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All Journal Jurnal Matematika & Sains Journal of Mathematical and Fundamental Sciences Journal of Engineering and Technological Sciences Jurnal Kimia dan Kemasan EduChemia: Jurnal Kimia dan Pendidikan Indonesian Journal of Chemistry Jurnal Kimia dan Kemasan West Science Interdisciplinary Studies West Science Interdisciplinary Studies Bulletin of Chemical Reaction Engineering & Catalysis

Bunbun Bundjali

Chemistry Department, Bandung Institute Of Technology, Jl. Ganesha No. 10, Bandung, Indonesia

Author-ID : 244772

Humanities Astronomy Chemical Engineering, Chemistry & Bioengineering Chemistry Earth & Planetary Sciences Economics, Econometrics & Finance Education Engineering Environmental Science Materials Science & Nanotechnology Mathematics Physics Social Sciences

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UJI KUALITATIF DAN KUANTITATIF EKSTRAK Sargassum sp. DAN Gracilaria sp. SEBAGAI INHIBITOR BIO-KOROSI PADA BAJA KARBON Isriyanti Affifah; Fida Madayanti Warganegara; Bunbun Bundjali
EduChemia (Jurnal Kimia dan Pendidikan) Vol 1, No 2 (2016): Available Online in July 2016
Publisher : Department of Chemical Education Faculty of Teacher Training and Education Universitas Su

Korosi atau perkaratan logam merupakan proses oksidasi suatu logam dengan udara atau elektrolit. Udara atau elektrolit tersebut akan mengalami reduksi, sehingga proses korosi merupakan proses elektrokimia. Pada penelitian sebelumnya diketahui bahwa korosi yang disebabkan mikroorganisme pengoksidasi besi (Thiobacillus ferooxidans) memiliki peranan yang cukup signifikan terhadap kerugian ekonomi bagi industri. Lapisan biofilm yang dihasilkan mikroorganisme pada permukaan logam dapat mengubah karakteristik elektrokimia permukaan logam tersebut dan dapat menginduksi terjadinya korosi. Untuk mengatasi masalah tersebut, pada penelitian ini dilakukan ekstraksi Sargassum sp. dan Gracilaria sp. yang diduga efektif menginhibisi pertumbuhan mikroba pengoksidasi besi (Thibacillus ferooxidans) yang biasanya terdapat di bangunan bawah laut. Hasil ekstraksi Sargassum sp. dan Gracilaria sp. menggunakan pelarut metanol-kloroform (1:1) memberikan yield terhadap berat basah sebesar 44,5% dan 36,5%. Ekstrak tersebut diuji bioaktivitasnya terhadap pertumbuhan T. ferooxidans secara kualitatif (kasat mata) dan kuantitatif (metode weight-loss). Melalui kurva pertumbuhan diketahui bahwa T. ferooxidans mampu tumbuh sampai hari ke-7 dan mengalami fasa stasioner pada hari ke-8. Analisis metode weight-loss dilakukan menggunakan coupon dengan luas permukaan 3,6 cm2. Hasil analisis menunjukkan bahwa ekstrak Gracilaria sp mampu menginhibisi 29,3% lebih efektif daripada biocide komersial.

Properties of Polymer Electrolyte Membranes Prepared by Blending Sulfonated Polystyrene with Lignosulfonate Siang Tandi Gonggo; Cynthia L. Radiman; Bunbun Bundjali; I Made Arcana
Journal of Mathematical and Fundamental Sciences Vol. 44 No. 3 (2012)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/itbj.sci.2012.44.3.8

A polymer electrolyte membrane widely used in PEMFCs and DMFCs is a perfluorosulfonated membrane (the Nafion membrane). This perfluorosulfonated membrane material exhibits good chemical stability and proton conductivity, but it is very expensive and difficult to recycle. There is a high methanol crossover in DMFCs that causes a decrease in efficiency and performance of the fuel cell, so that a polymer electrolyte membrane with a low methanol crossover is needed as a substitute for the Nafion membrane. One of the materials that can be used as a polymer electrolyte membrane is the polyblends from sulfonated polystyrene-lignosulfonate (SPS-LS). Such polyblends were prepared by casting a polymer solution and characterized as polyelectrolyte membrane for DMFCs. The SPS was prepared by sulfonation of polystyrene with acetyl sulfate as the sulfonating agent. The membranes of the SPS-LS were characterized by analysis of functional groups, mechanical properties and methanol permeability. The maximum mechanical properties of the SPS-LS membrane were observed at an LS ratio of 7.5%. However, the methanol permeability of the membrane increased with the increase of the LS ratio in the SPS-LS membranes. The properties of the membranes, especially their mechanical properties and methanol permeability, were close to that of Nafion® 117 membrane, so SPS-LS membranes have high potential for use as polymer electrolyte membrane for direct methanol fuel cells.

