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A two-stage continuous process was developed for improved silica extraction from rice husk. The two-stage continuous process consists of attrition ball milling and alkaline leaching methods. To find the optimum conditions for the continuous process, the effects of alkaline leaching parameters, such as the alkaline solution type and reaction conditions, on the silica extraction yield were investigated in a batch process. The use of NaOH showed a slightly higher silica yield than KOH. The optimum reaction conditions were found to be 0.2 M, 80 °C, 3 h, and 6% (w/v) for the reaction concentration, temperature, duration time, and solid content, respectively. Attrition ball milling was used to make micron-sized rice husk particles and to improve the fluidity of the rice husk slurry. The two-stage continuous process was performed using optimum conditions as determined based on the results of the batch experiment. The two-stage continuous extraction was stably operated for 80 h with an 89% silica yield. During the operation, the solid content remained consistent at 6% (w/v). The obtained silica was characterized using inductively coupled plasma–optical emission spectrometry (ICP–OES), X-ray diffraction (XRD), and the Brunauer–Emmett–Teller (BET) method.
Ji Park; Yang Gu; Seon Park; Ee Hwang; Byoung-In Sang; Jinyoung Chun; Jin Lee. Two-Stage Continuous Process for the Extraction of Silica from Rice Husk Using Attrition Ball Milling and Alkaline Leaching Methods. Sustainability 2021, 13, 7350 .
AMA StyleJi Park, Yang Gu, Seon Park, Ee Hwang, Byoung-In Sang, Jinyoung Chun, Jin Lee. Two-Stage Continuous Process for the Extraction of Silica from Rice Husk Using Attrition Ball Milling and Alkaline Leaching Methods. Sustainability. 2021; 13 (13):7350.
Chicago/Turabian StyleJi Park; Yang Gu; Seon Park; Ee Hwang; Byoung-In Sang; Jinyoung Chun; Jin Lee. 2021. "Two-Stage Continuous Process for the Extraction of Silica from Rice Husk Using Attrition Ball Milling and Alkaline Leaching Methods." Sustainability 13, no. 13: 7350.
Volatile fatty acids can be used as carbon sources for denitrification and are easily supplied as by-products from the anaerobic digestion of waste materials. Nitrification and denitrification processes were carried out in a single reactor feeding volatile fatty acids as electron donors and the changes in microbial communities in the reactor were investigated. The microbial communities in the alternating aerobic and anoxic systems were different, and their structure flexibly changed within one reactor. Bacteroidetes and Firmicutes were highly distributed during denitrification, whereas Proteobacteria was a major phylum during nitrification. In addition, in the denitrification system, the microbial community was substrate dependent. It showed the sequential nitrogen removal in one reactor and the microbial community also followed the change of environmental condition, cyclic nitrification, and denitrification.
Okkyoung Choi; Se-Jin Cha; Hyunjin Kim; Hyunook Kim; Byoung-In Sang. Dynamic Changes of Microbiome with the Utilization of Volatile Fatty Acids as Electron Donors for Denitrification. Water 2021, 13, 1556 .
AMA StyleOkkyoung Choi, Se-Jin Cha, Hyunjin Kim, Hyunook Kim, Byoung-In Sang. Dynamic Changes of Microbiome with the Utilization of Volatile Fatty Acids as Electron Donors for Denitrification. Water. 2021; 13 (11):1556.
Chicago/Turabian StyleOkkyoung Choi; Se-Jin Cha; Hyunjin Kim; Hyunook Kim; Byoung-In Sang. 2021. "Dynamic Changes of Microbiome with the Utilization of Volatile Fatty Acids as Electron Donors for Denitrification." Water 13, no. 11: 1556.
