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METANA
Published by Universitas Diponegoro
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Articles 8 Documents
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Search results for , issue "Vol 19, No 1 (2023): Juni 2023" : 8 Documents clear
Valorization of red ginger hydrodistillation wastes as foot sanitizers Puntigavere Dante; Efri Mardawati; Riska Surya Ningrum; Awaly Ilham Dewantoro; Munajat Munajat
METANA Vol 19, No 1 (2023): Juni 2023
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v19i1.52666

Abstract

Red ginger is known as one of the medicinnal and aromatic plants that have high value in the form of essential oils. The distillation of red ginger essential oils required large amounts of water, and then most of the water was disposed of as wastewater. This wastewater is known as hydrosol, which still contains a small amount of essential oils and secondary metabolites such as zingiberene and geraniol. These compounds were considered to have the potential to be utilized in cosmetic products such as foot sanitizers. The aim of this study was to evaluate a foot sanitizer product based on red ginger hydrosol that combined with coffee extracts based on its antibacterial activity against Staphylococcus aureus and the physical characteristics of the product. Foot sanitizer was produced in three formulations with different concentration (in percentage) of red ginger hydrosols and coffee extracts consist of F1 (45:25), F2 (35:35), and F3 (25:45). The results showed the F3 formulation provided the largest antibacterial inhibition (2.89±0.60 mm) compared to other formulations. The F3 formulation has a physical characteristics such as coffee scent aroma, a dark brown color, a pH of 5.5, a density of 960.73 kg/m3 and has a weak antibacterial activity. Based on the comparison results with previous studies, the utilization of coffee extracts in red ginger hydrosols-based foot sanitizer needs to be substitued with other natural extracts, especially having a strong antibacterial activity. It should be carried out to increase the potential value of valorizing red ginger hydrosols as foot sanitizer.
Pembuatan Arang Aktif Dari Gambut Hasil Pirolisis Katalitik Dengan Aktivator NaCl Ghiffary Dalf Assaury; Syahda Khairunnisa Ahnaf; Aqiila Tasya Arinanda; Sitti Sahraeni
METANA Vol 19, No 1 (2023): Juni 2023
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v19i1.53234

Abstract

Gambut mengandung senyawa organik seperti hemiselulosa, lignin dan selulosa. Gambut pada bagian atas disebut gambut fibrik dan gambut dapat diolah menjadi arang aktif. Pembuatan arang aktif perlu dilakukan proses karbonisasi dan pada umumnya proses karbonisasi menggunakan metode pirolisis. Tujuan penelitian ini adalah untuk membuat arang aktif dari gambut fibrik dengan menggunakan metode pirolisis katalitik dan aktivasi menggunakan NaCl yang dapat memenuhi standar arang aktif menurut SNI 06-3730-1995 dari parameter kadar air, kadar abu, volatile matter dan daya serap iod. Gambut diproses secara pirolisis katalitik dengan mencampurkan bahan baku gambut dan katalis zeolit alam (1% dari bahan baku) pada suhu 500oC selama 120 menit. Selanjutnya 10 gram arang diaktivasi menggunakan variasi konsentrasi aktivator NaCl 10%, 15%, 20%, 25%, 30% selama 180 menit menggunakan perbandingan 1:10 (berat/volume) dan kecepatan pengadukan 350 rpm. Hasil optimum diperoleh pada NaCl konsentrasi 15%, dengan kadar air 4,71%, kadar abu 24,35%, volatile matter 5,20%, fixed carbon dan daya serap I2 774,14 mg/g. Hasil analisa kadar air dan volatile matter telah memenuhi standar SNI serta daya serap I2 telah memenuhi standar SNI untuk konsentrasi aktivator NaCl 15%. Namun kadar abu semua variasi konsentrasi aktivator masih belum memenuhi standar SNI. 06-3730-1995.  Peat contains organic compounds such as hemicellulose, lignin and cellulose. Peat at the aspart is called fibric peat, can be processed into activated charcoal. The manufacture of activated charcoal requires a carbonization process such as the pyrolysis method. The purpose of this study is making activated charcoal from fibric peat using catalytic pyrolysis and activation method using NaCl to meet activated charcoal standards according to SNI 06-3730-199. Peat is processed by catalytic pyrolysis using natural zeolite catalysts (1% of raw materials) at a temperature of 500oC for 120 minutes. Furthermore, 10 grams of charcoal were activated using variations in NaCl activator concentrations of 10%, 15%, 20%, 25%, 30% for 180 minutes using a ratio of 1:10 (weight/volume) and a stirring speed of 350 rpm. Optimum results were obtained at 15% NaCl concentration, with a moisture content of 4.71%, ash content of 24.35%, volatile matter of 5.20%, fixed carbon of 65.74% and absorption of I2 774.14 mg/g. The results of the analysis of water content, volatile matter, and the absorption capacity of I2 has met the SNI standard for a 15% NaCl activator concentration. However, the ash content of all variations in activator concentrations still does not meet SNI 06-3730-1995.
Optimalisasi Demulsifier pada Pemurnian Minyak Mentah Duri Fajar Kholistiono; Mohamad Endy Yulianto
METANA Vol 19, No 1 (2023): Juni 2023
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v19i1.49967

