Molecular Sieve (CMS) 
THE EFFECT OF ADDING CHITOSAN ON THE MECHANICAL PROPERTIES OF ECO-FRIENDLY PLASTICS BASED ON PLA/PCL Alfatasya, Dinda; Suryani, S
Jurnal Sains dan Teknologi Reaksi Vol 21, No 02 (2023): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v21i02.4814

Abstract

ABSTRACTResearch into making eco-friendly plastic has been developed because it is environmentally friendly and renewable. In this research, eco-friendly plastic was made from Polylactic Acid (PLA) and Polycaprolactone (PCL) with the addition of chitosan as a filler. The aim of this research is to study and determine the effect of mixing variations in PLA/PCL/chitosan composition on the mechanical properties of eco-friendly plastic using a hot press at a temperature of 200 0C for 1 hour. The PLA/PCL variations are 2/8 g, 3/7 g, 5/5 g, 7/3 g and 8/2 g while the chitosan composition is 0.2 g, 0.3 g, 0.4 g, 0, 5 g and 0.6 g. The characteristics of eco-friendly plastic can be seen through biodegradation tests, tensile strength tests, elongation tests, functional group tests and plastic film morphology tests. The results of the characterization of eco-friendly plastic with optimal performance are a composition of PLA/PCL/Chitosan 8/2/0.6 grams which produces 38.8% degradation percentage, a tensile strength value of 42.53 MPa with a composition of PLA/PCL/Chitosan 8 /2/0.4 grams, elongation percentage of 6.96% with a PLA/PCL/Chitosan composition of 8/2/0.2 grams. Meanwhile, the functional groups contained are the N – H, C – H, C = O and C – O groups. The results of the identification of functional groups show that no new functional groups are formed, but only a mixing process without any reaction in the constituent materials. Based on the results of the morphology test, it shows that the sample has a smooth surface. However, there is still chitosan that does not dissolve because the mixing process is not homogeneous.Keywords: Chitosan, Polycaprolactone (PCL), Polylactic Acid (PLA)
THE EFFECT OF EMULSIFIER SPAN 60 (Sorbitan Monostearate) ON THE HOMOGENEITY PROPERTIES OF LOTION GEL MADE Virgin Coconut Oil (VCO) AND ALOE VERA Nurhaliza, Siti; Yunus, M; Adriana, A
Jurnal Sains dan Teknologi Reaksi Vol 21, No 02 (2023): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v21i02.4952

Abstract

ABSTRACT Making lotion from Virgin Coconut Oil (VCO) and Aloe Vera to which an emulsifier has been added requires antimicrobial ingredients, because the water phase facilitates the growth of microorganisms. The presence of methyl paraben preservative is very important in oil-in-water emulsions, because the shelf life of the product will last longer. This research aims to determine the effect of span 60 on homogeneity properties. The physical properties of the lotion include homogeneity test, pH test, viscosity test and specific gravity test based on SNI-16-3499-1996. The experimental process was carried out with varying weights of span 60 (sorbitan monostearate) 1 mg, 3 mg, 5 mg, 7 mg, methyl paraben with varying weights of 1.5 mg, 2 mg, 2.5 mg, 3 mg and a stirring time of 21 minutes. With the liquid phase and the heated oil phase.0.95- 1.05 g/ml. Keywords: Virgin Coconut Oil (VCO), Aloe Vera, Emulsifier, Span 60 (Sorbitan Monostearate), Methyl Paraben, Homogeneity.
TESTING CHEMICAL ZINC PHOSPHATE BASE AS A CORROSION INHIBITOR ON CARBON STEEL IN THE CORROSION MEDIA OF COOLING WATER, SEA WATER AND PDAM WATER Sariadi, S; Kenady, Rengga Rahmat; Irwan, I; Zaini, Halim
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5620

Abstract

Zinc phosphate base corrosion inhibitor which aims to determine the effectiveness of the inhibitor to provide protection to carbon steel against the rate of corrosion, with variations in inhibitor concentration at 0, 20, 40 and 60 ppm.This research uses the weight loss method and studies the performance of zinc phosphate base chemical inhibitors in the mediacooling water, sea water and PDAM waterThis is done by carrying out SEM (Scanning Electron Microscopy) testing. The type of steel specimen used in the research is Carbon Steel and deepCorrosion media are cooling water, sea water and PDAM water.The addition of zinc phosphate base carbon steel inhibitor is effective in reducing the corrosion rate of carbon steel in PDAM water and sea water. in sea water media without inhibitors, a drastic reduction in the corrosion rate was seen from 119.0457 mpy to 1.7754 mpy and in PDAM water media without inhibitors, a drastic decrease in the corrosion rate was seen from 18.5873 mpy to 3.4163 mpy, after adding inhibitors with a concentration of 60 ppm. The efficiency of the zinc phosphate base inhibitor in cooling water corrosion media was 30.262% at a concentration of 40 ppm and a soaking time of 20 days. Keywords :Inhibition efficiency, Corrosion Inhibitors, Corrosion in sea water, Corrosion in cooling water, Corrosion Rate, Zinc Phosphate base.
DISTILLATION OF ESSENTIAL OILS FROM PATCHOULI LEAVES USING SOLAR ENERGY (PHOTOVOLTAIC) AS A HEATING SOURCE Prayogi, Muhammad Akbar; Rihayat, Teuku; Zaini, Halim
Jurnal Sains dan Teknologi Reaksi Vol 21, No 02 (2023): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v21i02.4815

