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METANA
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Articles 6 Documents
Search results for , issue "Vol 15, No 2 (2019): Desember 2019" : 6 Documents clear
Adsorption of Sulphur in Biogas by Activated Carbon Derived From Mangrove Fruits (Rhizopora stylosa) as Solid Residue of Natural Dyes Extraction Paryanto, Paryanto; Wibowo, Wusana Agung; Saputra, Nandika Aji; Setyawati, Rosana Budi
METANA Vol 15, No 2 (2019): Desember 2019
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1187.308 KB) | DOI: 10.14710/metana.v15i2.24424

Abstract

Hydrogen sulfide (H2S) is considered as impurity in biogas. H2S could react to form sulfur dioxide (SO2) and sulfuric acid (H2SO4) during the burning process. The corrosive property of these compounds possibly cause damage the power plant system. Overcoming this problem, activated carbon impregnated with KOH has been proven to work very well in adsorbing H2S. On the other hand, mangrove fruits pulp residue from the natural dyes extraction process has not utilized. Mangrove (Rhizopora stylosa) fruits contain about 50% fixed carbon which is possibly made as activated carbon. The purposes of this research were to determine the adsorption efficiency of H2S in biogas using activated carbon derived from mangrove fruits residue and to determine isotherm equilibrium constants for adsorption. The small scale adsorption devices consist of cooler, flow stabilizer, flow regulator, flow meter and column adsorber. At certain flow rate, biogas was sampled in every 10 minutes and then analyzed using portable H2S gas analyzer.  Temperatures of biogas entered the adsorption column were in the range of 33-34oC. The optimum biogas flow rate was 4 liter per minute (lpm) for 250 grams (16 cm of height) of activated carbon. We found the adsorption efficiency was decreased by time and still reached 79.6% for 50 minutes contact time. Based on coefficient of correlation value (R2) on isotherm model, Langmuir model is more suitable for the H2S adsorption of biogas in this study. We found the Langmuir equilibrium constant k was 0.033 and maximum adsorption capacity (x/m)max was 0.284 mg/mg.
Pembuatan dan Karakterisasi Komposit dari Styrofoam Bekas dan Serat Ijuk Aren Purbasari, Aprilina; Darmaji, Timothius Adrian Christantyo; Sary, Cindy Nella; Kusumayanti, Heny
METANA Vol 15, No 2 (2019): Desember 2019
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (791.957 KB) | DOI: 10.14710/metana.v15i2.25794

Abstract

Komposit merupakan gabungan dari dua atau lebih bahan yang menghasilkan efek sinergis. Komposit dapat dibuat dari polimer sebagai matriks dan serat alam sebagai bahan penguat. Pada penelitian ini komposit dibuat dari styrofoam bekas dan serat ijuk aren. Styrofoam merupakan salah satu jenis polimer yang sulit terdegradasi secara alami, sedangkan serat ijuk aren merupakan serat alam yang mudah diperoleh di Indonesia. Pembuatan komposit dilakukan dengan alat hot press pada berbagai perbandingan massa styrofoam dan serbuk ijuk aren (10:90; 20:80; 30:70; 40:60; dan 50:50). Karakterisasi komposit yang dihasilkan meliputi uji kekuatan mekanik, kerapatan, daya serap air, mikrostruktur, dan gugus fungsional. Komposit mempunyai kekuatan mekanik tertinggi sebesar 90,26 kgf/cm2 pada perbandingan massa styrofoam dan serbuk ijuk aren 30:70. Semakin tinggi kandungan styrofoam dalam komposit maka kerapatan komposit akan semakin meningkat dan daya serap air komposit semakin menurun. Komposit mempunyai struktur yang homogen dan gugus fungsional yang berasal dari styrofoam dan serat ijuk aren.Composite is a combination of two or more materials that produce a synergistic effect. Composite can be made from polymers as matrices and natural fibers as reinforcing agents. In this study, composite were synthesized from used styrofoam and sugar palm fiber. Styrofoam is one type of polymer that is difficult to degrade naturally, whereas sugar palm fiber is a natural fiber that is easily obtained in Indonesia. Composite synthesis was done using hot press equipment at various mass ratio of styrofoam to sugar palm fiber powder (10:90; 20:80; 30:70; 40:60; and 50:50). Characterization of obtained composites covered tests of mechanical strength, density, water absorption, microstructure, and functional groups. Composite had the highest mechanical strength of 90.26 kgf/cm2 at the mass ratio of styrofoam to sugar palm fiber powder of 30:70. The increase of the styrofoam content in composite caused the increase of composite density and the decrease of composite water absorption. Composite had homogeneous structure and functional groups derived from styrofoam and sugar palm fiber.  
Filtrasi Ampas Jahe Menggunakan Filter Press Yulifianti, Ade Lina; Eristi, Bella; Puspita, Mawar; Handayani, Dwi
METANA Vol 15, No 2 (2019): Desember 2019
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (971.068 KB) | DOI: 10.14710/metana.v15i2.25086

