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Abstrak :
Anoda korban paduan Aluminium yang umum digunakan berpotensi memicu terjadinya Stress Corrosion Cracking dan Hydrogen Embrittlement pada struktur yang diproteksi. Anoda korban potensial rendah Low Voltage Sacrificial Anode dengan potensial dibawah -800 mV vs Ag/AgCl dikembangkan untuk mengatasi permasalahan tersebut. Karakteristik paduan Al-5Zn-0,5Cu dengan variasi penambahan Samarium 0,02 wt , 0,1 wt , 0,3 wt , dan 0,5 wt diteliti pada penelitian ini. Paduan Al-5Zn-0,02In yang umum digunakan juga turut diuji sebagai pembanding. Pengujian efisiensi anoda dengan metode kehilangan berat sesuai standar DNVGL-RP-B401 dan pengujian Electrochemical Impedance Spectroscopy EIS dilakukan untuk mengetahui performa dan karakteristik korosi anoda korban paduan Al-5Zn-0,5Cu-xSm. Penambahan unsur Samarium dengan kadar 0,1 wt menunjukan performa anoda korban yang paling baik dengan kapasitas elektrokimia 2809,80 Ah/kg dan efisiensi 98. ......Commonly used Aluminum alloy sacrificial anodes have the potential to trigger the occurrence of Stress Corrosion Cracking and Hydrogen Embrittlement on a protected structure. Low Voltage Sacrificial Anode with potential under 800 mV vs. Ag AgCl was developed to overcome this problem. Electrochemical behaviour of Al 5Zn 0,5Cu alloy with variations of Samarium addition of 0.02 wt , 0.1 wt , 0.3 wt , and 0.5 wt were investigated in this study. The commonly used Al 5Zn 0.02In alloy is also tested as a comparison. Anode efficiency test with weight loss method according to DNVGL RP B401 standard and Electrochemical Impedance Spectroscopy EIS testing was performed to determine the performance and corrosion characteristics of Al 5Zn 0,5Cu xSm alloy. The addition of Samarium element with 0.1 wt content shows the best anode performance with electrochemical capacity 2809,80 Ah kg and 98 efficiency.

Abstrak :
Corrosion is one of some necessary field that must be concorned by maritime and ship industries in Indonesia. The phenomenon of corrosion should be more attended, because it makes much money lost unpredictly. Corrosion couldn,t be avoid because the process happens natyrally but corrosion must be controlled to minimize the negative effects, specially in economics technics and safety fields. One of some popular methods to control the corrosion process in cathodic protection methods, with sacrificial anode. This research observed the effectivity of znanode (type S-3) that is used to protect a kind of material as cathode. The cathode material is A grade of mild steels, a material that is commonly used for many sea water constructions espicially for ship building materials. The observation was taken in fluid laboratory, marine engineering departement, the faculty of marine engineering & science, Hang Tuah University Surabaya. The weigh of sacrificial anode and the cathode is 1:4. They are connected and immersed in a model vessel with 35%o salinity sea water as corrosion media. This research presents that the average weight lost of the sacrificial anode is 1.637% and the average weigh lost of the cathode is 0.170% in 16 weeks observation. The calculation predicted that the sacrificial anode will be lost 5.5% of the weight in a year.

Abstrak :
Pengendalian korosi pada lambung kapal baja di bawah air laut umumnya dilakukan dengan cara pelapisan cat dan pemasangan zinc-anode. Dalam hal ini telah dilakukan studi tentang efektifitas pengendalian korosi dengan pelapisan cat dan pemasangan zinc-anode. Pelat baja lambung kapal yang diteliti, sesuai sertifikasi klasifikasi perkapalan yang dilindungi dengan pelapisan cat dan pemasangan zinc-anode, direndam dalam air laut secara alami selama kurang lebih enam bulan. Untuk mengetahui efektifitas pengendalian korosi dilakukan pengamatan dan pengujian material-material yang dipergunakan dengan pengukuran difraksi sinar-X, tes adhesi, tes hardness dan perhitungan laju korosinya. Setelah dilakukan penelitian diperoleh cara yang cocok dan umur dari metode pengendalian korosi yang sesuai dengan kondisi di lingkungan perairan di Indonesia, yaitu pengendalian korosi yang dikombinasi dengan pengecatan dan pemasangan anoda karbon yang lebih efektif. ...... Corrosion control in a steel plate hull of a ship is generally done by applying paint coating and zinc anode of the hull. A study on corrosion control effectiveness by applying paint coating and zinc anode has been done. Observed certified steel plates ship's hull, coated with certain type of paint protection and zinc anode, are submerged in sea water on a period of six month. To obtain effectiveness of the method applied, the materials are observed and tested by using X-ray diffraction, adhesion test, hardness test, and corrosion rate calculation. It is obtained that a specific method of controlling corrosion in a specific area such as in Indonesian tropic waters should be done effectively by combining the coating and anodic protection.