Pelarutan Besi Selektif pada Korosi Baja Karbon dalam Larutan Buffer Asetat, Natrium Bikarbonat - CO2 Jenuh Bunbun Bundjali; N. M. Surdia; Oei Ban Liang; Bambang Ariwahjoedi
Journal of Mathematical and Fundamental Sciences Vol. 38 No. 2 (2006)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/itbj.sci.2006.38.2.5

This work has investigate conditions which allow pitting corrosion of carbon steel in acetate buffered test solutions of pH 3.82, 4.12, 5.12 and 6.12, 0.2 M NaOAc and standard brine solutions, all of which contains 100 mg/L sodium bicarbonate and saturated with CO2. Corrosion rates is determined by corrosion wheel and corrosion bubble tests, while surface morphology is observed by electron microscopy (SEM) and metallographic optical microscopy, whereas surface deterioration as well as corroded lattice structure of the steel is monitored through measurements by X-ray Diffraction (XRD) patterns. The X-ray Diffraction Patterns of corroded carbon steel in any of the above test solutions exhibit a decrease in relative intensity of 110 and 200 lattice planes and an increase in the 211 lattice plane. The extent of decrease of the diffracted X-ray intensities increases with the increase in the percentage of corroded carbon steel coupon weight loss. This might reflect a selective dissolution of iron atoms situated in both lattice planes. It is suspected that this observation is due to the fact that 211 lattice plane has the smallest percentage of atomic occupancy among the three, thus it might have the greatest chance to be inserted with carbon atoms which in turn gives a protective effect toward iron atoms against further dissolution. Although, the corrosion process starts from the surface phase, this experiment reveals that X-ray diffraction pattern of the three lattice planes could be employed as some sort of carbon steel corrosion indicator. Consequently, corrosion inhibitor performance could be deduced from its ability to maintain diffraction pattern of the initial carbon steel specimen.

Poly(urethane) synthesized from 9-ethoxy-1,10-octadecanediol obtained by modification of palm oil oleic acid Bunbun Bundjali; Muhammad Masykuri; Fitri Widya Hartanti; I Made Arcana
Journal of Mathematical and Fundamental Sciences Vol. 50 No. 1 (2018)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.math.fund.sci.2018.50.1.2

Poly(urethane) (PU) as a prepolymer was prepared by polymerization of the diol compound (9-ethoxy-1,10-octadecanediol) and 4,4-methylen-bis phenyl isocyanate (MDI) under nitrogen atmosphere at 85 °C. The 9-ethoxy-1,10-octadecanediol was obtained by several reaction steps, i.e. epoxydation of oleic acid obtained from palm oil, ring-opening of oleic acid epoxide, and reduction of oleic acid ester. All compounds obtained in this work were characterized by chemical structure analysis (FTIR and 1H NMR), supported by analysis of iodine value, acid value, and hydroxyl value determined by titration methods and thermal analysis, especially for poly(urethane). The 9-ethoxy-1,10-octadecanediol as the diol compound for preparation of poly(urethane) was analyzed by FTIR, supported by hydroxyl numbers determined by titration. Poly(urethane-urea) (PUU) was obtained by addition of ethylene diamine as chain extender to poly(urethane). The thermal stability of poly(urethane-urea) is higher than that of poly(urethane). The addition of ethylene diamine as chain extender in poly(urethane) can improve the intrinsic viscosity of polymer to form poly(urethane-urea). These results are supported by chemical structure analysis.