Abstract

Ampas jahe hasil buangan proses industri jamu masih mengandung sari jahe. Pengolahan ulang dengan pelarutan dan penyaringan dengan plate and frame filter press dapat dilakukan untuk mengisolasinya. Penggunaan variabel konsentrasi umpan 0,2 kg/liter, 0,4 kg/liter, dan 0,6 kg/liter.  Menggunakan  tekanan tetap 2 kg/cm2 dan laju alir 5,66x10-11 m/s2, dihitung nilai tahanan spesifik ampas (α), tahanan ampas (Rc), tahanan medium filter (Rm) untuk mengetahui efesiensi kinerja alat filter press. Proses filtrasi dilakukan secara batch. Hasil perhitungan menunjukkan  nilai α, Rc, dan Rm tertinggi pada konsentrasi 0,6 kg/L yaitu α (4,98x106 m/kg), Rc (1,35x108 m-1), Rm (3,79x1011 m-1). Efektivitas produk yang dihasilkan diketahui melalui pengukuran konsentrasi sari jahe pada hasil filtrat. Pengujian konsentrasi menggunakan centrifuge dan analisa Total Suspended Solid (TSS). Hasil analisa centrifuge menyatakan bahwa semakin besar konsentrasi umpan, maka semakin besar pula konsentrasi produk. Konsentrasi sari jahe tertinggi yang didapat 6,67%, terdapat pada variable konsentrasi umpan 0,6 kg/liter. Begitu pula dengan uji TSS, konsentrasi umpan 0,6 kg/liter menghasilkan TSS terbesar yaitu 277 mg/l. Ginger pulp from the process of industrial herbs still contain ginger juice. Reprocessing ginger pulp with dissolving and filtering with plate and frame filter press can done to isolate it. Use feed variable concentration 0.2 kg/liter, 0.4 kg/liter, and 0.6 kg/liter.  Fixed pressure used is 2 kg/cm2 and flow rate use 5.66x10-11 m/s2, will calculated the specific prisoner value of the pulp (α), Prisoner of Pulp (Rc), Prisoner of medium filter (Rm) to know the efficiency of the performance of filter press. Filtration process is done in batches. The results of the calculation show the highest value of α, Rc, and Rm at concentrations 0.6 kg/liter are α (4.98x106 m/kg), Rc (1.35x108 M-1), Rm (3.79x1011 M-1). Effectiveness of the resulting products is known through measurements of ginger juice concentrations in filtrate results. Concentration testing using centrifuge and Total Suspended Solid (TSS) analysis. Result of centrifuge analysis states that the greater  concentration of feed, that the greater the concentration of product. The highest concentrations of ginger juice gained 6.67%, there is a variable concentration feed 0.6 kg/liter. Similarly, the test of TSS, the concentration feed 0.6 kg/liter resulted in the largest TSS 277 mg/l. 
Karakterisasi Katalis CaO dan Uji Aktivitas pada Kinetika Reaksi Transesterifikasi Minyak Kedelai Pratigto, Setiarto; Istadi, Istadi; Wardhani, Dyah Hesti
METANA Vol 15, No 2 (2019): Desember 2019
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1178.735 KB) | DOI: 10.14710/metana.v15i2.25106