Abstract

Currently, the use of the sun as renewable energy is very effective. Solar Cells or commonly called Photovoltaic systems are components used to absorb heat from sunlight which is converted into electrical energy. This photovoltaic technology is very well implemented in Indonesia because of the tropical climate and long exposure to sunlight. Of the many types of essential oils, one of the most prominent in Indonesia is patchouli oil. Currently, essential oil refining still uses energy sources that can be scarce at any time and are less environmentally friendly. In this research, we tried to design a distillation device using solar cells to produce electricity which will later be used as a heating source. The highest yield obtained was 2.60% at a drying time of 32 hours and a distillation time of 420 minutes and the lowest yield obtained was 0.94% at a drying time of 0 hours and a distillation time of 300 minutes. From the results of analysis using GC-MS, it shows that the chemical compounds identified include 4,7-Methanoazulene, Seychellene, and several other compounds. Based on the GC-MS results, patchouli alcohol was 37.18% and 4,7-Methanoazulene was 2.78%. According to International Market Standards, the patcholi alcohol content must be higher than 30%, therefore this material meets the Indonesian National Standard (SNI).Keywords : Solar Cell, Patchouli Oil, Distillation Equipment, Indonesian National Standard
DEVELOPMENT OF CHITOSAN MODIFIED POLYURETHANE COMPOSITE AS A BASE MATERIAL FOR ANTIBACTERIAL COATING PAINT Wahyuni, Sri; Rihayat, Teuku; Syafruddin, S
Jurnal Sains dan Teknologi Reaksi Vol 21, No 02 (2023): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v21i02.5255

Abstract

ABSTRACTPolyurethanes are generally made from petroleum-based polyols, but the current state of petroleum is depleting. The availability of petroleum, which is currently decreasing, encourages other parties to look for new alternatives. One alternative that can be used is palm oil. Technological developments that continue to increase are now also a reference for the development of antibacterial polyurethane coating paints which are carried out by adding another filler, namely chitosan. This study aims to determine the effect of variations in the weight of chitosan as an antibacterial agent and to determine the effect of the ratio of polyol and TDI on the quality of the paint analyzed through functional group analysis with Fourier Transform Infra Red (FTIR), morphological analysis of Surface Scanning Electron Microscopy (SEM), Heat resistance test with Thermo Gravimetry Analyzer (TGA), and Bacterial activity test. The analysis process was carried out with variations in the weight of chitosan (0; 2; 3; 4; 5; 6) % w/w and variations in the ratio of polyol and TDI (50:50) %; (40:60)%; (45:55)%. The test results showed that the best polyurethane paint was the variation in the ratio of polyol and TDI 50:50% with 6%w/w chitosan filling. This is because the more chitosan added, the better it will be in inhibiting bacterial activity, and the more polyols, the better the paint quality. The test results showed that the best polyurethane paint was the variation in the ratio of polyol and TDI 50:50% with 6%w/w chitosan filling. This is because the more chitosan added, the better it will be in inhibiting bacterial activity, and the more polyols, the better the paint quality. The test results showed that the best polyurethane paint was the variation in the ratio of polyol and TDI 50:50% with 6%w/w chitosan filling. This is because the more chitosan added, the better it will be in inhibiting bacterial activity, and the more polyols, the better the paint quality.Keywords: Chitosan, Composites, Polyols, Polyurethanes, TDI
THE EFFECT OF UTILIZING IE KULOH SIRA, IE ASAM SUNTI, AND CORNELA ON THE CHARACTERISTICS OF SILK TOFU Salmyah, S; TA, Cut Fatmawati; Haziri, Ahmad Abrar; Rahmawati, Cut Aja
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5707