The impact of attrition ball-mill pretreatment on food waste particle size, soluble chemical oxygen demand (SCOD), biochemical methane potential, and microbial community during anaerobic digestion was investigated based on milling speed and time. The uniformity of particle size improved with increasing milling speed and time. The SCOD of the pretreated samples increased to 4%, 7%, and 17% at the speeds of 150, 225, and 300 rpm, respectively, compared to the control. Milling time did not significantly change the SCOD. The cumulative methane productions of 430, 440, and 490 mL/g-VS were observed at the speeds of 150, 225, and 300 rpm, respectively, while the untreated sample exhibited the cumulative methane production of 390 mL/g-VS. Extended milling time did not improve methane production much. When the milling times of 10, 20, and 30 min were applied with the milling speed fixed at 300 rpm, the methane productions of 490, 510, and 500 mL/g-VS were observed respectively. Ball-mill pretreatment also increased the total volatile fatty acids. During the anaerobic digestion (AD) of ball-mill treated food waste, acetoclastic methanogens predominated, with a relative abundance of 48–49%. Interestingly, hydrogenotrophic methanogens were 1.6 times higher in the pretreated samples than those in the control. These results showed the potential of attrition ball milling as a food waste pretreatment for improving methane production.
Yang Gu; Seon Park; Ji Park; Byoung-In Sang; Byoung Jeon; Hyunook Kim; Jin Lee. Impact of Attrition Ball-Mill on Characteristics and Biochemical Methane Potential of Food Waste. Energies 2021, 14, 2085 .
AMA StyleYang Gu, Seon Park, Ji Park, Byoung-In Sang, Byoung Jeon, Hyunook Kim, Jin Lee. Impact of Attrition Ball-Mill on Characteristics and Biochemical Methane Potential of Food Waste. Energies. 2021; 14 (8):2085.
Chicago/Turabian StyleYang Gu; Seon Park; Ji Park; Byoung-In Sang; Byoung Jeon; Hyunook Kim; Jin Lee. 2021. "Impact of Attrition Ball-Mill on Characteristics and Biochemical Methane Potential of Food Waste." Energies 14, no. 8: 2085.
Antimicrobial air filters are required to protect humans from the risk of secondary bioaerosol pollution as well as airborne particles. Three plant extracts (tea-tree oil, rosemary, and garlic) were selected to replace antimicrobial chemicals in air filters. The antimicrobial activity of plant extracts was investigated using Micrococcus luteus and Escherichia coli. Phytochemicals present in the three plant extracts were identified using a gas chromatograph coupled with a mass spectrometer. The extracts were spray-coated on polyethylene terephthalate filter surfaces using silicate polymeric coating and evaluated via X-ray photoelectron spectroscopy and a scanning electron microscope with energy dispersive spectroscopy. After coating, an increase of 9.1% in the pressure drop was observed. The strain Micrococcus luteus was used to evaluate the antimicrobial activity of the air filter. After bioaerosol exposure, the tea-tree oil-coated filters immediately induced M. luteus cell inactivation (40–55%), whereas the rosemary and garlic coated filters did not. However, 48 h after exposure, a significant M. luteus inactivation of 99.99%, 99.0%, and 99.9% was recorded for concentrations of 2.89, 6.73, and 11.51 mg/cm2 for the tea-tree, rosemary, and garlic extracts, respectively. The coated filters exhibited high antimicrobial activity, thereby indicating significant potential for application as self-cleaning air filters.
Ha Ram Byun; Seon Young Park; Ee Taek Hwang; Byoung In Sang; Jiho Min; Daekyung Sung; Won Il Choi; Sunghyun Kim; Jin Hyung Lee. Antimicrobial Air Filter Coating with Plant Extracts Against Airborne Microbes. Applied Sciences 2020, 10, 9120 .
AMA StyleHa Ram Byun, Seon Young Park, Ee Taek Hwang, Byoung In Sang, Jiho Min, Daekyung Sung, Won Il Choi, Sunghyun Kim, Jin Hyung Lee. Antimicrobial Air Filter Coating with Plant Extracts Against Airborne Microbes. Applied Sciences. 2020; 10 (24):9120.
Chicago/Turabian StyleHa Ram Byun; Seon Young Park; Ee Taek Hwang; Byoung In Sang; Jiho Min; Daekyung Sung; Won Il Choi; Sunghyun Kim; Jin Hyung Lee. 2020. "Antimicrobial Air Filter Coating with Plant Extracts Against Airborne Microbes." Applied Sciences 10, no. 24: 9120.