Abstract

Penelitian ini akan mengkaji kinetika reaksi transesterifikasi minyak kedelai dengan metanol menggunakan katalis CaO dengan parameter rasio mol reaktan terhadap konversi metil ester yang digunakan untuk menentukan persamaan kecepatan reaksi. Katalis CaO digunakan untuk reaksi transesterifikasi karena memiliki kekuatan basa yang tinggi, ramah lingkungan, kelarutan yang rendah dalam metanol. Kinetika reaksi untuk reaktor batch dihitung saat reaksi berlangsung berdasarkan rejim surface area limited yang menentukan. Tujuan penelitian ini untuk mengetahui bentuk persamaan kecepatan reaksi transesterifikasi minyak kedelai dan metanol menggunakan katalis CaO menurut metode differential reactor. Penelitian dilakukan dengan reaksi transesterifikasi minyak kedelai dan metanol dengan katalis CaO dengan variabel bebas perbandingan mol reaktan. Hasil penelitian mengemukakan metanol teradsorpsi di permukaan katalis dan trigliserida tidak teradsorpsi di permukaan katalis menunjukkan mekanisme reaksi katalitik Eley-Rideal. Persamaan kecepatan reaksi dapat digunakan dalam perancangan reaktor, sehingga hubungan antara konversi trigliserida menjadi biodiesel dengan kebutuhan berat katalis dan volume reaktor yang diperlukan dapat diprediksi. This study will examine the kinetics of the transesterification reaction of soybean oil with methanol using a CaO catalyst with the parameters of the mole ratio of reactants to the conversion of methyl esters used to determine the reaction velocity equation. CaO catalyst is used for transesterification reaction because it has high base strength, environmentally friendly, low solubility in methanol. The reaction kinetics for a batch reactor are calculated when the reaction takes place based on a decisive surface area limited regime. The purpose of this study was to determine the shape of the speed equation for the transesterification of soybean oil and methanol using a CaO catalyst according to the differential reactor method. The research was carried out with the transesterification reaction of soybean oil and methanol with a CaO catalyst with a free variable ratio of reactant moles. The results of the study revealed that methanol adsorbed on the surface of the catalyst and triglycerides not adsorbed on the surface of the catalyst showed an Eley-Rideal catalytic reaction mechanism. The reaction speed equation can be used in reactor design, so the relationship between the conversion of triglycerides to biodiesel with the required catalyst weight and the reactor volume required can be predicted.
Model Sistem Monitoring pH dan Kekeruhan pada Akuarium Air Tawar berbasis Internet of Things Tadeus, Dista Yoel; Azazi, Khasnan; Ariwibowo, Didik
METANA Vol 15, No 2 (2019): Desember 2019
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1110.623 KB) | DOI: 10.14710/metana.v15i2.26046

Abstract

Ikan hias dan vegetasi air memiliki rentang toleransi terhadap nilai parameter lingkungan. Parameter tersebut hendaknya senantiasa diawasi demi kelangsungan hidupnya. Internet of Things (IoT) telah dimanfaatkan sebagai sistem monitoring dan otomasi parameter lingkungan ikan dan vegetasi air namun sistem ini membutuhkan biaya yang tinggi. Tujuan penelitian ini adalah mengembangkan suatu model sistem monitoring berbasis IoT berbiaya rendah untuk memberikan informasi parameter pH dan kekeruhan air setiap saat kepada pemilik ikan hias. Sistem ini dibangun menggunakan komponen opensource dan sensor berbiaya rendah. Data monitoring digunakan untuk mengaktifkan aktuator berupa filter air. Filter akan aktif apabila tingkat kekeruhan air sudah melebihi batas kekeruhan yang ditentukan. Pengujian kekeruhan air aquarium menunjukkan saat kekeruhan mencapai 3000 ntu pukul 14.12 pompa aktif dan filter bekerja sampai kekeruhan berada pada nilai 498 ntu pada pukul 17.00 dan pompa mati secara otomatis. Nilai pH dan kekeruhan air berhasil ditampilkan dengan baik di aplikasi Blynk pada ponsel. Hasil pengujian menyimpulkan bahwa sistem monitoring yang dikembangkan telah berhasil diimplementasikan dengan baik.  Ornamental fish and aquatic vegetation have a tolerance range of environmental parameter values. These parameters should always be monitored for survival. Internet of Things (IoT) has been utilized as a monitoring and automation system for environmental parameters of fish and aquatic vegetation, but this system requires high costs. The purpose of this study is to develop a low-cost IoT-based monitoring system model to provide information on pH parameters and water turbidity at any time to ornamental fish owners. This system is built using opensource components and low-cost sensors. Monitoring data is used to activate the actuator in the form of a water filter. The filter will active if the turbidity level of water has exceeded the specified turbidity limit. The aquarium water turbidity test showed that when the turbidity reached 3000 ntu at 14.12 the pump was active and the filter worked until the turbidity was at 498 ntu at 17.00 and the pump automatically shut down. The pH value and the turbidity of the water were successfully displayed in the Blynk application on the cellphone. The test results concluded that the monitoring system developed was successfully implemented. 
Bioplastik Berbasis Galaktomanan Hasil Ekstraski Ampas Kelapa Dengan Campuran Polyvinyl Alkohol Sari, Nofita; Mairisya, Maudy; Kurniasari, Riska; Purnavita, Sari
METANA Vol 15, No 2 (2019): Desember 2019
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (993.211 KB) | DOI: 10.14710/metana.v15i2.24892