Abstrak :
Pembuatan komposit Li4Ti5O12-Sn nano/Grafin telah berhasil dilakukan sebagai material anoda pada baterai ion litium. Penambahan material grafin komersial dengan variasi berat 1%, 3% dan 5% dan waktu sonikasi selama 45 menit dan 75 menit telah dilaksanakan. Sintesis dari  Li4Ti5O12 dilakukan dengan membuat prekursor TiO2 menggunakan metode sol-gel dan sudah dikalsinasi yang dicampurkan dengan LiOH dengan metode solid-state reaction dan proses sintering. Material Li4Ti5O12 dicampurkan dengan serbuk Sn nano dengan berat 10% untuk mendapatkan material komposit Li4Ti5O12-Sn nano. Pembuatan komposit Li4Ti5O12-Sn nano/Grafin dimulai dari penambahan variasi berat grafin komersial yang berbeda dengan metode wet milling menggunakan planetary ball mill selama 1 jam dan dilanjutkan dengan proses sonikasi menggunakan ultrasonic homogenizer dengan variasi waktu berbeda sebelum akhirnya dilakukan kalsinasi menggunakan vacuum furnace dengan gas N2 pada temperatur 500°C selama 5 jam. Hasil penelitian menunjukan bahwa adanya peningkatan performa dilihat dari kapasitas spesifik dari komposit Li4Ti5O12-Sn nano dengan penambahan berat grafin yang optimum pada 5% dengan waktu sonikasi 75 menit walaupun terdapat beberapa pengotor yang terdeteksi pada hasil pengujian XRD. Secara umum performa baterai sangat baik pada siklus yang tinggi dengan pengurangan discharge capacity yang minor dan dengan penambahan grafin dapat meningkatkan kapasitas spesifik dari material komposit Li4Ti5O12-Sn nano. ......The synthesis of Li4Ti5O12-Sn nano/Graphene composite has been successfully carried out as an anode material for lithium-ion battery. The addition of commercial graphene with a weight variation of 1%, 3% and 5% and sonication time of 45 minutes and 75 minutes has been done successfully. Synthesis of Li4Ti5O12 is done by making TiO2 precursors using sol-gel method and has been calcined, followed by solid-state reaction with LiOH sintering process. The Li4Ti5O12 material is mixed with Sn nano powder with a weight of 10% to obtain L4Ti5O12-Sn nano composite material. Production of Li4Ti5O12-Sn nano/Graphene composites start from mixing different commercial graphene weight variations by wet milling method using planetary ball mill for 1 hour and continued with sonication process using ultrasonic homogenizer with different time variations before calcination process using a vacuum furnace with N2 gas at 500°C for 5 hours. Li4Ti5O12-Sn nano with an optimal maximum weight at 5% with a sonication time of 75 minutes including some impurities reported on the XRD results. In general, the battery samples are very good at high cycles with overall small capacity fade.

