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Influence of Electrode Distance on Electrical Energy Production of Microbial Fuel Cell using Tapioca Wastewater Harimawan, Ardiyan; Devianto, Hary; Al-Aziz, Rd. Habib R. M. T.; Shofinita, Dian; Setiadi, Tjandra
Journal of Engineering and Technological Sciences Vol 50, No 6 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

Microbial fuel cell is one alternative technology that can be used to simultaneously solve problems related with wastewater production and energy demand. This study investigates the influence of electrode distance on power density in microbial fuel cell using tapioca wastewater. Graphite sheet without metal catalyst was used for both electrodes, separated by Nafion membranes. Four variations of electrode distance were used. MFC with highest electrode distance give the highest equilibrium OCV (676 mV), while the MFC with shortest electrode distance give the highest power density (7.74 mW/m2). EIS measurement suggested that the charge transfer resistance is dominant in all MFC configuration. Wastewater COD removal were in the range of 35-46 %, which were in accordance with the power density for all MFC.

EVALUATION OF BIO-CORROSION ON CARBON STEEL BY BACILLUS MEGATERIUM IN BIODIESEL AND DIESEL OIL MIXTURE Pusparizkita, Yustina Metanoia; Schmahl, Wolfgang; Setiadi, Tjandra; Ilsemann, Bork; Reich, Mike; Devianto, Hary; Harimawan, Ardiyan
Journal of Engineering and Technological Sciences Vol 52, No 3 (2020)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2020.52.3.5

Biodiesel can act as carbon source for bacterial metabolisms, leading to corrosion of carbon steel. In this study, the corrosion of carbon steel by biodiesel blends (B15, B20, B30) was observed in the presence of Bacillus megaterium. The effect of biodiesel concentration on microorganism-induced corrosion was investigated by electrochemical impedance spectroscope (EIS), scanning electron microscope (SEM) and digital microscope. The results showed that under various biodiesel concentrations, Bacillus megaterium can grow and form biofilm on carbon steel. Based on the impedance analysis, their presence can increase the corrosion rate and cause pitting corrosion because the biofilm can change the electrochemical reactions in the metal or the interface solution and the kinetics of the anodic cathodic reactions. Also, Bacillus megaterium produces acid metabolites and can oxidize iron. Besides being influenced by Bacillus megaterium activities, the pitting formed on carbon steel depends on the biodiesel concentration. The results showed a great deal of shallow pit formation in B30, exacerbating the severity of metal roughness.

Non-linear Isotherm Models, Cadmium Kinetics, and Biosorption Thermodynamics of Dried Biomass of Native Aphanothece sp. in a Batch System Awalina Satya; Ardiyan Harimawan; Gadis Sri Haryani; Tjandra Setiadi
Journal of Engineering and Technological Sciences Vol. 49 No. 5 (2017)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2017.49.5.5

Dried biosorbent was prepared from Aphanothece sp. cyanobacteria harvested from a photobioreactor system fed with atmospheric carbon dioxide. Cadmium-ion biosorption of the prepared biosorbent from aqueous solution was characterized by non-linear (Langmuir, Freundlich and Dubinin"“Radushkevich) isotherms, non-linear kinetics (pseudo first-order and pseudo second-order) and thermodynamic analysis. The optimum conditions were pH 8.0, 30°C, 0.1 g/L biomass, and 60 min contact time. The biosorption efficiencies exceeded 90%. The low-range data (initial Cd concentration C0 = 1.09"“6.23 mg/L) and high-range data (C0 = 5.41"“83.07 mg/L) were best fitted to the Langmuir model, with maximum uptake capacities of 12.01 and 187.5 mg/g (R2 = 0.995 and 0.996). In the Dubinin"“Radushkevich isotherm model, the mean biosorption energy was 12.91 kJ/mol, suggesting that ion exchange was the working mechanism. The biosorption apparently followed pseudo second-order kinetics (R2 = 0.994"“0.999; k2 = 2.04 E-03 to 3.86 E-02 g/mg min). The biosorption process was energetically feasible (âˆ†G0 = âˆ’13.47"“âˆ’8.88 kJ/mol), exothermic (âˆ†H0 = âˆ’74.82 kJ/mol) and tended to become more ordered (âˆ†S0 = âˆ’0.204 kJ/mol K) towards the end of the process. The biosorbent was reusable through three adsorption/desorption cycles in 1 M HCl.

Influence of Electrode Distance on Electrical Energy Production of Microbial Fuel Cell using Tapioca Wastewater Ardiyan Harimawan; Hary Devianto; Rd. Habib R. M. T. Al-Aziz; Dian Shofinita; Tjandra Setiadi
Journal of Engineering and Technological Sciences Vol. 50 No. 6 (2018)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2018.50.6.7

Microbial fuel cell is one alternative technology that can be used to simultaneously solve problems related with wastewater production and energy demand. This study investigates the influence of electrode distance on power density in microbial fuel cell using tapioca wastewater. Graphite sheet without metal catalyst was used for both electrodes, separated by Nafion membranes. Four variations of electrode distance were used. MFC with highest electrode distance give the highest equilibrium OCV (676 mV), while the MFC with shortest electrode distance give the highest power density (7.74 mW/m2). EIS measurement suggested that the charge transfer resistance is dominant in all MFC configuration. Wastewater COD removal were in the range of 35-46 %, which were in accordance with the power density for all MFC.

