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Sintesis kalsium pirofospat (Ca2P2O7) dari limbah cangkang telur dengan metode solvothermal Ihsanul Huda; Retno Kusumaningrum; Mi'raj Shabrin Jamil; Wahyu Bambang Widayatno; Agus Sukarto Wismogroho; Nurul Taufiqu Rochman; Alfian Noviyanto
CHEMPUBLISH JOURNAL Vol. 5 No. 1 (2020): Chempublish Journal
Publisher : Universitas Jambi, Fakultas Sains dan Teknologi, Program Studi Kimia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22437/chp.v5i1.8669

Abstract

Kalsium pirofospat telah berhasil disintesis dengan menggunakan metode solvothermal. Bahan dasar yang digunakan adalah limbah cangkang telur ayam dan bebek. Cangkang telur ayam dan bebek dibersihkan dan digerus, kemudian dikalsinasi pada temperatur 1000°C selama 2 jam untuk mendapatkan serbuk CaO. Serbuk CaO kemudian dicampurkan dengan H3PO4 dan dimasukkan ke dalam bejana solvothermal. Proses solvothermal dilakukan pada temperatur 130°C selama 16 jam. Fasa tunggal CaHPO4 diperoleh setelah proses solvothermal. Kalsinasi serbuk CaHPO4 dilakukan pada tungku muffle dengan temperatur 800°C selama 2 jam dan kondisi atmosfir biasa. Hasil analisa fasa menunjukkan terbentuknya fasa tunggal kalsium pirofospat (Ca2P2O7) tanpa adanya fasa pengotor lainnya. Hasil ini menunjukkan perbandingan Ca dan P adalah 1. Mikrostruktur kalsium pirofospat yang terbentuk agak kasar dengan ukuran partikel rata-rata 590 ± 43 nm untuk cangkang telur ayam dan 455 ± 32 nm untuk cangkang telur bebek. Studi lebih lanjut diperlukan untuk mendapatkan kondisi optimum dari proses solvothermal limbah cangkang telur sehingga bisa didapatkan kalsium pirofospat yang mempunyai ukuran lebih halus dan seragam.
THE EFFECT OF ADDITION GREEN INHIBITOR D-GALACTOSE ON CORROSION RATE OF ALUMINUM ALLOY 5052 IN SULFURIC ACID (H2SO4) MEDIA Muhajirin Muhajirin; I. G. A. Arwati; S. Hartati; H. Hakim; Alfian Noviyanto; Arramel Arramel; T. Zakly
International Journal of Innovation in Mechanical Engineering and Advanced Materials Vol 4, No 2 (2022)
Publisher : Universitas Mercu Buana, Prodi S2 Teknik Mesin

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/ijimeam.v4i2.16610

Abstract

Aluminum alloy 5052 (Al5052) is one of the metals used as a bipolar plate in a Proton Exchange Membrane Fuel Cell (PEMFC) due to has its light mass and being easy to form, and, has high conductivity and resistivity properties. This material is prone to corrosion and current knowledge to protect its surface is currently lacking. The product of PEMFC produces electrical energy, hot steam (313 – 353 K), and water. These conditions have an impact on the degraded bipolar plate caused by the acidic nafion membrane. This increases the risk of corrosion on the cathode side of the bipolar plate. Coating with a green inhibitor using the electrophoretic deposition technique (EPD) is one way to deal with the corrosion that occurs. The analysis method used electrochemical with potentiodynamic polarization techniques, electrochemistry impedance spectroscopy (EIS), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). In this study, green inhibitor D-galactose was used with a concentration of 0.5 – 1.5 g and an, EPD time of 15 – 45 minutes in 0.5 M sulfuric acid (H2SO4) media pH 1-4. Potentiodynamic polarization analysis at the lowest corrosion current value (Icorr) at demonstrates (the inhibitor concentration of 1.5 g with an and EPD time of 45 minutes) resulted corrosion rate of Al5052 before EPD was 0.0075 mmPY while the corrosion rate of Al5052 after EPD was 0.0041 mmPY with (inhibitors efficiency 45.2%). The FTIR spectrum, broad peak appeared in the range of 3000-3600 cm-1, which refers to the formation of hydrogen bonding of hydroxyl group. Methyl group of D-galactose also appear on 2918 cm-1 and 2850 cm-1 which attributed to =CH2 asymmetric stretch and −CH3 symmetric stretch, respectively. Carbonyl group on 1500 – 1700 cm-1 represent C=O bond of amide, and aldehyde. Peak 1097 – 1035 cm-1 which attributed to C-O were connected to the secondary and primary alcohols. The resistance value for Al5052 before and after EPD are 1.2 kΩ/cm2 after and 2.2 kΩ/cm2, respectively. Here we find that the resistance increases with the increasing concentration and time of EPD. The results cross section Al5052 within average 29.8 μm, and morphology with SEM Al5052 before EPD showed pitting corrosion. On the other hand, the image of Al5052 inhibitor coating 1.5 gr with EPD of 45 minutes shows a smooth surface and visible black lumps, suggesting Al5052 is successfully reduced a corrosion rate by the D-galactose. Our simple and robust method inferred a protection route towards a viable and physically stable green inhibitors.
FAILURE ANALYSIS OF SCREW COMPRESSOR AND ITS MODIFICATIONS Aat Safaat; Alfian Noviyanto
International Journal of Innovation in Mechanical Engineering and Advanced Materials Vol 3, No 3 (2021)
Publisher : Universitas Mercu Buana, Prodi S2 Teknik Mesin

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (261.3 KB) | DOI: 10.22441/ijimeam.v3i3.12963

Abstract

Screw compressor is one of critical equipment at many industries. Therefore, its reliability and performance shall be maintained. One problem that often arises with screw compressors is the lubrication system. This study investigates the cause of the screw compressor failure and its modification to prevent failure in the future. The failure analysis of the screw compressor was successfully conducted using the fishbone analysis diagram and visual examination. The presence of water in the oil was found due to a change of oil color. The water content analysis showed that 6% of water was found in the oil in the third month. Indeed, the presence of water has a detrimental effect on the screw compressor part, showing that corrosion has occurred in the inner part of the screw ompressor element. We found the water source comes from the air due to high humidity. Therefore, modification in the air supply is needed to prevent water contamination in the oil. The air supply modification is done using dry air at the screw compressor outlet, flowing into the breather system. The modification results showed that the oil's water content decreased significantly from 6% to 0.0035%. In addition, the vibration that occurs decreases from 80 dB to 58 dB. This shows the effectiveness of the modification process to extend the life of the tool and maintain the plant's operational continuity.