Abstrak :
Pada proses pengolahan decopperized anode slime sebagai by product dari proses pemurnian tembaga dengan metode hydrometallurgy yaitu dengan proses leaching menggunakan oksidator sodium hipoklorit diperoleh dua jenis produk utama berupa filtrat yang kaya akan emas dan residu klorida yang memiliki kandungan perak. Pada filtrat dan residu ini dilakukan proses lanjutan yang berbeda untuk memperoleh logam-logam berharga yang memiliki nilai ekonomis. Penelitian ini merupakan salah usaha untuk merecovery perak dari decopperized anode slime eks PT Smelting Gresik dengan metode selektif leaching dengan menggunakan ammonium hidroksida.. Pada percobaan ini divariasiakan konsentrasi ammonium hidroksida dan waktu tinggal untuk menentukan titik optimum proses pelindian terhadap recovery perak, Sedangkan temperature proses dan kecepatan putaran dibuat tetap pada 120 RPM dan temperatur proses pada 60°C. Hasil dari penelitian ini diperoleh data bahwa untuk merecovery perak dengan metode selective leaching diperoleh titik optimum persen ekstraksi perak pada kondisi konsentrasi ammonium hidroksida sebesar 30 ml (0,375M) dan waktu proses untuk memperoleh persen ekstraksi pada waktu tinggl selama 60 menit, yaitu diperoleh persen ekstraksi sebesar 85,21%. Dari reduksi AgCl dengan menggunakan Zn Powder diperoleh perak dengan kadar kemurnian sebesar 98,11%. ......In the processing of decopperized anode slime as by-product of copper refining process by the method of hydrometallurgy, the process of leaching using oxidant of sodium hypochlorite obtained two kinds of main products in the form of filtrate that is rich in gold and residues that contain silver chloride. In the filtrate and the residue was carried out follow-up of different processes to obtain precious metals that have economic value. This study is one attempt to recover silver from PT Smelting Gresik decopperized anode slime by selective leaching method using ammonium hydroxide. In this experiment varied the concentration of ammonium hydroxide and residence time to determine the optimum leaching process to recover the silver, while the process temperature and rotation speed is made permanent at 120 RPM and at 60°C of process temperature. The results of this study data showed that to recover the silver by selective leaching method obtained the optimum percent extraction of silver on the condition of the concentration of ammonium hydroxide at 30 ml (0.375 M) and the processing time to obtain the percent extraction at 60 minutes, the obtained percent extraction is 85.21%. From the reduction of AgCl using Zn Powder obtained metallic silver with purity 98.11% of silver.

Abstrak :
ABSTRACT
Sodium-ion batteries (SIBs) is a strong contender for as a new battery system over lithium-ion batteries (LIBs) for rechargeable large-scale energy storage applications. Cathode materials for SIBs have been well developed. Anode materials, on the other hand, are still under development. Transition metal oxides cumulating Na ions by chemically conversion reactions and intercalation mechanism have made extensive research interest due to its high theoretical capacity. In particular, tin dioxide has been primarily studied as an auspicious anode material for both LIBs and SIBs. However, significant volume changes take place during battery charging and discharging, especially in SIBs. It has been well documented that the electrochemical properties of the material can be enhanced by using several strategies, such as nanostructuring and doping of a second element, such as cobalt (Co). In this study, porous CoSnO3 nanocubes were synthesised, characterised, and tested against SIBs. The material yielded a performance of 306.7 mAhg-1 sodium-ion storage capacity at a current density of 50 mAg-1, which is quite a high number when compared with other anode material such as nickel oxide (300 mAhg-1), tin dioxide (170 mAhg-1), and cobalt oxide (153.8 mAhg-1).

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ABSTRAK
Baterai sodium-ion atau Sodium-Ion Batteries (SIBs) adalah pesaing kuat untuk sebagai sistem baterai baru dibandingkan baterai lithium-ion atau Lithium-Ion Batteries (LIBs) untuk aplikasi penyimpanan energi skala besar yang dapat diisi ulang. Bahan katoda untuk SIB telah dikembangkan dengan baik. Bahan anoda, di sisi lain, masih dalam pengembangan. Oksida logam transisi yang mengakumulasi ion-ion Na dengan reaksi konversi kimia dan mekanisme interkalasi telah menghasilkan minat penelitian yang luas karena kapasitas teoretisnya yang tinggi. Secara khusus, timah dioksida telah dipelajari terutama sebagai bahan anoda yang menguntungkan baik untuk LIB maupun SIB. Namun, perubahan volume yang signifikan terjadi selama pengisian dan pemakaian baterai, terutama pada SIB. Telah didokumentasikan dengan baik bahwa sifat elektrokimia material dapat ditingkatkan dengan menggunakan beberapa strategi, seperti nanostrukturisasi dan doping elemen kedua, seperti kobalt (Co). Dalam penelitian ini, nanocube CoSnO3 berpori disintesis, dikarakterisasi, dan diuji terhadap SIB. Bahan ini menghasilkan kinerja 306,7 mAhg-1 kapasitas penyimpanan sodium-ion pada kepadatan arus 50 mAg-1, yang jumlahnya cukup tinggi jika dibandingkan dengan bahan anoda lainnya seperti oksida nikel (300 mAhg-1), timah dioksida (170 mAhg-1), dan kobal oksida (153,8 mAhg-1).