Synthesis of Oligosuccinimide and Evaluation of Its Corrosion Inhibition Performance on Carbon Steel in CO2-Saturated 1% NaCl Solution Muhamad Jalil Baari; Bunbun Bundjali; Deana Wahyuningrum
Journal of Mathematical and Fundamental Sciences Vol. 52 No. 2 (2020)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.math.fund.sci.2020.52.2.5

Oligosuccinimide (OSI) is an oligomer with several repeating units of succinimide. In this study, OSI was synthesized by thermal condensation between maleic anhydride and ammonium carbonate. The chemical structure of the synthesized compound was confirmed by FTIR and NMR spectroscopy as well as LC-MS characterization. Evaluation of its performance as corrosion inhibitor and the adsorption mechanism on a carbon steel surface in CO2-saturated 1% (w/v) NaCl solution was performed using electrochemical techniques (electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization) and weight-loss methods. These tests were simultaneously carried out for all fractions without separation. The EIS results showed that the inhibition efficiency (IE) of the OSI increased with increasing concentration but decreased at higher temperatures. The potentiodynamic polarization data indicated that the OSI acted as a mixed inhibitor. Adsorption of OSI on the carbon steel generally obeys the Langmuir adsorption isotherm according to curve linearity, which relates the degree of surface coverage to the inhibitor concentration. The standard Gibbs free energy of the adsorption values (âˆ†G° ads) were negative within the range of -33.14 to -38.73 kJ.mol-1, which indicates the spontaneity of the adsorption process on the carbon steel surface and that OSI molecules interacted with the carbon steel through semi-physisorption.

Synthesis and Characterization of Oligomer 4-Vinylpyridine as A Corrosion Inhibitor for Mild Steel in CO2 Saturated Brine Solution Ilim Ilim; Alan Jefferson; Wasinton Simanjuntak; Marc Jeannin; Yana Maolana Syah; Bunbun Bundjali; Buchari Buchari
Indonesian Journal of Chemistry Vol 16, No 2 (2016)
Publisher : Universitas Gadjah Mada

In this work, the oligomer of 4-vinylpyridine designated as O(4-VP) was synthesized by hydrogen peroxide initiated chain growth polymerization and characterized in terms of molecular weight and structure by matrix assisted laser desorption ionization time of flight mass spectroscopy (MALDI-TOF MS). The oligomer was tested as corrosion inhibitor of mild steel in brine solution saturated with carbon dioxide, with the main purpose to investigate the effect of inhibitor concentrations and temperatures on the inhibition activity defined in terms of corrosion rate and percent of protection. The inhibition tests were carried out using the methods of weight loss (WL) and linear polarization (LP). Characterization using MALDI-TOF MS revealed that the oligomer has the mass (m/z) in the range 200-2400, which corresponds to chain length of 2-22 repeating units. The results of corrosion rate measurements show that the corrosion rate with the use of oligomer is significantly lower than that without inhibitor, demonstrating that the oligomer functioned as effective corrosion inhibitor, while the 4-vinyl pyridine monomer was found to promote the corrosion. It was also found that the protection by the oligomer increased with increasing temperature and it was predicted the oligomer was chemically adsorbed by the surface of the metal.

KINETICS OF THE OXIDATION OF VITAMIN C Sitti Rahmawati; Bunbun Bundjali
Indonesian Journal of Chemistry Vol 12, No 3 (2012)
Publisher : Universitas Gadjah Mada

Vitamin C or ascorbic acid is needed by the human body but it is already damaged by the rise in temperature due to be oxidized to L-dehydroascorbic acid. This research aims to determine the kinetics of oxidation of ascorbic acid due to an increase if temperature (40-80 °C) and to design an ascorbic acid oxidation reaction laboratory module to be applied in the senior high school reaction kinetics curriculum. The determination of the kinetics of the oxidation of ascorbic acid applies the integral and half-change time methods, while the concentration of the remained ascorbic acid in sixty minute intervals is determined by iodimetric titration method. Decomposition of ascorbic acid was measured at 40, 50, 60, 70 and 80 °C. The results of this research indicate that at 40, 50, 60, 70 and 80 °C the kinetics of the oxidation of ascorbic acid is a first-order reaction with rate constants of 4.55 x 10-4, 5.85 x 10-4, 8.4 x 10-4, 1.1 x 10-3 and 1.015 x 10-3 min-1, respectively. Pre-exponential factor or the frequency of collisions is a factor which is a measure of the collision rate. The activation energy and the pre-exponential factor for the oxidation of ascorbic acid were found to be 20.73 kJ.mol-1 and 1.372 min-1. The procedure used in this study was modified into a laboratory module will be applied in the teaching of reaction kinetics at the senior high school level.

