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METANA
Published by Universitas Diponegoro
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Articles 220 Documents
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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.
TEKNOLOGI PRODUKSI PUPUK ORGANIK CAIR DARI LIMBAH SAMPAH RUMAH TANGGA DI KELURAHAN LEMPONGSARI, KODYA SEMARANG DENGAN KOMPOSER EM-4 Wahyuningsih Wahyuningsih; Edy Supriyo
METANA Vol 9, No 01 (2013): Juli 2013
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (270.528 KB) | DOI: 10.14710/metana.v9i01.7205

Abstract

Abstract In Semarang limited landfill waste,new problems.If problems not handled and managed properly,an increase of waste that occur each year could shorten justify the air.In addition,the waste can the quality of natural resources,causing floods,and cause some diseased. Research to be conducted has several specific objectives,as follomposer EM-4.Minimizing the volume of waste in Semarang environment develop a network tool composter for organic fertilizer production of large-scale environmental and examine the addition of decomposers EM-4 the formation of humus to improve the productivity of organic fertilizer in environmentally friendly, operating condition optimization weathering process household waste using waste decomposer EM-4. Composter network of productivity environmentally friendly is expected to replace the function of inorganic fertilizers Research results:the best is on addition EM-4 8 ppm,with the following results:value ratio C/N 14,77;P2O5 1,24%;K2O 0,42%  SNI: ratio C/N 10-20 ;0,1% min P2O5 ;0,2%min K2O Keyword: EM-4 composer,liquid compost organic,organic waste
PRODUKSI FORMULASI INSEKTISIDA CAIR BENTUK EMULSIFIER CONCENTRATE YANG EFEKTIF GUNA MEMBASMI NYAMUK AEDES AEGYPTI DALAM USAHA MENCEGAH PENYAKIT DEMAM BERDARAH Supriyo, Edy; Abidin, Zainal; Nugraheni, Nugraheni; Wahyuni, Sri
METANA Edisi Khusus Februari 2011
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (6779.819 KB) | DOI: 10.14710/metana.v0i0.1662

Abstract

Abstract   Liquid pesticide formulation in the form of emulsifier concentrate (EC) is more preferable because it does not form clogging and blocking in the tools and precipitating that harden. Based on fired capacity in the whole pesticide formulation industry, about 25 % produce emulsifier concentrate. In the emulsion formulation, the important point is unite insoluble matter become a homogeny and stable formulation for long period. The selection of emulsifier type is very important because it is influenced by quality and EC formulation stability. Result formula very good is 20 % propoxure; 5 % Malathion; 5 %; agrisol ; 20 % DBS; 45 % Xyline dan 5 % additive (%w/w), concentration affection test 0.025% v/v for thinner solvent in 20 strain aedes aegypti mosquitoes at Semarang killed on 2 hours = 4 mosquitoes, 4 hours = l0 mosquitoes, 6 hours = 16 mosquitoes and on 8 hours all mosquitoes had been died. From emulsion stability test, in oil phase and water phase was found terpentine as stable solvent in the emulsion form, with separated oil percentage at concentration 3mg/l about 42%. In water phase emulsion forms micro emulsion with white fog colors in whole concentration 1, 2 and 3 ppm   Keyword: Emulsifier Concentrate
Ekstraksi Pektin Dari Kangkung Darat Menggunakan Pelarut Asam Sitrat Irawan, T. A. Bambang; Prihanto, Antonius
METANA Vol 12, No 1 (2016): Juni 2016
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (940.125 KB) | DOI: 10.14710/metana.v12i1.17510

