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PENGARUH KUAT ARUS PADA SISTEM METODA ARUS TERPASANG (Impressed Current Method) (SUATU UPAYA UNTUK MEMPERLAMBAT LAJU KOROSI PADA SALURAN PIPA BAJA) . Suhartana
JURNAL ILMIAH MOMENTUM Vol 4, No 1 (2008)
Publisher : Universitas Wahid Hasyim

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36499/jim.v4i1.628

Abstract

Oksidasi besi atau korosi dan upaya memperlambat lajunya, adalah pertarungan yang tak akan pernah selesai antara peristiwa oksidasi dan upaya pencegahan yang dikemukakan oleh ilmuwan. Banyak cara yang bisa dilakukan untuk memperlambat laju korosi ini. Dalam makalah ini akan diuraikan cara memperlambat laju korosi dengan Metoda Arus Terpasang. Prinsip Metoda Arus Terpasang adalah membuat bahan yang akan dilindungi ditempatkan sebagai katoda, dan bahan lain yang akan dikorbankan ditempatkan sebagai anoda. Dengan kontrol arus kita dapat mendeteksi apakah anoda masih berfungsi atau tidak. Kata kunci: katoda, anoda, dan kontrol arus. Abstract Oxidation of ferrous or corrosion and effort to slow down fast corrosion , is combat which will never finish between oxidized material and preventive effort which told by scientist and engineer. Many way of which would be done to slow down fast corrosion. In this case would be elaborated by the way of slowing down fast of corrosion by Impressed Current Method. Impressed Current Method is to make materials to protect to be to be placed as cathode, and other materials to be sacrificed as anode. With current control we earn to detect do anode have function or not. Keyword: cathode, anode, and current control
Electrocoagulation Method Using Al/Graphite Electrode for Removal Surfactant LAS (Linear Alkylbenzene Sulfonate) Nafisa Khairunisa; Suhartana Suhartana; Damar Nurwahyu Bima
Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Vol 18, No 3 (2021): November 2021
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (442.962 KB) | DOI: 10.14710/presipitasi.v18i3.443-452

Abstract

An increasing number of laundries have caused water contamination by surfactants. One commonly used surfactant is LAS (Linear Alkylbenzene Sulfonate), a material difficult to decompose, polluting the environment. Electrocoagulation was carried out using Al/Graphite electrode, applied to LAS surfactant artistic waste. This study aims to determine the functional ability of the Al/Graphite electrode in reducing surfactant through electrocoagulation. Various variations were carried out, on the voltage parameters (3,6,9,12) Volt; NaCl concentration (0;0.4;0.8;1.2;1.6;2) g/L; pH (3,5,7,9,11) and time (10,20,30,40,50) minutes. To analyze the changes in the sample before and after electrocoagulation, characterization was carried out using a UV-VIS spectrophotometer and FTIR. A kinetic study was conducted to determine the reaction order of electrocoagulation surfactant. Based on a study, removal at condition voltage 9 Volt, initial pH of the solution 9, electrocoagulation time 50 minute, and the addition of NaCl electrolyte 2 g/L, obtained surfactant concentration was 0,785 mg/L with removal efficiency 97,45%. UV-VIS spectra show a decreased absorption at a wavelength of 653 nm. FTIR spectra showed the presence of absorption on the same functional groups, which indicated that most of the surfactant pollutants could be separated from the wastewater through the electrocoagulation process. The second-order reaction was obtained in the surfactant electrocoagulation process.
Electrochemical Peroxidation Method for Reduction of Chemical Oxygen Demand (COD) Carbofuran in Furadan 3GR Pesticides Ayu Sri Wahyuni; Suhartana Suhartana; Damar Nurwahyu Bima
Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Vol 18, No 2 (2021): July 2021
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (631.93 KB) | DOI: 10.14710/presipitasi.v18i2.181-191