Performance of N,O-Carboxymethyl Chitosan as Corrosion and Scale Inhibitors in CO2 Saturated Brine Solution Muhamad Jalil Baari; Bunbun Bundjali; Deana Wahyuningrum
Indonesian Journal of Chemistry Vol 21, No 4 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.64255

The presence of salts and dissolved gas like CO2 that is carried with natural gas and crude oil along the pipeline is the main reason for corrosion and scale formation. These problems are usually resolved separately by corrosion inhibitors and scale inhibitors or acidification. Meanwhile, utilizing a compound to resolve both corrosion and scale formation has an advantage in the economic side and working time. N,O-carboxymethyl chitosan or N,O-CMCs is one of the chitosan's derivates. It is water-soluble and has different functional groups. Those properties support its capability as a complexing agent on corrosion and scale inhibitors. Synthesis of N,O-CMCs was carried out by chemical reactions between chitosan and chloroacetic acid under alkaline circumstances. N,O-CMCs product was characterized using FT-IR and 1H-NMR spectroscopy. The inhibition efficiency was analyzed by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The measurements showed that the highest efficiency of corrosion inhibition reached 63.54% when the concentration and temperature were 30 ppm and 35 °C, respectively. N,O-CMCs was classified as a mixed-type inhibitor. The adsorption mechanism of the inhibitor followed Langmuir adsorption isotherm. The static scale inhibition test informed that the optimum inhibition efficiency of N,O-CMCs reached 60.00%.

Green Synthesis of [EMIm]Ac Ionic Liquid for Plasticizing MC-based Biopolymer Electrolyte Membranes Sun Theo Constan Lotebulo Ndruru; Deana Wahyuningrum; Bunbun Bundjali; I Made Arcana
Bulletin of Chemical Reaction Engineering & Catalysis 2019: BCREC Volume 14 Issue 2 Year 2019 (August 2019)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.14.2.3074.345-357

Lithium-ion batteries (LIBs) are favorable power source devices at the last two decades, owing to high energy density, rechargeable, long life cycle, portable, safe, rechargeable, good performance and friendly environment. To support their development, in this research has been successfully prepared polymer electrolyte membrane, a main component of LIBs, based on 1-ethyl-3-methylimidazolium acetate ([EMIm]Ac) ionic liquid-plasticized methyl cellulose/lithium perchlorate (MC/LiClO4). [EMIm]Ac ionic liquid was easy synthesized by metathesis reaction between 1-ethyl-3-methylimidazolium bromide ([EMIm]Br) ionic liquid and potassium acetate (CH3COOK) at ambient temperature, for 1 hour. [EMIm]Ac ionic liquid was functional groups analyzed with Fourier Transform Infra-red (FT-IR) and structural analyzed with 1H-Nuclear Magnetic Resonance (NMR) and 13C-NMR. [EMIm]Ac ionic liquid-plasticized MC/LiClO4 biopolymer electrolyte membrane was prepared by casting solution, with [EMIm]Ac ionic liquid content, 0, 5, 10, 15, 20, 25, and 30% (w/w). Effect of 15% (w/w) [EMIm]Ac ionic liquid incorporation to MC/LiClO4 showed the best condition and selected as the optimum condition with conductivity, tensile strength, elongation break, and thermal stability of 9.160×10-3 S.cm-1, 24.19 MPa, 36.43%, ~256 and ~370 ºC, respectively. These results confirm that [EMIm]Ac ionic liquid can plasticize biopolymer electrolyte membranes of MC/LiClO4 to be appealing performances to fulfill the LIB’s separator requirement. Copyright © 2019 BCREC Group. All rights reserved

Carbon Steel Biocorrosion Inhibition by Methanol Extract Gracilaria Edulisin Seawater Fildzah Istiqomah Dukalang; Fida Madayanti Warganegara; Bunbun Bundjali
West Science Interdisciplinary Studies Vol. 1 No. 08 (2023): West Science Interdisciplinary Studies
Publisher : Westscience Press

