Eksergi最新文献

{"title":"Mass Transfer Coefficient of Extraction of Anthocyanin from Mangosteen Peel (Garcinia mangostana L.) with Ethanol-HCl as Solvent","authors":"Zubaidi Achmad, Faizah Hadi, S. Kholisoh","doi":"10.31315/e.v19i3.8008","DOIUrl":"https://doi.org/10.31315/e.v19i3.8008","url":null,"abstract":"Anthocyanin is a natural pigment that causes the purple skin of the mangosteen fruit. This study aimed to observe the effect of temperature, stirring time, and ethanol concentration in ethanol–HCl solvent on anthocyanins produced from the mangosteen peel extraction process and determine the value of its mass transfer coefficient. The laboratory work was conducted with mangosteen peel powder extracted with ethanol solvent containing 1% HCl solution using an extraction apparatus set. The mangosteen rind is cleaned and then mashed until it passes the size of -60+80 mesh. Then 50 g of mangosteen rind powder was put into a three-neck flask along with ethanol solution with various concentrations of 55%, 65%, 75%, 85%, and 95%, each containing 1% HCl. Extraction was carried out at various stirring times of 3, 4, 5, 6, and 7 hours with temperature variations of 30, 40, 50, 60, and 70oC. Each product was distilled at a temperature of <60oC. Anthocyanin content were analyzed by spectrophotometric method. The results showed that the optimum conditions at the extraction temperature of 50oC with stirring time for 4 hours and 95% ethanol concentration in ethanol–HCl solvent with anthocyanin content obtained of 9,8377.10-4 (g anthocyanin/g solvent) and kC of 0,00781 g/(cm2.hour).","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49568913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potency of Alluvial Mineral of Luk Ulo River with XRD and AAS in Kebakalan Village Kebumen","authors":"E. Nursanto, Afroza Pratiwi, Eddy Winarno, B. Sugiarto, R. Mirahati","doi":"10.31315/e.v19i3.7826","DOIUrl":"https://doi.org/10.31315/e.v19i3.7826","url":null,"abstract":": Based on petrographic data, XRD, and fluid inclusions, it was interpreted that the quartz veins associated with low sulfide in Karangsambung area underwent 2 stages of system change from mesothermal system to epithermal system. This showed the potential mineral contained in the material, especially in the Luk Ulo River where there were alluvial deposits. To determine the mineral and material composition contained in alluvial material in Luk Ulo River, Kebakalan Village, AAS and XRD were used. This research was limited only to testing Au, Ag, and Cu from 2 samples, namely sample A for sand and sample B for rock. XRD results on samples A and B showed that quartz (SiO 2 ) had the highest percentage (30-50%) compared to other minerals. While the results of the AAS tests showed that the highest Au and Ag contents were in sample B and Cu in sample A with total of 19.30 g/ton Au, 8.67 g/ton Ag, and 62.88 g/ton Cu. Meanwhile, the lowest total Au and Ag were in sample A and Cu was in sample B which amounted to Au 11.32 g/ton, Ag 2.77 g/ton, and Cu 34.86 g/ton.","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69281842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption Equilibrium of Methylene Blue By Activated Carbon From Post-Anthesis Male Flower Palm Oil Waste","authors":"Yuli Ristianingsih, Indriana Lestari, Alit Istiani","doi":"10.31315/e.v19i3.8055","DOIUrl":"https://doi.org/10.31315/e.v19i3.8055","url":null,"abstract":": Methylene blue (MB) is wastewater from the textile industry. This dye is difficult to degrade naturally because it has a benzene group in its chemical chain. There are several ways to reduce waste, one of the economical ways is by using adsorption. In this study, MB was adsorbed using activated carbon from post-anthesis male flower palm oil (PAMF) waste which was activated using potassium hydroxide (KOH). The adsorption process was carried out at various temperatures (30, 40, and 50℃). The results showed that the addition of a KOH activator could increase the sorption capacity of methylene blue by 25.64%. The optimum temperature is suitable for the adsorption process of methylene blue with activated carbon of PAMF waste activated by KOH at a temperature of 30℃ with an adsorption capacity of 58.4793%. The adsorption equilibrium mechanism was studied using two types of adsorption isotherm models, namely the Langmuir and Freundlich models. Based on the data obtained, the MB adsorption process on activated carbon was compatible with the Freundlich model an R 2 of 0.9557.","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49491275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving Stability of Anthocyanin Extracted from Ipomoea batatas by Co-pigmentation","authors":"Rachma Tia Evitasari, G. Budiarti","doi":"10.31315/e.v19i3.7660","DOIUrl":"https://doi.org/10.31315/e.v19i3.7660","url":null,"abstract":"Public awareness of the dangers of using synthetic dyes has started to boost the prestige of natural dyes. The limitation of natural dyes is one of the causes of the limited use of natural dyes commercially. This research utilized purple sweet potato (Ipomoea batatas L.) as a source of anthocyanins. The purpose of this study was the stabilization of anthocyanins from purple