Abstract

Pada proses pemurnian minyak mentah di area Duri dilakukan pada fasilitas stasiun pengumpul umum. Stasiun pengumpul ini melakukan proses pemurnian minyak bumi rata – rata 20.000 barel per hari dan air 250.000 barrel per hari. Pada proses pemurnian ini dibutuhkan demulsifier untuk membantu proses pemurnian. Konsumsi demulsifier saat ini sangat besar, dengan rata – rata pemakaian sebesar 100ppm perhari. Hal ini menimbulkan biaya operasional yang cukup besar dalam hal pemakaian demulsifier pada proses pemurnian minyak bumi dibanding jumlah produksi minyak bumi yang dihasilkan. Untuk itu akan dilakukan penelitian dengan tujuan mengoptimalisasi pemakaian demulsifier tanpa mengubah kualitas produk hasil pemurnian minyak bumi. Pada rencana penelitian ini jumlah galon demulsifier akan dikonversikan menjadi ppm terhadap jumlah minyak bumi yang diproduksi. Percobaan akan dilakukan dengan metode bottle test dengan analisa data menggunakan factorial design. Percobaan dilakukan dengan menggunakan variasi variabel dari demulsifier, temperatur dan retention time. Variabel tersebut antara lain demulsifier akan diuji pada 80 ppm dan 90 ppm; temperatur akan diuji pada 160 °F dan 170 °F; retention time akan diuji pada 4 jam dan 5 jam. Dengan percobaan ini diharapkan dapat ditemukan kombinasi temperatur, retention time dan jumlah demulsifier paling optimum untuk menghasilkan minyak bumi yang baik. Tujuan akhir setelah ditemukan kombinasi tersebut maka diharapkan pemakaian demulsifier akan menurun sehingga dapat menurunkan biaya pembelian demulsifier untuk proses pemurnian minyak bumi.     The process of refining crude oil in the Duri area is carried out at public collection station facilities. This collection station performs the process of refining crude oil - an average of 20,000 barrels per day and 250,000 barrels of water per day. In this purification process, a demulsifier is needed to assist the purification process. Consumption of demulsifiers is currently very large, with an average usage of 100ppm per day. This causes operational costs that are quite large in terms of using a demulsifier in the petroleum refining process compared to the amount of oil produced. For this reason, research will be carried out with the aim of optimizing the use of demulsifiers without changing the quality of refined petroleum products. In this research plan, the number of gallons of demulsifier will be converted to ppm for the amount of petroleum produced. The experiment will be carried out using the bottle test method with data analysis using a factorial design. The experiment was carried out using a variable variation of the emulsifier, temperature and retention time. These variables include the demulsifier that will be tested at 80 ppm and 90 ppm; temperatures will be tested at 160°F and 170°F; retention time will be tested at 4 hours and 5 hours. With this experiment it is hoped that the optimum combination of temperature, retention time and amount of demulsifier can be found to produce good petroleum. The ultimate goal after this combination is found is that it is hoped that the use of demulsifiers will decrease so that it can reduce the cost of buying demulsifiers for the process of refining petroleum.
Pretreatment of Used Cooking Oil Using Avocado Seed Adsorbent for Biodiesel Production Preparation Nasriadi Dali; Seniwati Dali; Armadi Chairunnas; Hilda Ayu Melvi Amalia; Sri Ayu Andini Puspitasari
METANA Vol 19, No 1 (2023): Juni 2023
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v19i1.51797