Abstrak :
The purpose of this research was to find other material to be alloyed to aluminum which is cheap, not a dangerous compound, which can be carted as simple as possible and should be as far as possible found in Indonesia. Tin, zinc, and indium, are metals to be alloyed which were reported gave a better performance to aluminum sacrificial anode, although the latest mentioned is difficult to be found in Indonesia. The alloying was done by simple casting. The investigation started with alloying aluminum with 5% Zn , and tin added in varying weights from of 0.004, 0.006, 0.008, 0.01, 0.04, 0.1, to 0.2 percent. The second was also 5% Zn and Indium in varying weights as from 0.004, 0.005, 0.02, 0.05, 0.07, to 0.08 percent. Anode potential, cathodic protection potential, the capacity of anode, anode output, anode efficiency, the anode corrosion patron and induction time were points being investigated to know the anode performance, gained by immersed test in 3% sodium chloride solution. The efficiency of 77 % can be obtained from 5% Zn and 0,1 % Sn aluminum alloy and for comparison, 5% Zn and 0.05% indium aluminum alloy can reach an efficiency of 86 %. The Sn, Zn aluminum alloys, have an anode potential of -1.15 volt, cathodic protection potential -1,06 volt , capacity of 2558 A.h/kg, while the Indium, Zn aluminum alloy has -1.155 volt anode potential, capacity of 2543 Ah/kg , and anode out put of 4.76 ampere. During the immersion time Al-Zn-Sn alloys give more stable cathodic protection potential.

Abstrak :
Penelitian kali ini adalah berfokus terhadap pengaruh unsur logam tanah jarang Samarium Sm terhadap morofologi pada struktur mikro saat proses solidifkasi. Penambahan unsur Samarium sebesar 0.1; 0.3; 0.5 wt pada matriks Al-5Zn-0.5Si yang nantinya akan dilihat terhadap sifat dari mekanisme korosi yang terjadi dan efisiensi dari anoda korban Al-5Zn-0.5Si. Alumunium paduan pada penelitian ini akan mencapai sifat optimum jika dilihat dari struktur mikro pada konsentrasi 0.5 , tetapi bertolak belakang terhadap mekanisme korosi yang terjadi pada anoda korban. Dimana dengan semakin di tambahkannya unsur Samarium, morfologi dari butir akan semakin halus dan equixed, tetapi laju korosi pada anoda korban akan semakin menurun. Pengaruh DSC Differential Scanning Calorimetry pada mikrostruktur terlihat dari bentuk presipitat yang hadir pada batas butir. Dengan penambahan unsur Samarium pada anoda korban Al-5Zn-0.5Si menghasilkan fasa yang terbentuk antara lain AlSiSm,Al2Si2Sm yang dapat mempengaruhi efisiensi dari anoda korban.

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The research is focused on the effect of rare earth Samarium Sm element on the microstructure morphology during the solidification proccess. The concentration of Samarium Sm addition are 0.1 0.3 0.5 wt on Al 5Zn 0.5Si matrix and corelated to the characteristic and mechanism of corrosion proccess in Al 5Zn 0.5Si sacrificial anode. In this research, Aluminium alloy will get the optimum addition if it seen from the microstructure at 0.5 wt addition, but it reverse to the corrosion mechanism on the sacrificial anode. The more and more addition of Samarium, the morphology of microstructure is finer and equixed, but the corrosion rate of the sacrificial anode decrease. The effect of Differential Scanning Calorimetry DSC on the microstructure can be seen on the morphology of the presipitate. With the addition of the element Samarium on the sacrificial anode Al 5Zn 0.5Si produce phase formed are AlSiSm, Al2Si2Sm which may affect the efficiency of the sacrificial anode.

Abstrak :
Penelitian ini yang berfokus pada pengaruh unsur logam tanah jarang cerium Ce terhadap fasa intermetalik yang terbentuk pada saat proses solidifikasi, dimana unsur cerium Ce ditambahkan sebesar 0.1; 0.3; dan 0.5 wt pada matriks paduan Al-5Zn-0.5Si. Penambahan unsur cerium Ce yang semakin banyak ,sesuai dengan urutannya, maka anoda korban akan semakin baik efisiensinya. Cerium Ce yang ditambahkan pada proses tersebut akan berpengaruh terhadap ketahanan Icorr yaitu 0.8x10-5, 1.3x10-5, 2.9x10-5 Volt, sebagai efisiensi anoda korban. Selain itu, penambahan cerium Ce yang semakin banyak akan membuat ukuran butir menjadi lebih kecil, yaitu 108.42, 97.14, 94.55 mm. Fasa intermetalik yang terbentuk dapat dilihat pada grafik yang dihasilkan dari pengujian DSC Differential Scanning Calorimetry , dimana grafik tersebut menjelaskan adanya fasa AlCeSi2 Al Si dan Al2Zn2Ce yang dapat mempengaruhi efiensi anoda korban.

