66 research outputs found
The influence of biofilm formation on electricity production from tempe wastewater using tubular membraneless microbial fuel cell reactor
No full textEffect of Electrolytes and Microbial Culture Toward Electricity Generation Utilizing Tempe Wastewater in Microbial Fuel Cell
Get PDFDemand for electricity has become a crucial requirement of Indonesian society. Resources, which generate electrical energy such as fossil fuel, is predicted to run out within the next dozen years. Microbial Fuel Cell is a development of the latest technology that uses microbes to break down a substrate. This activity will cause potential difference and generate electricity. Microbes which generate electricity could be derived from pure culture and mixed culture. In this study, mixed culture of tempe wastewater microbes is used by adding electrolytes variation which are ammonium chloride-potassium chloride, potassium permanganate, and potassium persulfate in a single chamber reactor. The optimum voltage and power density are 62,09 mV and 3,01 mW/m2 when using potassium persulfate. Result of this research are compared to others research which using pure culture of L.bulgaricus by adding electrolytes variation which are potassium ferrycianide and potassium permanganate. In additional, utilization of potassium permanganat in mixed culture of tempe wastewater microbes and pure culture of L.bulgaricus are also compared to each other. The optimum voltage and power density of those comparison are 457 mV and 167,7 mW/m2 when using potassium permanganat in pure culture of L.bulgaricus
The effect of adding selective mixed culture of alternative electricity production based on tempe wastewater on tubular microbial fuel cell
No full textThe Effect of pyrolysis conditions to produce levoglucosan from rice straw
No full textThe industrial sectors that produce synthetic chemicals and and polymers rely heavily on fossil resources. Rice straw is very abundant in Indonesia and can be used as a substitute for fossil resources to produce petrochemical precursors. It is known that cellulose component is the main source for LG formation. Due to high contain of cellulose, the potential of rice straw can be transform by pyrolysis to produce bio-oils and derivative products towards levoglucosan (LG) should be developed. Levoglucosan is an important intermediate compound as it can be convert to the precursor of bio-polymer adipic acid, bio-ethanol, etc. Nowadays it’s still rarely research focused on this mechanism route producing LG through pyrolysis. LG then can run into a further reaction and produce derivative products. In order to obtain the highest yield of LG in bio-oil, a condition that may inhibit the further reaction of LG during pyrolysis takes place. The factor of biomass source and composition, temperature, and holding time (adjusted by N2 feed) most likely greatly affect the product composition formed at the end of pyrolysis. In this study, fast-pyrolysis of rice straw was performed in fixed-bed reactor (5 grams of biomass) under different temperature ranges (450 to 600 °C), N2 flow rate (1200 to 1582 ml/min) to maximize the yield of LG. The content of LG on bio-oil was measured by GC-MS instrument. The maximum yield of LG (67.78% of area) was obtained at an optimal temperature of 500°C with holding time of 1.35 s
Isolation of Methyl Laurate from Coconut Oil as Raw Material for Fatty Alcohol Sulfate
Get PDFIsolation of Methyl Laurate from Coconut Oil as Raw Material for Fatty Alcohol Sulfate. Methyl laurate is a raw or base material for many industries, including surfactant industries. In this research, coconut oil (VCO) is transesterified with methanol to produce methyl ester, using NaOH as the catalyst. Methyl laurate is then separated by method based on the difference in melting point. This research focuses at determining the effects of some variables in transesterification on the concentration of produced methyl laurate. The variables are temperature (40 oC, 50 oC, 60 oC, 80 oC), time of transesterification reaction (0,5 hour, 1 hour, 1,5 hours, 2 hours, 3 hours), and the percent weight of the catalyst NaOH (0,5 %, 1 %, 1,5 %, 2 %, 3 %). Research showed the concentration of methyl laurate increased, following the increased temperature, time, and percent weight of catalysts. Optimal conditions were acquired at reaction temperature of 60oC, reaction time of 2 hours, and percent weight of the catalyst NaOH of 2 %. Laurate acid conversion to methyl laurate that yielded from optimal conditions, after the separation based on melting point, was 55,61 %
Effect of pH, temperature and medium agitation rate in production of AA, DHA, EPA from<i>Aspergillus oryzae</i>with submerged fermentation
No full textProizvodnja biovodika u mikrobnom električnom članku s pomoću umjetno stvorene zajednice denitrificirajućih bakterija
Get PDFResearch background. This study provides insight into the use of a designed microbial community to produce biohydrogen in simple, single-chamber microbial electrolysis cells (MECs). The ability of MECs to stably produce biohydrogen relies heavily on the setup and microorganisms working inside the system. Despite having the most straightforward configuration and effectively avoiding costly membranes, single-chamber MECs are prone to competing metabolic pathways. We present in this study one possible way of avoiding this problem using characteristically defined, designed microbial consortium. Here, we compare the performance of MECs inoculated with a designed consortium to MECs operating with a naturally occurring soil consortium.