Abstract

ABSTRACTSilken tofu is a type of tofu that has a soft and compact texture. Ie kuloh sira and ie acid sunti can be used as coagulants. The lack of this coagulant results in a tofu texture that is not compact. Therefore, cornstarch is added to the making of silken tofu to improve the quality of the resulting silken tofu texture. This study aims to determine the effect of the type and concentration of coagulant and cornstarch concentration on the characteristics of silken tofu and the shelf life of silken tofu. This research method uses the Response Surface Method (RSM) and the organoleptic method. Coagulant concentration (0.5%, 1%, 1.5%, 2%, 2.5%) and cornstarch concentration (5%, 10%, 15%, 20%, 25%). The results obtained for silken tofu with coagulant ie kuloh sira and cornstarch obtained the optimal value, namely at concentrations of ie kuloh sira 2% and cornstarch 10% producing a protein content of 8.45%, texture 4.5 mm/sec. The concentration of ie kuloh sira and cornstarch did not affect the color and aroma of silken tofu, but it did affect the taste of silken tofu. Meanwhile, silk tofu with coagulant ie acid sunti and cornstarch obtained the optimal value, namely at a concentration of 1.5% ie acid sunti and 15% cornstarch producing a protein content of 7.57%, texture 4 mm/sec. The concentration of ie acid sunti and cornstarch has an effect on the color of silken tofu, but has no effect on the aroma and taste of silken tofu. The shelf life of silken tofu with coagulant ie kuloh sira and ie asam sunti only lasted 15 hours at room temperature. Meanwhile, those stored in the refrigerator can last for 3 days with a coagulant ie kuloh sira and 5 days with a coagulant ie acid sunti. Keywords: silken tofu, namely kuloh sira, namely sunti acid, cornstarch, RSM
DISTILLATION OF ESSENTIAL OILS FROM THE LEAVES AND STEMS OF CITRONELLA (Cymbopogon Winterianus) USING A SOLAR ENERGY-BASED VAPOR DISTILLATION APPARATUS WITH PHOTOVOLTAIC METHOD Hafidh, Muhammad; Rihayat, Teuku; Elwina, E
Jurnal Sains dan Teknologi Reaksi Vol 21, No 02 (2023): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v21i02.4816

Abstract

The photovoltaic method with solar panel modules with a capacity of 100 Wp can absorb heat and convert it into electrical energy up to 100 watts / hour and is used for the citronella oil refining process which requires 57,550 Kj of energy.  By using 4 solar cell panels, within 4 hours the power generated is able to meet these energy needs. Based on the test results of the design of the distillation device using solar cells, the efficiency of energy absorption cannot be absorbed up to 100%, due to the occurrence of lost energy but this can be overcome with a longer absorption time. In testing citronella oil with variations in drying time and distillation time, it was found that the optimum time to produce the highest percentage of citronella oil yield was at a drying time of 18 hours with a distillation time of 6 hours, namely 1.20%. From the laboratory tests produced, citronella oil with variations in drying time and operating time has a density value ranging from 0.8751gr/ml to 0.8831gr/ml and the best GC-MS test results obtained the amount of citronellol in the sample as much as 15.73% and the amount of geraniol as much as 28.57% has met the Indonesian National Standard (SNI) 2385-2006.Keywords: Solar Cell, Photovoltaic, Citronella Oil, Solar Panel
Manufacturing Silage From Field Grass For Cattle Feed Using The Fermentation Method Kiram, Jumadil; Zaini, Halim; Satriananda, S
Jurnal Sains dan Teknologi Reaksi Vol 21, No 02 (2023): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v21i02.5256

Abstract

ABSTRACT Ruminant livestock require forage for growth, reproduction and production. The principle of forage for livestock is that it contains good nutrition and is available throughout the year. One technology for preserving forage is by making silage. Making silage, apart from preserving and minimizing nutrient loss, can also improve feed nutrition. Silage is feed that is preserved through the ensiling process, namely the process of preserving feed or forage using fermentation work under anaerobic conditions (Suadnyana, et al, 2017). In this research, field grass silage was made with the addition of EM4 containing Lactobacillus sp bacteria at different concentrations and varied fermentation times so that making field grass silage is expected to improve the fermentative quality and improve or maintain the nutritional quality of the feed which can be seen from the content. water, protein content, pH, and color. The analysis process was carried out with varying fermentation times of 4, 8, 12, 16 and 20 days and EM4 concentrations of 0.2%, 0.4%, 0.6% and 0.8% (v/w). The test results show that the best silage is with a fermentation time variation of 20 days with an EM4 concentration of 0.6%, 20 days with an EM4 concentration of 0.2%, and 16 days with an EM4 concentration of 0.8%. This is because the longer the fermentation time and the more EM4 added, the better the quality of the silage obtained. Keywords: EM4, Bran, Fermentation, Molasses, Silage

Page 26 of 32 | Total Record : 318

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