The world of bioplastics has expanded rapidly in recent decades, and the new waste stream generated is creating major barriers to waste processing. Anaerobic co-digestion is to be considered one of the best options for the efficient processing of bioplastic waste due to its minimal space requirements, lower degrees of environmental pollution, and renewable energy generation. The higher carbon to nitrogen (C/N) ratio of bioplastics poses a challenge to anaerobic digestion, but co-digestion with lower C/N ratio biowastes can efficiently degrade bioplastics and improve biogas production in the system. In the future, the collection of organic waste in biodegradable plastic bags makes the waste management process easier for anaerobic digestion plants. The present review paper discusses current trends of bioplastic usage, degradation strategies, and the potential of anaerobic co-digestion for waste management with improved energy production in anaerobic digesters.
Amith Abraham; Hyojung Park; Okkyoung Choi; Byoung-In Sang. Anaerobic co-digestion of bioplastics as a sustainable mode of waste management with improved energy production – A review. Bioresource Technology 2020, 322, 124537 .
AMA StyleAmith Abraham, Hyojung Park, Okkyoung Choi, Byoung-In Sang. Anaerobic co-digestion of bioplastics as a sustainable mode of waste management with improved energy production – A review. Bioresource Technology. 2020; 322 ():124537.
Chicago/Turabian StyleAmith Abraham; Hyojung Park; Okkyoung Choi; Byoung-In Sang. 2020. "Anaerobic co-digestion of bioplastics as a sustainable mode of waste management with improved energy production – A review." Bioresource Technology 322, no. : 124537.
The accumulation of short-chain carboxylic acids (SCCAs), such as acetic acid (C2), propionic acid (C3), butyric acid (C4), and valeric acid (C5), produced by acetogens in the anaerobic digestion (AD) process hampers the maintenance of stable AD processes in biomethane production. The conversion of various SCCAs to the corresponding alcohols can be a good solution not only for utilizing abandoned or harmful SCCAs and producing useful alcohols but also for increasing the efficiency of the biogas production process. ACT01_02765 (acyl-CoA transferase) from Megasphaera hexanoica quickly and easily converted C2-C8 carboxylic acids into the corresponding alcohols in Escherichia coli with AdhE2 (alcohol dehydrogenase) from Clostridium acetobutylicum. E. coli (ACT01_02765 and AdhE2) converted carboxylic acids to the corresponding alcohols with a conversion yield that was approximately 40 times higher and a conversion rate that was approximately 10–50 times faster than those of E. coli (Ptb-Buk and AdhE2). The enzymatic machinery in E. coli (ACT01_02765 and AdhE2) is effective for carboxylic acids of different carbon chain lengths, resulting in the production of propanol, butanol, pentanol, hexanol, heptanol, and octanol.
Hyojung Park; Byoung Seung Jeon; Byoung-In Sang. Efficient, Simple Production of Corresponding Alcohols from Supplemented C2-C8 Carboxylic Acids in Escherichia coli Using Acyl-CoA Transferase from Megasphaera hexanoica. Biotechnology and Bioprocess Engineering 2020, 25, 599 -606.
AMA StyleHyojung Park, Byoung Seung Jeon, Byoung-In Sang. Efficient, Simple Production of Corresponding Alcohols from Supplemented C2-C8 Carboxylic Acids in Escherichia coli Using Acyl-CoA Transferase from Megasphaera hexanoica. Biotechnology and Bioprocess Engineering. 2020; 25 (4):599-606.
Chicago/Turabian StyleHyojung Park; Byoung Seung Jeon; Byoung-In Sang. 2020. "Efficient, Simple Production of Corresponding Alcohols from Supplemented C2-C8 Carboxylic Acids in Escherichia coli Using Acyl-CoA Transferase from Megasphaera hexanoica." Biotechnology and Bioprocess Engineering 25, no. 4: 599-606.