sweet potato through the co-pigmentation process. The first stage is the extraction of natural anthocyanin dyes from purple sweet potatoes using the microwave-assisted method, then stabilization of anthocyanins through a co-pigmentation process with variations in the addition of arabic gum, Fe-Alginate, and catechins at various concentrations as Total Anthocyanin Content (TAC), and stability test. The higher the concentration value of the co-pigmenting agent added to the extract, the higher the color shift, indicated by a decrease in the TAC value. The best copigmentation was obtained with green tea containing catechin concentration of 0.01 ml green tea/20 ml extract. with a TAC value of 0.1499 mg/L. Stabilization test against storage, co-pigmentation with catechins in green tea gave the best stability. While the stability against heating and oxidation, co-pigmentation with gum arabic will stabilize the condition of anthocyanin extracts.","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49095303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy Audit of Flouresen Lights at School Building C III Floor Politeknik Negeri Semarang","authors":"S. Supriyo, M. Margana, Wiwik Purwati W, S. Suwarti, M. Mulyono","doi":"10.32497/eksergi.v18i3.3890","DOIUrl":"https://doi.org/10.32497/eksergi.v18i3.3890","url":null,"abstract":"<p dir=\"ltr\"><span>Energy audit is very necessary to calculate the level of energy consumption of a building or buildings. The research includes the amount of energy consumption based on the initial energy audit and detailed energy audit as well as saving opportunities based on conditions in the field. Based on the initial energy audit, the value of the Energy Consumption Intensity (IKE) is 0.699 kWH/m2month, while in the detailed audit the IKE value is 0.935 kWH/m2month. Based on the results of a detailed energy audit, the lighting measurement of 325 lux still meets the requirements for a classroom with a standard between 250 lux to 500 lux.</span></p><div><span><br /></span></div><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script>","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42115837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Analysis of Windings and Vector Groups in 20/0.4 kV Distribution Transformers at CV. Centrado Prima","authors":"Taopik Hidayat, Brainvendra Widi Dionova, Sinka Wilyanti, M. N. Mohammed","doi":"10.32497/eksergi.v18i3.3765","DOIUrl":"https://doi.org/10.32497/eksergi.v18i3.3765","url":null,"abstract":"Turn ratio test is a comparison test of the number of secondary turns with the primary turns on the transformer. The turns ratio and group vector testing is one of the routine transformer tests. This test generally uses the Transformer Turns Ratio (TTR) test tool, the test equipment used sometimes experiences technical and non-technical problems so a comparative test method is needed to get a good analysis. The research method used is observational research and literature study, namely analyzing the transformer to be studied by conducting TTR testing in two ways, namely testing with test equipment and three-phase low voltage sources, aiming to obtain a very good level of accuracy. The test results were analyzed and compared with theory and calculations, with reference to the IEC 60076-1 standard. The results of the comparison of windings and group vectors using TTR 100 test equipment and a 3-phase low voltage source (TVR) show the same conclusions as the results of the analysis, where the first transformer sample is in normal condition and meets the requirements. SPLN D3.002-1:2007 or IEC Standard 60076-1. While the second sample transformer is in an abnormal condition in the W winding where the difference value is above 0.5%.<script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script>","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42754435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biogas Desulfurization Using Iron Gram Waste Machining Practicum Process at The Department of Mechanical Engineering, Politeknik Negeri Semarang","authors":"Nanang Apriandi, W. Widyaningsih, M. Margana, M. Surindra, S. Supriyo, Nadia Tasya Ayu Luthfiana","doi":"10.32497/eksergi.v18i3.3785","DOIUrl":"https://doi.org/10.32497/eksergi.v18i3.3785","url":null,"abstract":"<p class=\"Abstract\">The important matter about biogas as an alternative energy source was the presence of hydrogen sulfide (H₂S) which is very corrosive. The biogas desulfurization process was absolutely necessary to reduce the risk of damage to the equipment. For small-scale applications, the selection of the type of adsorbent became important to reduce additional costs. One alternative material that can be used was iron gram waste. The aim of this study was to investigate the use of iron gram waste resulting from the machining practicum process at the Department of Mechanical Engineering, Politeknik Negeri Semarang as an alternative material for making adsorbents. Iron gram waste was processed into Iron (III) Oxide (Fe₂O₃) and Iron (III) Hydroxide (Fe(OH)₃), formed into billets with an average billet mass of 250 gr. The performance test of the adsorbent in the biogas desulfurization process was carried out under conditions of variation in the flow rate of biogas feed 1, 2, and 3 liters per minute, and the volume of biogas purified in one process was 50 liters. As a result, the most optimum performance was obtained in the test with a feed biogas flow rate of 1 liter/minute, with a percentage reduction in H₂S levels contained in the biogas by an average of 82,56%.