Abstract

Kangkung tergolong sayur yang sangat populer, karena banyak peminatnya. Di Indonesia kangkung tumbuh subur dan memiliki siklus perkembangan panen yang tiap tahun meningkat. Wawasan tentang pemanfaatan kangkung di masyarakat masih minim. Oleh karena itu untuk menambah wawasan tentang pemanfaatan kangkung di masyrakat, kangkung dapat dijadikan sebagai sumber energi alternatif pembuatan pektin.  Jumlah pektin yang terkandung di dalam kangkung tersebut berkisar 6,71 % per 100 gram kakngkung darat kering. Pektin merupakan polimer dari asam D-Galakturonat yang dihubungkan oleh ikatan ß -1,4 glikosidik. Untuk menguraikan pektin didalam kangkung darat  dapat dilakukan dengan metode ekstraksi dengan menggunakan pelarut asam kemudian ditambahkan etanol kedalam filtrat untuk mengendapkan pektin dan proses terakhir dilakukan pengeringan untuk mendapatkan pektin kering. Penelitian ini dilakukan dengan menambahkan asam sitrat dengan range pH 1,5; 2; 2,5 (sebagai variabel) dan dengan waktu ekstraksi 60, 75, 90 menit (sebagai variable). Hasil penelitian m,enunjukan bahwa pektin terbaik dapat diperoleh pada pH 2 pada waktu proses 75 menit dengan rendemen 3,25%, kadar air 7,14 %, dan kadar metoksil 5,9 %. Extraction of Pectin From Kale Using Citrate Acid Solvent Kale classified as a vegetable is very popular, because many devotees. In  Indonesia kale thrive and have the development cycles of harvest each year is increasing. Insights on the use of kale in the community is still minimal. Therefore, to add knowledge about the use of kale in society, kale can be used as an alternative energy source the manufacture of pectin. Total pectin contained in the swamp around 6.71% per 100 grams of dry ground kakngkung. Pectin is a polymer of D-galacturonic acid linked by ß -1,4 glycosidic bonds. To decipher the pectin in the swamp land can be done by using a solvent extraction method with acid is then added ethanol added to the filtrate to precipitate pectin and final drying process to obtain dry pectin. This research was conducted by adding citric acid to a pH range of 1.5; 2; 2.5 (variable) and the extraction time of 60, 75, 90 minutes (as a variable). M research results, the best enunjukan that pectin can be obtained at pH 2 at runtime 75 minutes with a yield of 3.25%, 7.14% moisture content, and the content of methoxyl 5.9%.
REPAIR OF PROCESS EXTORTION OF CENTRIFUGAL OIL AND ADJUSMENT OF TECHNOLOGY IS PRECISELY UTILIZE AT INDUSTRY CHIPS EMPING GEPUK MELINJO DI KABUPATEN BATANG Abidin, Zainal
METANA Vol 5, No 2 (2007): Desember 2007
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2990.615 KB) | DOI: 10.14710/metana.v5i2.1902

Abstract

Abstract At the industry produce the chips emping gepuk melinjo conventional generally experience of the resistance at process extortion of oil because this process walk gravitationly with extortion time about 0.5 hour. Problems of arising out is oil conten in chips emping gepuk melinio still high about 15 %  is while equipments of extortion of oil which have is not yet can operate in an optimal fashion ( leak is in gravitation with time of 30 minute).  is so that needed by the equipments able to improve ; repair the process extortion of oil in chips emping gepuk melinjo fry. This matter will pursue in improvement of capacities produce the chips emping gepuk melinio. To increase product to be needed modify, equipments of extortion of oil,  so that efiensi production can be boasted up and peaceful for the use it and also improve the chips emping product qualitv gepuk. As according to the clauses released by Departemen Kesehatan, oil content in food stuff fried by is less than 5%. because at high oil rate will quicken the process rancidity at food-stuff. Besides with high oil rate will be able to improve the cholesterol rate in blood. From the result of perception during extortion by centrifugal oil wringer, extortion time about 2 - 3 minute with oil content in chips emping gepuk under or less than 5 %, so that the result of chips emping gepuk yielded by seen drier and will improve the endurance.   Keyword : Chips emping gepuk melinjo, centrifugal wringer,oil rate and extortion time.
Modifikasi Motor Bakar 4 Langkah Bahan Bakar Bensin Menjadi Biogas: Aplikasi Untuk "Engine Test Bed" Wijayanto, Wishnu; Apriyanti, Eny
METANA Vol 14, No 2 (2018): Desember 2018
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (525.732 KB) | DOI: 10.14710/metana.v14i2.21393