Abstract

Carbofuran is a pollutant compound derived from the pesticide Furadan 3GR which is widely used in agriculture. Various methods of carbofuran degradation have been carried out, one of which is the conventional electrochemical method. This study used an electrochemical peroxidation process to degrade Carbofuran in the pesticide Furadan 3GR. This study aims to determine the optimum conditions (time, Na2SO4 concentration, and volume addition of H2O2) for electrochemical peroxidation and to compare the effectiveness of electrochemical and electrochemical peroxidation methods by measuring the parameter of carbofuran COD reduction. The significance of the electrochemical peroxidation method and the conventional electrochemical method was compared as a preliminary test. The COD reduction of Carbofuran using traditional electrochemical methods and electrochemical peroxidation was 45.76% and 88.70%, respectively. Batch carbofuran electrochemical peroxidation process was accomplished to ascertain the optimum conditions under various operation times, the concentration of Na2SO4, and the additional volume of H2O2. The largest COD reduction of 93.78% was obtained at 10 minutes, 75 mM Na2SO4, and 2 mL H2O2. The UV-Vis spectrophotometric absorption of Carbofuran at a wavelength of 274 nm was significantly reduced from 1.377 to 0.131 at optimum conditions. The IR spectrum measurement results indicate a reduction in absorbance for the N-H group (3383 cm-1) and the C=O group (1643 cm-1) at optimum conditions. Overall, the electrochemical peroxidation process proved to be an appropriate technique for COD reduction of Carbofuran in Furadan 3GR pesticides.
Korelasi Konsentrasi Etanol 5% Pada Bahan Bakar Gasolin Terhadap Performa, dan Emisi Gas Buang Mesin Bensin 150cc Syarifudin Syarifudin; Eflita Yohana; Muchammad Muchammad; Suhartana Suhartana; Faqih Fatkhurrozak; Firman Lukman Sanjaya; M. Taufik Qurohman
Infotekmesin Vol 14 No 1 (2023): Infotekmesin: Januari, 2023
Publisher : P3M Politeknik Negeri Cilacap

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35970/infotekmesin.v14i1.1737

Abstract

Ethanol has higher octane and oxygen properties than fossil-fuel gasoline. Along with the increase in gasoline dependency and exhaust emissions, the use of ethanol as a fuel is urgently studied. This study aimed to observe the concentration of 5% ethanol in gasoline on the performance and exhaust emissions of a 150cc gasoline engine that was operated at 1000, 2000, and 3000rpm. The observation results show that the concentration of 5% ethanol in gasoline correlates with an increase in performance with indications of an increase in EGT, Brake power, BTE, and a decrease in SFC. On the emission side, it is also correlated with an increase in the quality of exhaust emissions with indications of increased CO2 emissions and reduced CO and HC emissions. The best correlation of 5% ethanol concentration was obtained at an operating speed of 2000rpm with an increase in EGT of 10.70%, an increase in Brake power of 9.49%, an increase in BTE of 38.62%, an increase in CO2 emissions of 23.06%, a decrease in SFC of 26 .49%, CO emission reduction of 16.67%, and HC emission reduction of 4.24%.
Optimization of Electrocoagulation Conditions in the Degradation Process of Carbofuran Waste (Furadan 3GR) Using Al/Graphite Electrodes Damar Nurwahyu Bima; Kumala Devi; Suhartana Suhartana; Sriyanti Sriyanti
ALCHEMY:Journal of Chemistry Vol 11, No 1 (2023): ALCHEMY: JOURNAL OF CHEMISTRY
Publisher : Department of Chemistry, Faculty of Science and Technology UIN Maulana Malik Ibrahim Malan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/al.v11i1.15360

Abstract

Electrocoagulation is one of the electrochemical methods for treating wastewater and separating pollutants. In this research, the electrocoagulation using Al/Graphite electrodes was applied to artistic wastewater containing carbofuran to see the reduction of its chemical oxygen demand(COD). The electrocoagulation process was chosen in this study based on several advantages, including easy to separate between impurities and the sample and a simple operating system. Several parameters such as electrolysis time, variations in electrolyte concentration, and the effect of pH have been investigated for their impact on the electrocoagulation process. The results showed that the proportion of the best reduction in chemical oxygen demand (COD) was 64.40%. The best conditions were an electrolysis time of 60 minutes, an electrolyte concentration of 0.15 M, and a pH of 10. The results also show that the decrease in chemical oxygen demand (COD) dependson those parameters. These results were investigated further by characterization using UV-Vis spectrophotometry and FTIR spectroscopy. The results of the UV-Vis spectrum showed a decrease in intensity at a wavelength of 275 nm. Analysis of the FTIR spectrum between the initial sample and the results of the electrocoagulation showed that there were similar absorption peaks but with much smaller intensity, indicating that the effluent's pollutants have been deposited.Keywords: Electrocoagulation, Carbofuran, Al/Graphite, COD
Activation of Natural Zeolite and Its Application for Adsorbents in Domestic Wastewater Treatment in Tembalang District, Semarang City Suhartana Suhartana; Pardoyo Pardoyo
Jurnal Kimia Sains dan Aplikasi Vol 23, No 1 (2020): Volume 23 Issue 1 Year 2020
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2575.252 KB) | DOI: 10.14710/jksa.23.1.28-33