</p><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script>","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45735947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monitoring of iot-based Wind and Solar Hybrid Power Plants for Agricultural Irrigation Systems","authors":"B. Prasetiyo, W. Widyaningsih, Yusuf Dewantoro H, S. Suwarti","doi":"10.32497/eksergi.v18i3.3892","DOIUrl":"https://doi.org/10.32497/eksergi.v18i3.3892","url":null,"abstract":"<p dir=\"ltr\"><span>The use of renewable energy, one of which is </span><span>Hybrid</span><span> Power Plants  (PLTH). The PLTH used in this study is a wind and solar power plant. To keep the plant from being damaged and prevent a decrease in tool performance, PLTH was developed based on the</span><span> Internet of Things </span><span>(</span><span>IoT</span><span>).  </span><span>IoT </span><span>will later monitor the performance of the plant.  In this study using the ESP32 TTGO SIM800L microcontroller, the sensors used were DC voltage sensors, current sensors (ACS712), wind speed sensors (</span><span>anemometers</span><span>), wind direction sensors (</span><span>wind vanes</span><span>), and water flow sensors.  The research began with designing the relationship between components, working on monitoring and programming systems on software, installing outdoor sensors and installing monitoring systems, and ending with data observations.   The results  obtained on the observation of data, the best error percentage values  are presented by various sensors with values less than 6%.</span></p><div><span><br /></span></div><br /><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script><script id=\"stacks-wallet-provider\" type=\"text/javascript\" src=\"chrome-extension://ldinpeekobnhjjdofggfgjlcehhmanlj/inpage.js\"></script>","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45826037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of the Use of NaOH and KOH Activators in the Manufacture of Activated Carbon from Cassava Peel (Manihot utilissima)","authors":"Mitha Puspitasari, Wibiana Wulan Nandari, Faizah Hadi","doi":"10.31315/e.v19i2.7245","DOIUrl":"https://doi.org/10.31315/e.v19i2.7245","url":null,"abstract":": Cassava (Manihot utilissima) is a staple food beside rice and corn for Indonesian people. Cassava peel is a waste of cassava processing agroindustries such as tapioca flour industry, fermentation industry, and staple food industry. This waste contains a fairly high carbon element of 59,31%. Cassava peel has the potential to be used as raw material for activated carbon because of its high carbon content. Activated carbon production involved some steps such as preparing raw materials, carbonization, activation, neutralization, and analysis of water content, ash, iodine number, and analysis of the pore surface area of activated carbon. Activated carbon was activated using NaOH and KOH with concentrations of 0.1; 0,2; 0,3; 0,4; and 0,5N. The results showed that activated carbon which activated with 0,4N NaOH and 0,5N KOH provided the closest parameter with SNI 06-3730-1995 standard. The use of NaOH activator can increase the surface area of activated carbon compared to KOH activator.","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42879753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilization of Nanochitosan as Adsorbent of Mercury (Hg) in Gold Ore Processing Waste","authors":"Nadhifa Aliyya Himawan, H. Darmokoesoemo, Totok Ardiarto, A. Prasetya, Badrud Tamam Ibnu Ali","doi":"10.31315/e.v19i2.6862","DOIUrl":"https://doi.org/10.31315/e.v19i2.6862","url":null,"abstract":"Mercury pollution in gold ore processing wastewater can cause environmental and health problems. A large amount of mercury pollution causes neurological disease, paralysis, loss of sense of taste, irregular speech, and death. One effective method to reduce mercury amount in the environment is adsorption. Adsorption performance is affected by several factors such as surface area of material, deacetylation degree (DD), and adsorption condition, which is indicated by contact time and mercury concentration. Nanochitosan is used in this research. Effect of deacetylation degree (85%; 87%; 95%), contact time (30;60;90;120 minutes), and variation of mercury concentration (5;10;15;20;25;30 ppm) on adsorption performance was investigated in this research. Nanochitosan in this research is characterized by FTIR, SEM-EDX, BET-BJH, and pH PZC. AAS measures adsorption performance in this research. The result shows that nanochitosan, which has the best adsorption performance, is nanochitosan with a deacetylation degree of 95%, at a contact time of 60 minutes, and mercury concentration is 15 ppm.","PeriodicalId":30703,"journal":{"name":"Eksergi","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46713625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}