Abstract

Biogas  merupakan  salah  satu  bahan  bakar  non  fosil  bersifat  renewable  (terbarukan)  yang  dapat  dijadikan  bioenergi  alternatif. Biogas memiliki konsentrasi gas metana (CH4) yaitu 50–75 %,  gas karbon dioksida (CO2)25–50%, gas nitrogen (N2) 0 - 0,3 %, gas hidrogen (H2) 1-5 %, gas hidrogen sulfida (H2S) 0,1-2 % dan gas oksigen (O2) 0,1-0,5 %. (Hambali, 2007). Untuk dapat menggunakan biogas sebagai bahan bakar motor bakar pada mesin bensin generator 4 langkah 1300 (watt) dilakukan modifikasi pada : kelonggaran katup isap dan buang, injektor venturi pada karburator dan menaikkan rasio kompresi 9,2 – 9,3. Pada pengujian dihasilkan torsi maksimum 4,1 (Nm), Temperatur 490 oC pada pembebanan 1000 (watt).
UPAYA PERBAIKAN SIFAT FISIKOKIMIA TEPUNG UBI KAYU MELALUI PROSES FERMENTASI SAWUT UBI KAYU DENGAN STARTER BAKTERI ASAM LAKTAT LACTOBACILLUS CASEI DAN PEMANFAATANNYA SEBAGAI BAHAN BAKU SNACK TRADISIONAL PILUS DAN ROTI MUFFIN Kusumaningrum, Annisa; Sumardiono, Siswo
METANA Vol 8, No 02 (2012): Desember 2012
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (222.425 KB) | DOI: 10.14710/metana.v8i02.6809

Abstract

Cassava is one of the biggest commodity in Indonesia which is the total amount of its production is 24,080,000 ton/year. This huge amount of cassava can be used as cassava flour so that it could have similar characteristics with wheat flour. Therefore, in this research the cassava is being modified by fermentation method using the lactic acid bacteria starter,i.e Lactobacillus casei. While the cassava grate is being fermented, the enzyme that could destroy the cassava cell is produced by bacteria so it cause the degradation of starch granula. This condition changes of the physiochemical characteristic of cassava flour produced. The purpose of this research determines the best condition from the variables concentration of lactic acid bacteria starter and fermentation time of the cassava grate to physiochemical characteristic of cassava flour. The best conditions of cassava flour is fermentation time of 48 hour and 6% v/v Lactobacillus casei concentration. Physiochemical characteristic of cassava flour best treatment is the swelling power of 14.13, level of expand “pilus” snack 596.399%, baking expansion 2.28 cm /g and hardness of 3 muffin cake was 620.262 gf. Keywords: cassava fermentation, Lactobacillus casei, physiochemical characteristic, fermentation time, concentration of lactic acid bacteria starter
Peningkatan Produksi Garam Beryodium Melalui Aplikasi Alat Pencetak Garam Secara Mekanik Handayani, Dwi; Murni, Murni; Ikhsan, Diyono; Arifan, Fahmi
METANA Edisi Khusus Februari 2011
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4919.381 KB) | DOI: 10.14710/metana.v0i0.1629

Abstract

The salt moulder groups "Muji Rahayu" have a mission for drummed up salt moulders by are very limited, by process technology conventionally. The result of production is salt_powder  which is a gunny_pack then on sale at the prince of low. If it is soled in salt_moulder, the price will increase. Salt moulder form of Instrumentation which it is has incereased quality and sale at the prince salt iodized consumption. However, at the employe moulder machine which is continue, the machine has trouble because it is always related to salt which have a character is corrosive. Therefore, it needs to have a salt_moulder which is simple and easy to be operated by salt-farmer moreover the price is cheap. The salt moulder will work by mechanic and aplication style. Because of the caracter of salt which corrosive, so the contraction which related to salt is made by stainless steel. By the expectation it be able to increase the income of salt_farmers. Keywords : iodized salt, salt moulder
PENGOLAHAN LIMBAH ORGANIK DAN ANORGANIK MENGGUNAKAN KOMBINASI FOTOKATALIS TiO2 DAN SENYAWA ETHYLENEDIAMINETETRAACETIC ACID (EDTA) Sutardjo, F.X. Sulistiyanto Wibowo; Wildan, Achmad; Handyanaputri, Eka Susanti
METANA Vol 11, No 02 (2015): Desember 2015
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (593.318 KB) | DOI: 10.14710/metana.v11i02.14751