Abstract

Tembalang is one of the districts in the city of Semarang whose economic growth is rapid. There are 12 sub-districts in Tembalang district, one of which is the Tembalang sub-district, which is within the campus area of Diponegoro University. When compared with other sub-district in the Tembalang district, the Tembalang sub-district community's need for clean water and domestic wastewater disposal is very high because of its dense population. Handling domestic wastewater is one of the environmental problems, which is interesting to study. Domestic wastewater, in addition to causing environmental pollution, can also cause discomfort and even health problems. One way to reduce the impact of domestic wastewater is to treat domestic wastewater before the environment is discharged. This study aims to describe the character of domestic wastewater in Tembalang sub-district, Tembalang district, Semarang city, and the use of activated zeolites and activated zeolites to reduce COD, pH, BOD, and TSS in domestic wastewater. Also, to compare the parameters of wastewater with regulations in force (Minister of Environment and Forestry Regulation No: 68 of 2016). This research is expected to improve the quality of domestic wastewater by adsorption using natural zeolite and activated zeolite adsorbents. The results showed that the adsorption treatment with natural zeolites and activated zeolites significantly improved water quality. The results of adsorption by natural zeolites showed a decrease in COD of 21.8%, a pH of 11.5%, BOD of 9.2%, and a TSS of 10.8%. Whereas adsorption by HCl-activated zeolite resulted in a decrease in COD of 78.9%, pH of 16.2%, BOD of 11.8% & TSS of 74.4%. While H2SO4-activated natural zeolite reduced COD by 85.5%, pH 17.9%, BOD 12.6% and TSS 89.7%.
Pengolahan Limbah Cair Industri Batik dengan Metoda Elektrokoagulasi Menggunakan Seng Bekas Sebagai Elektroda Noni Ika Rahmawati; Suhartana Suhartana; Gunawan Gunawan
Jurnal Kimia Sains dan Aplikasi Vol 12, No 2 (2009): Volume 12 Issue 2 Year 2009
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (737.468 KB) | DOI: 10.14710/jksa.12.2.40-46

Abstract

Telah dilakukan penelitian pengolahan limbah cair industri batik dengan metoda elektrokoagulasi menggunakan seng bekas sebagai elektroda yang bertujuan untuk memisahkan zat warna naftol dari limbah. Selama proses elektrokoagulasi logam seng mampu membentuk Zn(OH)2 yang berperan sebagai adsorben zat warna. Karena floks Zn(OH)2 mampu mengadsorpsi zat warna naftol sehingga zat warna dapat dipisahkan dari limbah. Pada proses elektrokoagulasi dilakukan penentuan kondisi terbaik yang meliputi potensial aplikasi, variasi pH dan waktu elektrolisis. Hasil penelitian menunjukkan bahwa diperoleh potensial aplikasi sebesar 7 volt dengan pH terbaik 12 dengan waktu elektrolisis selama 20 menit. Pada temperatur kamar, elektrokoagulasi limbah cair batik memberikan penurunan absorbansi sebesar 97,64 %, sedangkan penurunan kandungan COD, TSS dan kekeruhan masing-masing adalah 80,38 %, 96,38 % dan 97,61 %. Pada uji FTIR menunjukkan adanya kemiripan serapan yang muncul antara limbah sebelum elektrolisis dan endapan hasil elektrolisis. Hal ini menunjukkan bahwa sebagian besar zat warna telah dapat dipisahkan dari limbah cair dan metode elektrokoagulasi dapat diaplikasikan untuk mengatasi limbah cair berwarna.
Pemanfaatan Sekam Padi sebagai Bahan Baku Arang Aktif dan Aplikasinya untuk Penjernihan Air Sumur di Desa Asinan Kecamatan Bawen Kabupaten Semarang Suhartana Suhartana
Jurnal Kimia Sains dan Aplikasi Vol 10, No 3 (2007): Volume 10 Issue 3 Year 2007
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (352.923 KB) | DOI: 10.14710/jksa.10.3.67-71