Abstract

Used cooking oil (UCO) can be used as raw material for biodiesel production, but its free fatty acid (FFA) content is still quite high, so it is necessary to do pretreatment in the form of an adsorption process to reduce FFA levels. This study aims to determine the optimum conditions for the adsorption process and determine FFA levels of UCO before and after pretreatment. The adsorbent used is avocado seed activated charcoal, because it has a surface area of 19.62 m2/g. The larger the surface area of the adsorbent material, the greater the adsorption capacity of the adsorbent. Optimization of the UCO adsorption process includes variations in adsorbent mass (6, 8, 10 g), adsorbent particle size (60, 100, 140 mesh), contact time (2, 6, 10 hours), and temperature (60, 80, 100oC). The results showed that the optimum conditions for adsorption of UCO were obtained at mass (10 g), particle size (100 mesh), contact time (6 h), and temperature (80oC). This condition can reduce the FFA content of UCO by 71.64% (w/w), from 5.29% (w/w) to 1.50% (w/w). The FFA content of UCO [1.50% (w/w)] produced after pretreatment was qualified as a raw material for the preparation of biodiesel production through the transesterification stage.
Optimasi Proses Deasetilasi Kitin menjadi Kitosan dari Selongsong Maggot menggunakan RSM Rendy Ardianto; Rizka Amalia
METANA Vol 19, No 1 (2023): Juni 2023
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v19i1.50480

Abstract

Maggot (Hermetia illucens) adalah organisme yang berasal dari telur Black Soldier Fly (BSF) dan salah satu organisme pembusuk karena mengonsumsi bahan-bahan organik untuk bertahan hidup. Di Indonesia budidaya Black Soldier Fly (BSF) semakin diminati belakangan ini. Dalam budidaya Black Soldier Fly selalu menghasilkan limbah berupa selongsong Black Soldier Fly yang masih belum banyak digunakan yaitu sekitar 2/5 dari total produksi. Saat ini selongsong maggot belum banyak dimanfaatkan. Padahal, selongsong maggot berpotensi menjadi bahan baku alternatif dalam produksi kitosan.. Dengan demikian, Black Soldier Fly (BSF) ini merupakan sumber baru biopolimer kitin yang menarik untuk diteliti dan digunakan dalam berbagai aplikasi. Untuk produksi kitin sendiri ada 3 tahap yaitu meliputi proses demineralisasi, deproteinasi, dan depigmentasi. Untuk mengubah kitin menjadi kitosan dilakukan proses deasetilasi. Nilai derajat deasetilasi sangat mempengaruhi kualitas kitosan yang dihasilkan.  Faktor-faktor utama yang menentukan keberhasilan proses deasetilasi adalah suhu dan waktu ekstraksi. Oleh karena itu, penelitian ini dilakukan untuk mengetahui optimasi produksi kitosan berbasis selongsong maggot dengan variasi waktu dan suhu. Optimasi suhu dilakukan pada variasi suhu deasetilasi 60oC, 70oC, 80oC dan variasi waktu 8, 10, dan 12 jam dengan metode Response Surface Metodhology (RSM). Derajat deasetilasi tertinggi diperoleh saat suhu 84,14214°C dengan waktu 10 jam menghasilkan 93,03823%   Maggot (Hermetia illucens) is an organism that comes from Black Soldier Fly (BSF) eggs and is one of the decaying organisms because it consumes organic materials to survive. In Indonesia, the cultivation of the Black Soldier Fly has been increasingly in demand lately. In Black Soldier Fly cultivation, it always produces waste in the form of Black Soldier Fly casings which are still not widely used, which is around 2/5 of the total production. Currently maggot casings have not been used much. In fact, maggot sleeves have the potential to become alternative raw materials in chitosan production. Therefore, the Black Soldier Fly (BSF) is an interesting new source of biopolymer chitin for research and use in various applications. For the production of chitin itself there are 3 stages which include the process of demineralization, deproteination, and depigmentation. To convert chitin into chitosan, a deacetylation process is carried out. The degree of deacetylation greatly affects the quality of the chitosan produced. The main factors that determine the success of the deacetylation process are temperature and extraction time. Therefore, this research was conducted to determine the optimization of chitosan production based on maggot sleeves with variations in time and temperature. Temperature optimization was carried out at various deacetylation temperatures of 60oC, 70oC, 80oC and time variations of 8, 10 and 12 hours using the Response Surface Methodology (RSM) method. The highest degree of deacetylation was obtained at 84.14214°C for 10 hours to produce 93.03823%
Pengaruh Daya Microwave Terhadap Pembuatan Biodiesel Dengan Katalis Fly Ash/Na2O Menggunakan Iradiasi Microwave Syarifuddin Oko; Citra Natali Kasih Mattanggung; Muhammad Naufal Aulia; Reza Firdaus
METANA Vol 19, No 1 (2023): Juni 2023
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v19i1.53241