Experimental approach. We adapted a cost-effective and simple single-chamber MEC design. The MEC was gastight, 100 mL in volume, and equipped with continuous monitoring for electrical output using a digital multimeter. Microorganisms were sourced from Indonesian environmental samples, either as denitrifying bacterial isolates grouped as a designed consortium or natural soil microbiome used in its entirety. The designed consortium consisted of five species from the Pseudomonas and Acinetobacter genera. The headspace gas profile was monitored periodically with a gas chromatograph. At the end of the culture, the composition of the natural soil consortium was characterized by next generation sequencing and the growth of the bacteria on the surface of the anodes by field emission scanning electron microscopy.
Results and conclusions. We found that MEC using a designed consortium presented a better H2 production profile, with the ability of the system to maintain headspace H2 concentration relatively stable for a long time after reaching stationary growth period. In contrast, MECs inoculated with soil microbiome exhibited a strong decline in headspace H2 profile within the same time frame.
Novelty and scientific contribution. This work utilizes a designed, denitrifying bacterial consortium isolated from Indonesian environmental samples that can survive in a nitrate-rich environment. Here we propose using a designed consortium as a biological approach to avoid methanogenesis in MECs, as a simple and environmentally friendly alternative to current chemical/physical methods. Our findings offer an alternative solution to avoid the problem of H2 loss in single-chamber MECs along with optimizing biohydrogen production through bioelectrochemical routes.Pozadina istraživanja. Ovo istraživanje pruža uvid u moguću primjenu umjetno stvorene mikrobne zajednice za proizvodnju biovodika u jednostavnom električnom članku bez membrane. Stabilna proizvodnja biovodika u električnom članku uvelike ovisi o dizajnu sustava i odabiru mikroorganizama. Iako se koristi jednostavan dizajn mikrobnog električnog članka bez skupih membrana, često dolazi do kompeticije mikroorganizama uključenih u metaboličke puteve. U ovome radu je predstavljen jedan od mogućih načina rješavanja tog problema s pomoću specifične, umjetno stvorene zajednice bakterija. Uspoređen je učinak mikrobnog električnog članka inokuliranog s umjetno stvorenom zajednicom mikroorganizama s onim mikrobnog električnog članka koji sadržava prirodnu zajednicu mikroorganizama prisutnih u tlu.
Eksperimentalni pristup. Prilagodili smo jeftini i jednostavni mikrobni električni članak bez membrane, koji je nepropusan za plinove, volumena 100 mL i opremljen digitalnim multimetrom koji neprekidno prati električni izlaz. Mikroorganizmi su izolirani iz uzoraka tla u Indoneziji, i korišteni ili kao umjetno stvorena zajednica izoliranih denitrificirajućih bakterija, ili kao ukupan mikrobiom tla. Umjetno stvorena mikrobna zajednica sadržavala je pet vrsta iz rodova Pseudomonas i Acinetobacter. Periodički je praćen sastav oslobođenih plinova pomoću plinskog kromatografa. Pri završetku uzgoja je okarakteriziran sastav prirodne zajednice bakterija sekvenciranjem nove generacije, dok je njihov rast na površini anoda praćen pomoću pretražnog elektronskog mikroskopa s emisijom polja elektrona.