Butyric acid, a short chain carboxylic acid with diverse usages, is produced by Clostridia fermentation. In the industrial scale production of butyric acid, its separation and recovery from fermentation broth requires energy-intensive processes. To reduce the product recovery costs, it is necessary to convert butyric acid into a chemical with a much higher partition coefficient in the hydrophobic extractants than butyric acid. Butyl butyrate, with an excellent partition coefficient to tetradecane, can be produced by the enzymatic conversion of butyric acid via esterification. Moreover, butyl butyrate can be used as a valuable fuel source and additive in the food, cosmetic, and pharmaceutical industries. Novozyme 435, Candida antarctica lipase B immobilized on acrylic resin, and tetradecane were used as the enzyme and extractant, respectively. A high-pressure CO2-facilitated reactor was used to temporarily drop the pH of the fermentation broth so that the enzymatic reaction could be activated. The in situ removal of butyric acid and simultaneous production of butyl butyrate were processed continuously during fermentation. To optimize the enzymatic reaction, it was necessary to maintain a temperature of 40°C at 50 bar and an optimal molar ratio of substrate. In the extractive fermentation, 11.6 g/L butyl butyrate was produced with a productivity of 0.77 g/L/h from butyrate produced through fermentation. This process is expected to be able to extract carboxylic acids with more diverse carbon lengths in ester form.
Jaesung Chun; Byoung-In Sang. Enzymatic Esterification under High-pressure CO2 Conditions for in situ Recovery of Butyric Acid from Anaerobic Fermenters. Biotechnology and Bioprocess Engineering 2020, 25, 616 -622.
AMA StyleJaesung Chun, Byoung-In Sang. Enzymatic Esterification under High-pressure CO2 Conditions for in situ Recovery of Butyric Acid from Anaerobic Fermenters. Biotechnology and Bioprocess Engineering. 2020; 25 (4):616-622.
Chicago/Turabian StyleJaesung Chun; Byoung-In Sang. 2020. "Enzymatic Esterification under High-pressure CO2 Conditions for in situ Recovery of Butyric Acid from Anaerobic Fermenters." Biotechnology and Bioprocess Engineering 25, no. 4: 616-622.
Bacterial nanocellullose (BNC) is a versatile matrix for designing and incorporating three-dimensional functional nanomaterials for different applications. The present study describes the fabrication of a flexible catalytic electrode for hydrogen evolution reaction using nanocellulose derived from Komagataeibacter sucrofermentans. By simple electroless deposition, the BNC is transformed into a conductive flexible substrate. On the subsequent electrodeposition process in a solution of Ni and Mo, the conductive BNC made into an active electrode for hydrogen (H2) generation. The highly nano-porous architecture and binder-free nature of the BNC electrode enhances the surface active sites and exhibit an excellent catalytic hydrogen production in alkaline conditions. Electrochemical studies show that the NiMoO4/BNC electrode to achieve a current density of 10 mA cm−2 requires an overpotential of 109 mV with a Tafel slope of 170 mV dec−1 in 1 M KOH. Moreover, the electrode demonstrates good stability in the alkaline medium during prolonged electrolysis for 48 h. The study offers the fabrication of BNC based electrode for efficient electrocatalytic hydrogen production and promoting the usage of green materials in renewable energy technologies.
Amith Abraham; Vasanth Rajendiran Jothi; Jungyoup Lee; Sung-Chul Yi; Byoung-In Sang. Bacterial nanocellulose as a green and flexible electrode matrix for efficient hydrogen evolution reaction in alkaline conditions. Cellulose 2020, 27, 1 -12.
AMA StyleAmith Abraham, Vasanth Rajendiran Jothi, Jungyoup Lee, Sung-Chul Yi, Byoung-In Sang. Bacterial nanocellulose as a green and flexible electrode matrix for efficient hydrogen evolution reaction in alkaline conditions. Cellulose. 2020; 27 (14):1-12.
Chicago/Turabian StyleAmith Abraham; Vasanth Rajendiran Jothi; Jungyoup Lee; Sung-Chul Yi; Byoung-In Sang. 2020. "Bacterial nanocellulose as a green and flexible electrode matrix for efficient hydrogen evolution reaction in alkaline conditions." Cellulose 27, no. 14: 1-12.