Abstract

Penelitian ini bertujuan untuk mendapatkan kondisi optimum yang meliputi luas permukaan dan jumlah solven pada proses ekstraksi galaktomanan dari ampas kelapa terhadap yield yang dihasilkan dan mendapatkan kondisi optimumpada proses pembuatan bioplastik yang meliputi jumlah sorbitol dan waktu pencampuran terhadap karakteristik bioplastik yang meliputi ketebalan, ketahanan air, kuat tarik, elongasi, waktu degradasi dan morfologi.Bioplastik merupakan plastik yang dapat diuraikan oleh mikroorganisme dalam waktu yang singkat, sehingga lebih ramah lingkungan dibandingkan plastik konvensional.Bioplastik terbuat dari bahan polimer alami seperti pati, selulosa atau lemak.Penelitian pembuatan bioplastik ini berbasis dari galaktomanan ampas kelapa dan PVA. Galaktomanan merupakan polimer alami yang memiliki kemampuan membuat lapisan film.Polyvinyl alkohol (PVA) merupakan polimer sintetik namun memiliki sifat mudah larut dalam air sehingga dapat digunakan sebagai bahan campuran pembuatan bioplastik. PVA juga mampu meningkatkan elastisitas dan kuat tarik bioplastik. Penelitian ini menghasilkan bioplastik dengan ketebalan terbaik 0,18 mm dan prosentase ketahanan air tertinggi 74,76%. Tensile strength bioplastik terbaik dengan nilai 7,55 MPa, sedangkan prosentase elongation terbaik 46,81%. Bioplastik pada penelitian ini memiliki titik leleh (MP) 120°C dan terdegradasi sempurna dalam 24 jam. This study aims to obtain optimum conditions which are including surface area and amount of solvent in the galactomannan extraction process from coconut pulp to the produced yield and obtaining the optimum conditions in the bioplastic manufacturing process which are included the amount of sorbitol and mixing time of the bioplastic characteristics including thickness, water resistance, tensile strength, elongation, degradation time and morphology. Bioplastics are plastics that can be decomposed by microorganisms in a short time, making them more environmentally friendly than conventional plastics bioplastics made from natural polymer materials such as starch, cellulose, or fat. The research in making bioplastics was based on galactomannan coconut pulp and PVA. Galactomannan is a natural polymer that can make film layers. Polyvinyl alcohol (PVA) is a synthetic polymer but has properties that are soluble in water so it can be used as a mixture of bioplastics. PVA is also able to increase the elasticity and strong pull of bioplastics. This study produced bioplastics with the best thickness of 0,18mm and the highest percentage of water resistance in 74,76%. The best bioplastic tensile strength at 7,55 MPa value, while the best percentage of elongation 46,81%. Bioplastics in this study had a melting point (MP) of 120 ° C and were degraded correctly in 24 hours.

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