Abstract

Di zaman orde baru Negara kita pernah menjadi Swasembada pangan, dengan dicanangkan program Desa Swasembada. Dengan program tersebut, produksi gabah melimpah ruah. Gabah tersusun dari kulit luar (sekam), kulit ari, endosperm dan lembaga. Dalam penelitian ini dilakukan pengarangan terhadap sekam padi, kemudian dibuat menjadi arang aktif. Produk arang aktif digunakan untuk menjernihkan air sumur dari desa Asinan kecamatan Bawen Kabupaten Semarang. Hasil yang diperoleh terjadi penurunan pH, angka kesadahan, kandungan NaCl, BOD, dan COD.
Zeolit Alam Termodifikasi Logam Fe sebagai Adsorben Fosfat (PO43-) pada Air Limbah Marwan Faisal; Suhartana Suhartana; Pardoyo Pardoyo
Jurnal Kimia Sains dan Aplikasi Vol 18, No 3 (2015): Volume 18 Issue 3 Year 2015
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (577.991 KB) | DOI: 10.14710/jksa.18.3.91-95

Abstract

Penelitian tentang zeolit alam termodifikasi logam Fe sebagai adsorben fosfat (PO43-) pada air limbah telah dilakukan. Zeolit alam diaktivasi menggunakan HCl 2M. Kemudian zeolit teraktivasi dimodifikasi menggunakan FeCl3.6H2O dengan perbandingan massa precursor 10:90, 25:75, 50:50, 75:25, 90:10. Metode modifikasi yang digunakan adalah impregnasi ion logam Fe3+. Pada zeolit-Fe yang diperoleh kemudian dilakukan untuk mengadsorpsi fosfat dengan konsentrasi awal 0,9883 ppm. Hasil yang diperoleh dianalisis dengan FTIR, dan Spektrofotometer UV-Vis. Hasil analisis FTIR terhadap zeolit-Fe menunjukkan adanya puncak pada bilangan gelombang 474,5 cm-1 yang mengindikasikan vibrasi Fe-O. Fosfat (PO43-) yang terserap oleh zeolit-Fe paling banyak diperoleh pada variasi 10:90 yaitu sebesar 30,54% dengan konsentrasi teradsorpsi sebesar 0,3019 mgL-1.
Dealuminasi Zeolit Alam Menggunakan Asam (HCl dan H2SO4) untuk Katalis pada Proses Sintesis Biodiesel Sugiarti Norvia; Suhartana Suhartana; Pardoyo Pardoyo
Jurnal Kimia Sains dan Aplikasi Vol 19, No 2 (2016): Volume 19 Issue 2 Year 2016
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (381.079 KB) | DOI: 10.14710/jksa.19.2.72-76

Abstract

Telah dilakukan dealuminasi zeolit alam menggunakan asam (HCl dan H2SO4) untuk katalis pada proses sintesis biodiesel. Zeolit dianalisis dengan AAS dan FTIR serta uji aktivitas katalis pada sintesis biodiesel dengan metode GC-MS. Didapatkan bahwa H2SO4 lebih efektif mendealuminasi zeolite dibandingkan dengan HCl. Hasil spektrogram FTIR menunjukkan bahwa proses dealuminasi asam mengakibatkan perubahan bilangan gelombang dan rasio Si/Al yang cukup signifikan, di mana pada rasio Si/Al zeolit meningkat dari 4,57 menjadi 5,41 pada zeolit alam dealuminasi HCl dan menjadi 6,42 pada zeolit alam dealuminasi H2SO4. Zeolit terdealuminasi mampu bekerja sebagai katalis dalam sintesis biodiesel di mana katalis zeolit dealuminasi H2SO4 menghasilkan metil ester dengan senyawa dominan asam 9-oktadekenoat dengan persentase luas area sebesar 63,21% lebih banyak dibandingkan pada katalis zeolit dealuminasi HCl dan zeolite belum didealuminasi.