Hydrogenated Palm Fatty Acid Distillate as Raw Materials for Magnesium Stearate Alternatives Dianika Lestari; Abdu Ravi Zakaria; Dwi Rokhmat Setiawan; Shelly Shelly; Melia Laniwati; Ardiyan Harimawan; Muhamad Insanu; Diky Mudhakir
Journal of Engineering and Technological Sciences Vol. 53 No. 3 (2021)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2021.53.3.3

Palm fatty acid distillate (PFAD) was used as raw material to produce solid lubricant, or anti-adherent, for confectionery or pharmaceutical products. To improve the degree of saturation, the PFAD was hydrogenated by using two methods: gaseous hydrogenation (GH) and catalytic transfer hydrogenation (CTH) using ammonium formate to produce hydrogenated PFAD (HPFAD). The HPFAD was saponified with MgO to produce magnesium salts of hydrogenated PFAD (Mg-HPFAD). The objective of this research was to investigate the effect of hydrogen concentration and reaction temperature on the iodine value of HPFAD and to investigate the characteristics of paracetamol tablets when using Mg-HPFAD as lubricant compared to commercial Mg-stearate. The HPFAD produced by CTH had a lower iodine value than the HPFAD produced by GH. The lowest iodine value was obtained after CTH using 3.6 M ammonium formate at 90°C. Paracetamol tablets with Mg-PFAD or Mg-HPFAD lubricant showed higher dissolution of active compounds with similar friability, frictiability, and hardness compared to paracetamol tablets with Mg-stearate.

Evaluation of Bio-Corrosion on Carbon Steel by Bacillus Megaterium in Biodiesel and Diesel Oil Mixture Yustina Metanoia Pusparizkita; Wolfgang Schmahl; Tjandra Setiadi; Bork Ilsemann; Mike Reich; Hary Devianto; Ardiyan Harimawan
Journal of Engineering and Technological Sciences Vol. 52 No. 3 (2020)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2020.52.3.5

Biodiesel can act as carbon source for bacterial metabolisms, leading to corrosion of carbon steel. In this study, the corrosion of carbon steel by biodiesel blends (B15, B20, B30) was observed in the presence of Bacillus megaterium. The effect of biodiesel concentration on microorganism-induced corrosion was investigated by electrochemical impedance spectroscope (EIS), scanning electron microscope (SEM) and digital microscope. The results showed that under various biodiesel concentrations, Bacillus megaterium can grow and form biofilm on carbon steel. Based on the impedance analysis, their presence can increase the corrosion rate and cause pitting corrosion because the biofilm can change the electrochemical reactions in the metal or the interface solution and the kinetics of the anodic cathodic reactions. Also, Bacillus megaterium produces acid metabolites and can oxidize iron. Besides being influenced by Bacillus megaterium activities, the pitting formed on carbon steel depends on the biodiesel concentration. The results showed a great deal of shallow pit formation in B30, exacerbating the severity of metal roughness.

INFLUENCE OF INITIAL pH SOLUTION ON BIOFILM FORMATION AND CORROSION OF CARBON STEEL BY Serratia marcescens Ardiyan Harimawan; Hary Devianto; Ignatius Chandra Kurniawan; Josephine Christine Utomo
Reaktor Volume 17 No. 2 Juni 2017
Publisher : Dept. of Chemical Engineering, Diponegoro University