Abstract

AbstrakTitanium dioksida (TiO2) adalah senyawa yang sering digunakan pada proses fotokatalisis, untuk lebih meningkatkan aktivitas fotokatalis TiO2 dapat dilakukan dengan kombinasi TiO2 dengan suatu khelat asam etilendiamintetraasetat (EDTA), EDTA ditambahkan untuk mencegah terjadinya rekombinasi electron-hole sehingga aktivitas fotokatalisis dalam mendegradasi senyawa organik dan mereduksi senyawa anorganik lebih efektif dan optimal. Penelitian ini bertujuan untuk mengetahui pengaruh lama penyinaran dan pengaruh penambahan senyawa EDTA pada TiO2 terhadap fotodegradasi amoksisilin dan fotoreduksi ion Cu(II), massa kombinasi TiO2 dengan EDTA yang digunakan adalah 1 : 0, 1 : 1, dan 1 : 2. Sedangkan variasi lama penyinaran  yang digunakan adalah  20,  40, dan  60 menit. Metode yang digunakan untuk mengetahui konsentrasi amoksisilin menggunakan Spektrofotometri UV dan konsentrasi ion Cu(II) menggunakan Spektrofotometri Serapan Atom. Hasil penelitian menunjukan ada pengaruh variasi lama penyinaran dan  penambahan senyawa EDTA pada katalis TiO2 terhadap fotodegradasi amoksisilin dan fotoreduksi ion logam Cu(II). Kondisi optimal lama penyinaran pada proses fotodegradasi amoksisilin dan fotoreduksi ion logam Cu(II) adalah 60 menit dan dengan variasi  TiO2 kombinasi EDTA yaitu 1 : 2, pada konsentrasi tersebut amoksisilin yang terdegradasi sebesar 54,69% dan ion logam Cu(II) yang tereduksi sebesar 47,74%. Kata kunci: Titanium dioksida, Fotokatalis, asam diamintetraasetat (EDTA), ion logam Cu (II), Amoksisillin  Abstract Titanium dioxide (TiO2) is a compound that is often used in the photocatalyst, to increase the activity of TiO2 photocatalyst can be done by a combination of TiO2 with a chelate ethylenediaminetetraacetic acid (EDTA), with added EDTA is expected to prevent the recombination of electron-hole so that the photocatalyst activity in degrading organic compounds and inorganic compounds reduce more effectively and optimally. This study aims to determine the effect of irradiation time and the effect of adding the compound EDTA on TiO2 against photodegradation amoxicillin and photoreduction Cu(II) metal ion, the variation of a combination of TiO2 with EDTA used is 1 : 0,1 : 1 and 1 : 2. While variations of irradiation time used are 20, 40, and 60 minute. The method used to determine the concentration of amoxicillin using UV spectrophotometry and concentration of Cu(II) metal ion using atomic absorption spectrophotometry. The results showed have effected of variations irradiation time  and the addition of EDTA on TiO2 catalyst against photodegradation amoxicillin and photoreduction Cu(II) metal ion. Optimal conditions of irradiation time in the process of photodegradation amoxicillin and photoreduction Cu(II) metal ion is 60 minute and the variation of a combination of TiO2 with EDTA used is 1 : 2, at these concentrations of amoxicillin degraded by 54.69% and the Cu(II) metal ion were reduced by 47.74%. Keywords : Titanium dioxide, Photocatalyst, ethylenediaminetetraacetic acid (EDTA), Cu (II) metal ion, Amoxicillin 
STUDI PENGARUH TEMPERATUR AUSTENITIASI DAN HOLDING TIME PADA PROSES HARDENING BAJA K 460 Suyadi, Suyadi
METANA Vol 3, No 2 (2006): Juli 2006
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/metana.v3i2.1806

Abstract

Abstract on the harcening process of K 460 steel, austenite temperature and holding time plays very important roles in influencing the result of hardening. In this research, austenite tenrperature variatiorrs are 755oc, 770 oc,785oc. 8l5oc, and 840oc with holding time of 5'30',60' and 120'. Then research result indicates that on 755oc. variation of the holding time produce high increase of hardness. For the others temperature need 30' to reach homogeny phase and more 30' holding time make the hardness relative constant. Meanwhile, the impact strength would be varied caused by intemal stress and residual austenite. For statistical analysis with 99oc accuracy, it's found that the effect-of temperature and holding time and it's both interactions make the number of hardness and the impact strength grow significantly.   Key words : hardening, temperature austenite, holding time

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