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The research is focusing on the influence of rare earth cerium Ce element on intermetallic phase that is formed on the solidification process, where cerium Ce is added on 0.1 0.3 and 0.5 wt level on Al 5Zn 0.5Si alloy as microstructure rsquo s grain refiner and precipitates rsquo refiner which will be formed on the solidification process. The more cerium Ce added gradually, the better sacrificial anode efficiency to be exposed to corrosion. The addition of more cerium Ce will make the grain size smaller from 108.42, 97.14, 94.55 mm. The added cerium Ce will be affected on the Icorr from 0.8x10 5, 1.3x10 5, 2.9x10 5 Volt, as sacrificial anode efficiency. The intermetallic phase formed can be seen in the graph generated from the DSC Differential Scanning Calorimetry testing, which describes the presence of AlCeSi2 Al Si and Al2Zn2Ce phases that may affect the effectiveness of sacrificial anodes.

Abstrak :
Dilakukan survey resistivitas tanah per 1 (satu) kilometer sepanjang pipeline dengan menggunakan metode four pin mengggunakan alat soil box untuk mendapatkan data perancangan proteksi katodik. Dari perhitungan dengan metode masa dan metode arus listrik yang dikeluarkan diperoleh jumlah anoda magnesium dengan spesifikasi berat 14,5 Kg, penampang melintang 0.015 m² dan panjang 0.55 m pada setiap satu kilometer pipa dengan spacing 0.914 m. Berdasarkan referensi data pipa, lingkungan, spesifikasi anoda korban, spesifikasi material urug dan resistivitas tanah, perancangan jumlah anoda korban yang dipasang pada pipa dihitung. Pengecekan perlindungan proteksi katodik dilakukan dengan pengetesan potensial polarisasi dan perhitungan hambatan total dilapangan sehingga arus korosi dan laju korosinya dapat diperkirakan. Perbandingan dilakukan dengan menguji laju korosi material API 5L Grade B di laboratorium dengan alat potensiostat yang menggunakan metode polarisasi sehingga kriteria perlindungan berdasarkan standard NACE RP 0169 dapat diklarifikasi. Penelitian juga dikembangkan dengan melihat perilaku korosi material pipa dengan pengujian struktur mikro, mekanik dan komposisi kimia pada pipa baru dan yang pipa telah terkorosi (akibat alat uji potensiostat). Juga sebagai pembanding, sampel pipa gagal akibat korosi turut diuji struktur mikro dan komposisi kimianya. Data dari pengujian ini akan memberikan gambaran mengenai disain umur pipa yang dirancang untuk kondisi dengan tekanan dan temperatur tertentu. ......A survey of soil resistivity per 1 (one) kilometer along the pipeline using the four pin method of a soil box tool to obtain cathodic protection design data. From the calculation with the mass method and the electric current method that was released, the number of magnesium anodes with a weight specification of 14.5 Kg, a cross section of 0.015 m2 and a length of 0.55 m in per one kilometer pipeline with spacing of 0.914 m. Based on pipe data references, environment, sacrificial anode specifications, load material specifications and soil resistivity, the design of quantity scarifical anodes installed on the pipe is calculated. Checking cathodic protection protection is done by testing the potential of polarization and calculating the total resistance in the field so that the corrosion current and the corrosion rate can be estimated. Comparison was carried out by testing the corrosion rate of API 5L Grade B material in the laboratory with a potentiostat device using the polarization method so that the protection criteria based on the NACE standard of Rp. 0169 could be verified. Research was also developed by looking at the corrosion behavior of pipe material by testing the microstructure, mechanics and chemical composition of the new pipe and the pipe has been corroded (due to the potentiostat test equipment). Also as a comparison, the defect pipe samples due to corrosion were tested for microstructure and chemical composition. Data from this test will provide an overview of the design life of pipes designed for conditions with certain pressure and temperature.