Corrosion Studies on Ss-321 in Natrium-Hydroxide Solution

Corrosion Studies On Ss-321 In Natrium-Hydroxide Solution. Experimental corrosionstudies on commercial SS-321 have been carried out. The experiments were carried out in a sodiumhydroxide medium with a concentration variation of 0.4 M. 0.5 M, 0.6 M, and0.7Mcorresponding topHvalues of 13.6, 13.69, 13.78, and 13.84 respectively. The experiments were carried out using a type ofM-273 EG&Gpotentiostat/galvanometer test instrument. The post-corrosion samples' microstructure wereanalyzed with the aid of EDS (energy dispersive spectroscopy) equipped SEM instrument to detect thepresence of any viable corrosion byproducts. Forfurther verification x-ray diffraction method was alsoused to detect any possible emerging corrosion byproducts on the samples' surfaces correlated to theSEM-EDS result. Experimental results confirm that A1SI-321 commercial alloys immersed in a natriumhydroxide corrosion medium with a variation of concentration experience very little or almost nocorrosion, so that according to the so-called Fontana's criteria these test-materials turn out to have anexcellent resistance toward natrium hydroxide corrosion. This is also evidenced by the very low corrosionrate value measured in this study. EDS study and X-ray diffraction results indicate that the possibleensuing corrosion byproducts are iron oxides, chromeoxides and silicon oxides

Karakterisasi Korosi Baja SS-430 pada lingkungan NaCL

SS-430 is a ferrite type alloy that can be selected for the base material of sea-water duct-pipes in the water supply system of a power reactor, but in general the ferritic alloy is not as good as austenitic with respect to corrosion resistance. Then NaCl environment is used to examine corrosion rate of SS-430. The corrosion was observed in four concentrations of NaCl solution. The experiments were carried out using M-273 EG&G potentiostate test instrument with polarization methode. The microstructure of post-corrosion samples were analyzed with an EDS attached to SEM instrument to detect the presence of any viable corrosion byproducts. X-ray diffraction methode was also used to detect any possible emerging corrosion on samples surfaces. The results showed that SS-430 suffers very little corrosion in NaCl environment, and that this material turn out to have an outstanding resistance toward NaCl corrosion. The possible ensuing corrosion byproducts are chrome oxides and iron oxides

Li Ion Conducting Polymer Based On Polyvinylidene Fluoride And Li Triflate

Li ION CONDUCTING POLYMER BASED ON POLYVINYLIDENE FLUORIDE AND Li TRIFLATE. A Series of polymer electrolyte based on Polyvinylidene Fluoride (PVDF) for solid state rechargeable lithium battery has been prepared by solution casting technique. Lithium triflate salt was used as filler with various compositions. Bulk nature and surface morphology of the polymer electrolytes were studied by X-Ray Diffractometer (XRD) and Scanning Electron Microscope (SEM), respectively. The thermal properties of polymer and salt were confirmed by Differential Scanning Calorimeter (DSC). The electrical properties of electrolyte polymer membrane were studied by using impedance spectrometer. It was found that the highest ionic conductivity was obtained for PVDF + Li Triflate 10%(w/w) which is 4.5411 x 10-3 S/cm. It was also found that there was peak of each composition in the loss tangent suggests the presence of relaxing dipoles in the polymer electrolyte films. The peak shifts towards higher frequency side suggesting the speed up of the relaxation time

Pembuatan Bahan Polimer Elektrolit Padat Berbasis Nanokomposit Kitosan Montmorillonite Untuk Aplikasi Baterai

Telah dilakukan pembuatan bahan polimer elektrolit padat berbasis nanokomposit kitosan montmorillonite yang diaplikasikan dalam sistem baterai. Penelitian ini dilakukan dengan tujuan untuk menentukan komposisi optimal antara kitosan, montmorillonite dan LiClO4 sehingga diperoleh membran dengan karakteristik yang paling baik. Teknik pembuatan membran dilakukan menggunakan metode casting. Terdapat dua seri sampel yang akan di uji, yaitu membran dengan variasi komposisi montmorillonite dan variasi komposisi LiClO4. Komposisi kitosan dan montmorillonite yang digunakan pada sampel seri kedua diperoleh dari komposisi optimal membran kitosan-montmorillonite pada sampel seri pertama. Karakterisasi yang dilakukan meliputi uji tarik, pengukuran konduktivitas ionik dan identifikasi menggunakan difraksi sinar X. Penambahan montmorillonite meningkatkan kuat tarik membran dan konduktivitas ionik setelah ditambah LiClO4. Pada kondisi optimal diperoleh konduktivitas ionik 2,383 x 10-5 S/cm dan kuat tarik 15,19 Mpa pada komposisi montmorillonit 5% b/b dan LiClO4 40%. Hasil analisis difraksi sinar X menunjukkan terjadi proses interkalasi polimer kitosan ke dalam montmorillonite