The growth of Serratia marcescens depends on its metabolism, which is influenced by environmental factors, such as pH and temperature. The metabolic activity of Serratia marcescens may influence the corrosion of carbon steel by forming a biofilm on the metal surface. This research is focused on determining the effect of pH on carbon steel corrosion caused by Serratia marcescens. The medium used as immersion solution was a mixture of synthetic seawater and Luria-Bertani medium with a volume ratio of 4:1. The carbon steel coupons with a size of 1 cm x 1 cm were immersed in the solution with initial pH of 5, 7, and 9. The analyses of biofilm were conducted by total plate count (TPC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Biofilm was detected evenly on the metal surface and decreased with an increase in incubation pH. The biofilm consists of some functional groups, such as alcohol, alkane, amine, nitro, sulphate, carboxylic acid, and polysulfide. The analyses of the corrosion were conducted by gravimetric and X-ray diffraction (XRD). The pHs of 5 and 9 were found to give an increase in the corrosion rate. The average corrosion rate at pH variations of 5, 7, and 9 were 2.5309 g/m2.day; 2.2844 g/m2.day; and 2.9756 g/m2.day, respectively. Nevertheless, the corrosion products were not detected by XRD analysis. Keywords: biocorrosion; carbon steel; pH; seawater; Serratia marcescens Abstrak PENGARUH pH AWAL LARUTAN PADA PEMBENTUKAN BIOFILM DAN KOROSI BAJA KARBON OLEH Serratia marcescens. Laju pertumbuhan Serratia marcescens bergantung pada aktivitas metabolise mikroba, yang akan sangat dipengaruhi oleh faktor lingkungan, seperti pH dan temperatur. Aktivitas metabolisme Serratia marcescens dapat memengaruhi korosi pada baja karbon dengan membentuk lapisan biofilm pada permukaan logam. Penelitian ini bertujuan untuk menentukan efek pH pada korosi baja karbon yang disebabkan oleh Serratia marcescens. Media yang digunakan sebagai larutan perendam adalah campuran air laut sintetis dan media Luria-Bertani dengan perbandingan volume sebesar 4:1. Kupon baja karbon dengan ukuran 1 cm x 1 cm direndam dalam larutan dengan pH awal 5, 7, dan 9. Analisis lapisan biofilm dilakukan dengan total plate count (TPC), scanning electron microscopy (SEM) dan Fourier transform infrared spectroscopy (FTIR). Lapisan biofilm tumbuh secara merata pada permukaan logam dan berkurang seiring dengan peningkatan pH inkubasi. Lapisan biofilm mengandung berbagai gugus fungsional, seperti alkohol, alkana, amin, nitro, sulfat, asam karboksilat, dan polisulfida. Analisa korosi dilakukan dengan gravimetri dan X-ray diffraction (XRD). Penggunaan pH 5 dan 9 memberikan peningkatan terhadap laju korosi. Laju korosi rata-rata pada pH 5, 7, dan 9 ditentukan sebesar 2,5309 g/m2.day; 2,2844 g/m2.day; and 2,9756 g/m2.day. Namun, produk korosi tidak terdeksi oleh analisis XRD. Kata kunci: biokorosi; baja karbon; pH; air laut; Serratia marcescens

Antioxidant Activity of Vitamin E Concentrate from Magnesium Salts of Palm Fatty Acid Distillate (Mg-PFAD) Dianika Lestari; Khalisa Putri Aqilah; Salsafia Putri; Ardiyan Harimawan; Diky Mudhakir; Muhamad Insanu
Reaktor Volume 21 No. 1 March 2021
Publisher : Dept. of Chemical Engineering, Diponegoro University

Vitamin E concentrate was produced through saponification of palm fatty acid distillates (PFAD) and magnesium oxide to form Mg-PFAD, followed by three-stages vitamin E extraction with isopropanol, hexane, or ethanol. The vitamin E-rich extracts were evaporated to remove solvent and produced vitamin E concentrate. The objectives of this research were to investigate the effect of organic solvent’s types and solvent to Mg-PFAD mass ratios on vitamin E concentration, solvent selectivity, and antioxidant activity of the vitamin E concentrate. Vitamin E concentrates obtained after isopropanol extraction had vitamin E concentration of 784 ppm with vitamin E recovery of 16 mg tocopherol/100 mg tocopherol in Mg-PFAD, while vitamin E concentrates obtained after hexane extraction had vitamin E concentration of 574 ppm with vitamin E recovery of 35 mg tocopherol/100 mg tocopherol in Mg-PFAD. Isopropanol extraction produced vitamin E concentrate with the highest selectivity for vitamin E and the highest antioxidant activity of 79% IC. It was found that vitamin E concentration was not proportional to the antioxidant activity of the vitamin E concentrate.Keywords: Direct solvent extraction, palm fatty acid distillate, saponification, vitamin E, unsaponifiable matter

Dynamic and Steady Model Development of Two-Chamber Batch Microbial Fuel Cell (MFC) Ardiyan Harimawan
Reaktor Volume 21 No.4 December 2021
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/reaktor.1.1.160-169

As an alternative source of renewable energy that has piqued researchers’ interest, Microbial Fuel Cell’s (MFC) limitation of low power density requires further development. Various factors affect the performance, but performing all will be costly and time-consuming. Through a combination of dynamic and steady-state mathematical model modified from past research, effect of microbe types towards dynamic biofilm formation and stead-state OCV can be observed, followed by steady-state simulation to determine maximum power density and its’ corresponding voltage. Similarity with previous research has been observed, with maximum OCV of 838.93 mV achieved by heterotrophic biomass in 75-100 hours with biofilm thickness of 2.087 x 10-4 m, while generating maximum power density of 2050.12 mW//m2 and voltage of 408.16 mV. Lowest OCV value of 838.76 mV was observed in C. sporogenes in 450-475 hours with a biofilm thickness of 2.079 x 10-4 m, while the lowest value of maximum power density was observed in anaerobic microbial communities at 8.48 mW/m2 with voltage of 90.43 mV. Furthermore, it has been observed that variations with higher and lower results in higher stead-state OCV in the shortest amount of time, while increasing power density and its’ corresponding voltage. @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536869121 1107305727 33554432 0 415 0;}@font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-469750017 -1073732485 9 0 511 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:10.0pt; mso-ansi-font-size:10.0pt; mso-bidi-font-size:10.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-fareast-font-family:Calibri; mso-hansi-font-family:Calibri; mso-ansi-language:IN; mso-fareast-language:IN;}div.WordSection1 {page:WordSection1;}

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