Abstract

Minyak goreng yang telah digunakan berkali-kali akan mengalami penurunan kualitas sehingga tidak layak lagi untuk digunakan kembali. Saat ini telah ditemukan metode baru untuk pengolahan biodiesel ramah lingkungan dari limbah minyak goreng yakni dengan menggunakan gelombang mikro. Tujuan dari penelitian ini untuk mengetahui pengaruh variasi daya alat microwave terhadap rendemen, densitas, viskositas kinematik, dan kadar air biodiesel yang dihasilkan berdasarkan Standar Nasional Indonesia Nomor 7182:2015 Tentang Biodiesel. Proses dilakukan menggunakan reaksi esterifikasi dan transesterifikasi untuk pembentukan metil esternya dengan bantuan katalis fly ash/Na2O. Pembuatan katalis dilakukan dengan melakukan impregnasi pada fly ash batu bara menggunakan NaOH dengan proses pemanasan di dalam furnace selama 1 jam pada temperatur 750 oC. Daya alat gelombang mikro yang digunakan adalah 180, 300, 450, 600, dan 800 watt dengan waktu reaksi selama 4 menit dan katalis fly ash/Na2O sebanyak 15 gram. Pembuatan biodiesel menggunakan acuan Standar Nasional Indonesia Nomor 7182:2015 Tentang Biodiesel, dengan rincian syarat mutu biodiesel berupa densitas biodiesel pada 40 oC berada pada rentang 850 – 890 kg/m3, viskositas kinematik pada 40 oC berada pada rentang 2,3 – 6,0 mm2/s (cSt), dan kadar air dan sedimen maksimal sebanyak 0,05 % volume, sehingga karakteristik biodiesel yang dihasilkan dari seluruh variasi daya di luar standar biodiesel yang berlaku.   Cooking oil that has been used many times will experience decrease in quality and no longer suitable for compsumtion. Currently, a new method has been invented for processing enviromentally friendly biodiesel from waste cooking oil by using microwaves. The purposes of this research are to determine effect of varying the microwave power on the rendement, denisty, kinematic viscosity, and water residue of the biodiesel based on Indonesian National Standard Number 7182:2015 About Biodiesel. Using esterification and transesterification reaction to form methyl ester and using fly ash/Na2O as catalyst. Catalyst was prepared by impregnation coal fly ash with NaOH with heating process using furnace for 1 hour at 750 oC. Microwaves power that used was 180, 300, 450, 600, and 800 watts with 4 minutes reaction time and 15 grams fly ash/Na2O catalyst. The production of biodiesel refers to Indonesian National Standard Number 7182:2015 About Biodiesel, with details of biodiesel quality requirements density at 40 oC in the range of 850 – 890 kg/m3, kinematic viscosity at 40 oC in the range of 2,3 – 6,0 mm2/s (cSt), and maximum water residue is 0,05 % volume, so that the characteristics of the biodiesel from all power variations still out of the standards. 
Pengaruh Jumlah Pengemulsi pada Pembuatan Cat Emulsi Berbasis Bahan Alami Kasein dari Susu Sapi Sari Purnavita; Cyrilla Oktaviananda; Elisa Rinihapsari; Priyo Wibowo; Yosef Bintang Satya Primahendra
METANA Vol 19, No 1 (2023): Juni 2023
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v19i1.52473