: Chlorination is the preferred method to control biofouling in a power plant cooling system due to its comparative effectiveness and low cost. If a power plant is located in a coastal area, chlorine can be electrochemically generated in-situ using seawater, which is called in-situ electro-chlorination; this approach has several advantages including fewer harmful chlorination byproducts and no need for chlorine storage. Nonetheless, this electrochemical process is still in its infancy in practice. In this study, a parallel first-order kinetics was applied to simulate chlorine decay in a pilot-scale cooling system. Since the decay occurs along the water-intake pipe, the kinetics was incorporated into computational fluid dynamics (CFD) codes, which were subsequently applied to simulate chlorine behavior in the pipe. The experiment and the simulation data indicated that chlorine concentrations along the pipe wall were incremental, even under the condition where a strong turbulent flow was formed. The fact that chlorine remained much more concentrated along the pipe surface than in the middle allowed for the reduction of the overall chlorine demand of the system based on the electro-chlorination. The cooling system, with an in-situ electro-chlorination, consumed only 1/3 of the chlorine dose demanded by the direct injection method. Therefore, it was concluded that in-situ electro-chlorination could serve as a cost-effective and environmentally friendly approach for biofouling control at power plants on coastal areas.
Jongchan Yi; JongHun Lee; Mohd Amiruddin Fikri; Byoung-In Sang; Hyunook Kim. Application of Computational Fluid Dynamics in Chlorine-Dynamics Modeling of In-Situ Chlorination Systems for Cooling Systems. Applied Sciences 2020, 10, 4455 .
AMA StyleJongchan Yi, JongHun Lee, Mohd Amiruddin Fikri, Byoung-In Sang, Hyunook Kim. Application of Computational Fluid Dynamics in Chlorine-Dynamics Modeling of In-Situ Chlorination Systems for Cooling Systems. Applied Sciences. 2020; 10 (13):4455.
Chicago/Turabian StyleJongchan Yi; JongHun Lee; Mohd Amiruddin Fikri; Byoung-In Sang; Hyunook Kim. 2020. "Application of Computational Fluid Dynamics in Chlorine-Dynamics Modeling of In-Situ Chlorination Systems for Cooling Systems." Applied Sciences 10, no. 13: 4455.
Caproic acid (CA) was produced by Megasphaera elsdenii T81 with Jerusalem artichoke tubers (JA) as a feedstock. More CA was produced under the medium with the acid hydrolysate of JA than the comparative medium with a carbon composition similar to that of JA. CA was produced up to 13.0 g/L and 0.52 g/L/h with extractive fermentation using a mixed solvent of alamine 336 in oleyl alcohol at 37 °C. The JA cost to produce 1 ton of CA is only 505 USD, which is much lower than that required for purchasing sucrose (860 USD) in CA production. As a result of the analysis performed using SuperPro Designer, including the cost of distillation to obtain pure CA, the estimated production cost for CA from dry JA is 1869 USD/ton CA at the production scale of 2000 ton/year, which is lower than the current market price for petroleum-derived CA (~2500 USD/ton).
Hyunjin Kim; Okkyoung Choi; Byoung Seung Jeon; Woo-Seok Choe; Byoung-In Sang. Impact of feedstocks and downstream processing technologies on the economics of caproic acid production in fermentation by Megasphaera elsdenii T81. Bioresource Technology 2020, 301, 122794 .
AMA StyleHyunjin Kim, Okkyoung Choi, Byoung Seung Jeon, Woo-Seok Choe, Byoung-In Sang. Impact of feedstocks and downstream processing technologies on the economics of caproic acid production in fermentation by Megasphaera elsdenii T81. Bioresource Technology. 2020; 301 ():122794.
Chicago/Turabian StyleHyunjin Kim; Okkyoung Choi; Byoung Seung Jeon; Woo-Seok Choe; Byoung-In Sang. 2020. "Impact of feedstocks and downstream processing technologies on the economics of caproic acid production in fermentation by Megasphaera elsdenii T81." Bioresource Technology 301, no. : 122794.