SINTESIS DAN KAJIAN PERILAKU KONDUKTIVITAS KOMPOSISI BARU ELEKTROLIT PADAT (Li2O)x(P2O5)y

Bahan elektrolit padat (Li2O)x(P2O5)y dengan komposisi konten Li2O sebesar x = 24 %berat dan 28 %berat telah dipreparasi menggunakan teknik reaksi padat pada suhu di bawah suhu lelehnya.  Paduan yang telah dipreparasi kemudian dikarakterisasi menggunakan Scanning Electron Microscopy (SEM) dan Electrochemical Impedance Spectroscopy (EIS) untuk diperiksa morfologi, sifat elektrokimia dan konduktivitasnya. Karakterisasi elektrokimia menunjukkan bahwa nilai konduktivitas kedua paduan berada pada orde 10-6S/cm, setara dengan nilai konduktivitas paduan Li4P2O7 yang dipreparasi pada suhu lebih tinggi dengan kandungan Li2O lebih banyak, dan lebih tinggi dari konduktivitas senyawa Li3PO4. Taksiran nilai eksponen frekuensi dari formula konduktivitas AC, memperlihatkan bahwa kemungkinan sumber konduksi ion dalam bahan yang diamati salah satunya adalah aliran ion jarak jauh. Kurva rugi dielektrik menunjukkan bahwa konduksi dalam bahan elektrolit ini didominasi oleh konduksi DC

Li ION CONDUCTING POLYMER BASED ON POLYVINYLIDENE FLUORIDE AND Li TRIFLATE

Li ION CONDUCTING POLYMER BASED ON POLYVINYLIDENE FLUORIDE AND Li TRIFLATE. A Series of polymer electrolyte based on Polyvinylidene Fluoride (PVDF) for solid state rechargeable lithium battery has been prepared by solution casting technique. Lithium triflate salt was used as filler with various compositions. Bulk nature and surface morphology of the polymer electrolytes were studied by X-Ray Diffractometer (XRD) and Scanning Electron Microscope (SEM), respectively. The thermal properties of polymer and salt were confirmed by Differential Scanning Calorimeter (DSC). The electrical properties of electrolyte polymer membrane were studied by using impedance spectrometer. It was found that the highest ionic conductivity was obtained for PVDF + Li Triflate 10%(w/w) which is 4.5411 x 10-3 S/cm. It was also found that there was peak of each composition in the loss tangent suggests the presence of relaxing dipoles in the polymer electrolyte films. The peak shifts towards higher frequency side suggesting the speed up of the relaxation time

Pembuatan Bahan Polimer Elektrolit Padat Berbasis Nanokomposit Kitosan Montmorillonite Untuk Aplikasi Baterai

Telah dilakukan pembuatan bahan polimer elektrolit padat berbasis nanokomposit kitosan montmorillonite yang diaplikasikan dalam sistem baterai. Penelitian ini dilakukan dengan tujuan untuk menentukan komposisi optimal antara kitosan, montmorillonite dan LiClO4 sehingga diperoleh membran dengan karakteristik yang paling baik. Teknik pembuatan membran dilakukan menggunakan metode casting. Terdapat dua seri sampel yang akan di uji, yaitu membran dengan variasi komposisi montmorillonite dan variasi komposisi LiClO4. Komposisi kitosan dan montmorillonite yang digunakan pada sampel seri kedua diperoleh dari komposisi optimal membran kitosan-montmorillonite pada sampel seri pertama. Karakterisasi yang dilakukan meliputi uji tarik, pengukuran konduktivitas ionik dan identifikasi menggunakan difraksi sinar X. Penambahan montmorillonite meningkatkan kuat tarik membran dan konduktivitas ionik setelah ditambah LiClO4. Pada kondisi optimal diperoleh konduktivitas ionik 2,383 x 10-5 S/cm dan kuat tarik 15,19 Mpa pada komposisi montmorillonit 5% b/b dan LiClO4 40%. Hasil analisis difraksi sinar X menunjukkan terjadi proses interkalasi polimer kitosan ke dalam montmorillonite.

Pembuatan Komposit Partikulat Onix Diperkuat Poliester Untuk Bahan Interior

Telah dilakukan penelitian pe,manfaatan limbah mineral batuan onix, untuk dijadikan onixartifisial dalam produk interior dengan memanfaatkan resin poliester sebagai pengikatnya. Bahan komposit partikulat onix bermatriks polimer dapat diharapkan sebagai bahan interior yang kedap air dan cukup ule

Synthesis of Lithium Titanate (Li4Ti5O12) by Addition of Excess Lithium Carbonate (Li2CO3) in Titanium Dioxide (TiO2) Xerogel

Lithium titanate, Li4Ti5O12 (LTO) is a promising candidate as lithium ion battery anode material. In this investigation, LTO was synthesized by a solid state method using TiO2 xerogel prepared by the sol-gel method and lithium carbonate (Li2CO3). Three variations of Li2CO3 content addition in mol% or Li2CO3 molar excess were fabricated, i.e., 0, 50 and 100%, labelled as sample LTO-1, LTO-2 and LTO-3, respectively. The characterizations were made using XRD, FESEM, and BET testing. These were performed to observe the effect of lithium excess addition on structure, morphology, and surface area of the resulting samples. Results showed that the crystallite size and surface area of each sample was 50.80 nm, 17.86 m2/gr for LTO-1; 53.14 nm, 22.53 m2/gr for LTO-2; and 38.09 nm, 16.80 m2/gr for LTO-3. Furthermore, lithium excess caused the formation of impure compound Li2TiO3, while a very small amount of rutile TiO2 was found in LTO-1. A near-pure crystalline Li4Ti5O12 compound was successfully synthesized using the present method with stoichiometric composition with 0% excess, indicating very little Li+ loss during the sintering process