Abstract

Produksi susu sapi yang melimpah tidak diikuti dengan permintaan yang tinggi dari  masyarakat sehingga banyak produk susu sapi yang tidak termanfaatkan. Susu sapi yang masih segar maupun yang sudah rusak memiliki kandungan kasein yang cukup tinggi. Kasein termasuk polimer alami sehingga dapat dimanfaatkan sebagai bahan utama pada pembuatan cat emulsi. Pada pembuatan cat emulsi, faktor yang harus diperhatikan adalah kestabilan emulsi. Maka, penelitian ini bertujuan untuk mengetahui pengaruh jumlah pengemulsi (1 gram, 2 gram, 3 gram, dan 4 gram) yang digunakan terhadap karakteristik cat yang meliputi ukuran partikel, waktu kering, viskositas, daya rekat, dan kekerasan. Hasil uji statistik (Uji F) menunjukkan bahwa jumlah pengemulsi memiliki pengaruh terhadap karakteristik cat yang meliputi ukuran partikel, waktu kering, viskositas, daya rekat, dan kekerasan. Hasil penelitian dengan menggunakan uji statistik (Uji F) menunjukkan bahwa jumlah pengemulsi berpengaruh nyata terhadap karakteristik viskositas, ukuran partikel, waktu kering, dan tingkat kekerasan, serta jumlah pengemulsi berpengaruh sangat nyata terhadap karakteristik daya rekat cat. Cat emulsi berbasis kasein dan kapur tohor dengan penambahan bahan pengemulsi CMC sebanyak 4 gram memiliki kualitas yang terbaik, yaitu nilai kekerasan 4 H, daya rekat 97,5%, waktu kering 38,5 menit, ukuran partikel 8,75 mikron, dan viskositas 450 d.Pa.s.   The abundant cow's milk production is not followed by high demand from the public so that many cow's milk products are not utilized. Cow's milk that is still fresh or that has been spoiled has a fairly high casein content. Casein is a natural polymer so it can be used as the main ingredient in the manufacture of emulsion paints. The factor that must be considered in the manufacture of emulsion paint is the stability of the emulsion, thus this study aims to determine the effect of the amount of emulsifier (1 gram, 2 gram, 3 gram, and 4 gram) used on the paint characteristics which include particle size, dry time, viscosity, adhesion, and hardness. Statistical test results (Test F) showed that the amount of emulsifier has an influence on the characteristics of the paint which includes particle size, drying time, viscosity, adhesion, and hardness. The results of the study using statistical tests (Test F) showed that the amount of emulsifier had a significant effect on the characteristics of viscosity, particle size, dry time, and level of hardness, and the amount of emulsifier had a very significant effect on the characteristics of paint adhesion. Casein and quicklime based emulsion paint with the addition of 4 grams of CMC emulsifier has the best quality, namely 4 H hardness, 97.5% adhesion, 38.5 minutes dry time, 8.75 micron particle size, and 450 viscosity. d.Pa.s.
Pembuatan Pewarna Alami dari Ekstrak Daun Alpukat dengan Penambahan Tawas, Kapur Sirih, dan Tunjung Susi Lestari; Edy Supriyo
METANA Vol 19, No 1 (2023): Juni 2023
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v19i1.54292

Abstract

Pewarnaan tekstil dapat dilakukan dengan menggunakan pewarna dari bahan sintesis dan alami.   Pada dasarnya pewarna alami lebih aman digunakan dibandingkan dengan pewarna sintesis. Sedikitnya  pencemaran merupakan salah satu keunggulan penggunaan pewarna alami. Daun alpukat berpotensi digunakan sebagai bahan pewarna alami karena mengandung tanin yang cukup besar. Tanin dapat menghasilkan zat warna cokelat dan kecokelatan pada kain. Akan tetapi, penggunaan pewarna alami kurang diminati oleh masyarakat karena hasil pewarnaan yang kurang mencolok jika dibandingkan dengan pewarna sintesis. Dalam penelitian ini dilakukan inovasi pembuatan pewarna alami tekstil dengan variasi penambahan zat fiksasi warna. Tujuan penelitian ini untuk meningkatkan variasi warna pewarna alami yang dihasilkan dan meningkatkan ketahanan luntur warnanya. Terdapat empat sampel dengan variabel bebas yang berbeda. Variabel bebas yang digunakan yakni jenis zat fiksasi yang ditambahkan dalam sampel. Sampel F0 merupakan sampel kontrol tanpa penambahan zat fiksasi, Sampel F1 dengan penambahan zat fiksasi tawas 0,05 M, sampel F2 dengan penambahan zat fiksasi kapur sirih 0,05 M, dan sampel F3 dengan penambahan zat fiksasi tunjung 0,05 M. Sampel hasil fiksasi warna dilakukan pengujian absorbansi serta ketahanan luntur. Dari penelitian ini diperoleh hasil terbaik  Textile coloring can be done using dyes from synthetic and natural materials. Basically, natural dyes are safer to use than synthetic dyes. Little pollution is one of the advantages of using natural dyes. Avocado leaves have the potential to be used as natural dyes because they contain a large amount of tannins. Tannins can produce brown and brown dyes on fabrics. However, the use of natural dyes is less attractive to the public because the coloring results are less conspicuous when compared to synthetic dyes. In this research, an innovation was made in the manufacture of natural textile dyes with variations in the addition of color fixation agents. The purpose of this research is to increase the color variations of the natural dyes produced and to increase their color fastness. There were four samples with different independent variables. The independent variable used is the type of fixing agent added to the sample. Sample F0 was a control sample without the addition of fixing agent, Sample F1 with the addition of 0.05 M alum fixative, F2 sample with the addition of 0.05 M whiting fixing agent, and F3 sample with the addition of 0.05 M tunjung fixative.Samples resulting from color fixation were tested for absorbance and fastness. From this study, the best results were obtained on sample F1 (alum fixation) with an absorbance of 0.6914 and dye absorption of 0.1150 mol/L and the results of the color fastness test on a scale of 4 (good).

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