Rezultati i zaključci. Utvrdili smo da se s pomoću umjetno stvorene zajednice bakterija u mikrobnom električnom članku proizvede više vodika, te da je njegova koncentracija relativno stabilna dulje vrijeme nakon što je dosegnuta stacionarna faza rasta bakterija. Suprotno tome, u električnom članku inokuliranom mikrobiomom iz tla je opažen znatan pad proizvodnje vodika u istom vremenskom razdoblju.
Novina i znanstveni doprinos. U ovom je radu korištena umjetno stvorena zajednica denitrificirajućih bakterija izoliranih ih uzoraka tla iz Indonezije, koje imaju sposobnost preživljavanja u okolišu bogatom nitratom. Predlažemo primjenu umjetno stvorene zajednice, radi izbjegavanja pojave metanogeneze u mikrobnom električnom članku, kao jednostavnu i ekološki prihvatljivu alternativu proizvodnji vodika pomoću fizikalno-kemijskih metoda. Dobiveni rezultati nude rješenje problema gubitka vodika u mikrobnom električnom članku bez membrane, te optimiraju proizvodnju biovodika bioelektrokemijskim putem
Production of dry extract extracellular lipase from Aspergillus niger by solid state fermentation method to catalyze biodiesel synthesis
No full textMODEL ADSORPSI LANGMUIR GAS DINITROGEN MONOKSIDA DALAM SISTEM BIOFILTER DENGAN MEDIUM PUPUK KOMPOS
No full text LANGMUIR ADSORPTION MODEL FOR DINITROGEN MONOXIDE IN BIOFILTER SYSTEM USING COMPOST FERTILIZER MEDIUM. Nitrous oxide (N2O) is mostly emitted from various industrial processes and agricultural activities. This gas causes serious environmental problems and is considered as a dangerous pollutant. In the past, traditional control technologies, such as Selective Catalytic Reduction (SCR) and Selective Non-Catalytic Reduction (SNCR), were applied to control N2O emissions in some industries. However, these two processes required high temperatures and the use of catalysts. Economic and technical constraints in SCR and SNCR methods motivated researchers to develop new, cost-effective processes to remove N2O. Biofiltration is an emerging technology that offers a number of advantages over traditional methods of air pollution control. The purpose of this research is to modelise the biofiltration experimental results into the Langmuir adsorption model. This research is conducted in laboratory scale biofilter column, with parameters studied are effect of biofilter length and N2O gas flowrate. The result of the model is simulated into sensitivity analysis. The average Langmuir constant obtained in the model of the research is 16.006 liter/mol. Dinitrogen Monoksida (N2O) merupakan emisi dari proses industri dan kegiatan pertanian. Gas tersebut merupakan gas polutan berbahaya dan menyebabkan masalah lingkungan yang serius. Sebelumnya, teknologi kontrol tradisional seperti Selective Catalytic Reduction (SCR) dan Selective Non-Catalytic Reduction (SNCR) digunakan untuk mengontrol emisi N2O pada kegiatan-kegiatan industri. Akan tetapi, kedua proses ini membutuhkan suhu yang tinggi dan penggunaan katalis. Adanya masalah dari segi ekonomi dan teknis memotivasi peneliti untuk mengembangkan teknologi baru yang lebih murah dan efisien untuk menghilangkan N2O dari gas buangan. Pengolahan N2O secara biologis dalam proses biofiltrasi adalah salah satu alternatif ramah lingkungan yang dapat digunakan dalam pengelolaan emisi industri. Penelitian ini bertujuan untuk menggambarkan hasil biofiltrasi gas N2O dengan medium pupuk kompos dalam bentuk model adsorpsi Langmuir. Penelitian dilakukan dalam kolom biofilter skala laboratorium, dan parameter-parameter yang diteliti adalah pengaruh dari ketinggian biofilter dan laju alir gas N2O. Hasil dari pemodelan kemudian disimulasikan dalam analisis sensitivitas. Nilai konstanta Langmuir rata-rata yang didapatkan dari pemodelan penelitian ini adalah 16,006 liter/mol.</p
The effect of centrifugation speed and Chitosan-Sodium Tripolyphosphate ratio toward the nanoencapsulation of Sambiloto<i>(Andrographis paniculata)</i>for the formulation of Hepatitis B drug
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