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.58812/wsis.v1i08.149

Biocorossion in terrestrial and marinal habitats has been widely studied including the involvement of sulphate reducing bacteria which are of particular concern in the oil and gas industries. One of the sulphate reducing bacteria that triggers biocorossion is Thiobacillus ferrooxidans. This study examines the effectiveness of Gracilaria edulis macroalgae methanol extract obtained from Sayang Heulang Beach Pamengpeuk District, Garut Regency, West Java as a candidate for carbon steel biocorrosion inhibitors in seawater media. Gracilaria edulis extraction process using Folch extraction method (chloroform: methanol: phosphate buffer, 2: 1: 0.8 (v / v)). Separation of the crude methanol-water phase extract using silica column chromatography G-60 7733 with n-hexane: acetone (8: 2, 5: 5, 2: 8 (v / v)) and methanol p.a. From the results of the analysis using a UV spectrophotometer (190-400 nm) there were five combined fractions (Fraction A-Fraction E). Total content of phenolic compounds (TPC) in crude extracts of methanol-water, fraction C and fraction E respectively (410.77; 285.30; 309.51) (mg/gr GAE). The results of the qualitative test of the ability of biocorrosion inhibition of crude extracts of methanol-water phase, fraction C and fraction E by using commercial nails in solid media incubated for four days showed a decrease in the corrosion intensity on nails. Quantitative tests on the ability of biocorrosion inhibition were carried out using the weight-loss method and the results of quantitative tests showed the corrosion rate of fraction C was 12.14 ± 1.09 mpy and the fraction E was 13.94 ± 1.82 mpy for 2.5% NaCl medium while the corrosion rate of fraction C was 10.73 ± 3.63 mpy and the fraction E was 11.72 ± 0.59 mpy for seawater media. The optimum concentration test results in the inhibition showed the smallest corrosion rate fraction C was found at 0.2 mg / mL TPC levels both in 2.5% NaCl media and seawater media which each had a corrosion rate of 12.91 mpy and 8.09 mpy and the optimum concentration of fraction E was found in TPC levels of 0.4 mg / mL (2.5% NaCl media) with a corrosion rate of 14.32 mpy and TPC levels of 0.1 mg / mL (sea water medium) with a corrosion rate of 12.14 mpy. By using the optimum fraction C concentration, the results showed that the fraction C had the maximum resistance in inhibiting for 8 days (192 hours). Analysis of carbon steel plates using SEM and EDS showed that T. ferrooxidans bacterial cells formed a biofilm layer on the surface of the carbon steel plate with a localized density but mostly dominated the carbon steel plate surface and by the addition of SEM image inhibitors showed the carbon steel plate forming a layer thin that protects the metal surface and decreases the solubility of iron sulfide in water. The test results using EDS devices also detect the presence of sulfur elements and a decrease in the percentage of iron element mass on carbon steel plates without inhibitors.

Co-Authors Alan Jefferson Bambang Ariwahjoedi Bambang Ariwahjoedi Buchari Buchari Budiman Anwar Cynthia L. Radiman Cynthia Linaya Radiman Deana Wahyuningrum Dukalang, Fildzah Istiqomah Fida Madayanti Warganegara Fida Madayanti Warganegara Fida Madayanti Warganegara Fida Madayanti Warganegara Fildzah Istiqomah Dukalang Fitri Widya Hartanti Helen Mariani I Made Arcana Ilim Ilim Irah Namirah Isriyanti Affifah, Isriyanti M Hasan Marc Jeannin Muhamad Jalil Baari Muhammad Masykuri N. M. Surdia N. M. Surdia Ndruru, Sun Theo Constan Lotebulo Ni Ketut Ketis Oei Ban Liang Oei Ban Liang Rahmat Firman Septiyanto, Rahmat Firman Rifdah Hanifah Sadijah Achmad Shinta Dewi Anggraini Siang Tandi Gonggo Sitti Rahmawati Sun Theo Constan Lotebulo Ndruru Sun Theo Constan Lotebulo Ndruru Wasinton Simanjuntak Yana Maolana Syah Yayan Sunarya

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