We introduced a new elastic interface layer (EIL), (Li2S)0.75(P2S5)0.25 glass, in all-solid-state batteries (ASSBs) to improve the solid-state interfacial structure, and analyzed its structural evolution in electrochemical charge/discharge cycles. This EIL had a lower bulk modulus, thereby providing good powder processability and high mechanical deformability against volume changes of the electrode. Compared to a cell configuring EIL, the reference cell exhibited a considerable increase in the electrolyte resistance; moreover, a new resistance component was identified in the high-frequency region (500–50 kHz). This high-resistance component resulting from interfacial deterioration such as metal fragmentation and micropore formation was successfully suppressed by applying a mechanically deformable EIL. We believe that this study would provide insights into the application of EIL for configuring a stable interface with a metallic electrode in ASSBs.
Sungjun Choi; Minjae Jeon; Wo Dum Jung; Sungeun Yang; Sangbaek Park; Ho-Il Ji; Jong-Ho Lee; Byung-Kook Kim; Byoung-In Sang; Hyoungchul Kim. Robust solid-state interface with a deformable glass interlayer in sulfide-based all-solid-state batteries. Solid State Ionics 2020, 346, 115217 .
AMA StyleSungjun Choi, Minjae Jeon, Wo Dum Jung, Sungeun Yang, Sangbaek Park, Ho-Il Ji, Jong-Ho Lee, Byung-Kook Kim, Byoung-In Sang, Hyoungchul Kim. Robust solid-state interface with a deformable glass interlayer in sulfide-based all-solid-state batteries. Solid State Ionics. 2020; 346 ():115217.
Chicago/Turabian StyleSungjun Choi; Minjae Jeon; Wo Dum Jung; Sungeun Yang; Sangbaek Park; Ho-Il Ji; Jong-Ho Lee; Byung-Kook Kim; Byoung-In Sang; Hyoungchul Kim. 2020. "Robust solid-state interface with a deformable glass interlayer in sulfide-based all-solid-state batteries." Solid State Ionics 346, no. : 115217.
The inclusion of a pretreatment step in anaerobic digestion processes increases the digestibility of lignocellulosic biomass and enhances biogas yields by promoting lignin removal and the destruction of complex biomass structures. The increase in surface area enables the efficient interaction of microbes or enzymes, and a reduction in cellulose crystallinity improves the digestion process under anaerobic conditions. The pretreatment methods may vary based on the type of the lignocellulosic biomass, the nature of the subsequent process and the overall economics of the process. An improved biogas production by 1200% had been reported when ionic liquid used as pretreatment strategy for anaerobic digestion. The different pretreatment techniques used for lignocellulosic biomasses are generally grouped into physical, chemical, physicochemical, and biological methods. These four modes of pretreatment on lignocellulosic biomass and their impact on biogas production process is the major focus of this review article.
Amith Abraham; Anil K. Mathew; Hyojung Park; Okkyoung Choi; Raveendran Sindhu; Binod Parameswaran; Ashok Pandey; Jung Han Park; Byoung-In Sang. Pretreatment strategies for enhanced biogas production from lignocellulosic biomass. Bioresource Technology 2020, 301, 122725 .
AMA StyleAmith Abraham, Anil K. Mathew, Hyojung Park, Okkyoung Choi, Raveendran Sindhu, Binod Parameswaran, Ashok Pandey, Jung Han Park, Byoung-In Sang. Pretreatment strategies for enhanced biogas production from lignocellulosic biomass. Bioresource Technology. 2020; 301 ():122725.
Chicago/Turabian StyleAmith Abraham; Anil K. Mathew; Hyojung Park; Okkyoung Choi; Raveendran Sindhu; Binod Parameswaran; Ashok Pandey; Jung Han Park; Byoung-In Sang. 2020. "Pretreatment strategies for enhanced biogas production from lignocellulosic biomass." Bioresource Technology 301, no. : 122725.
Here, we describe the complete genome of Methanothermobacter sp. strain KEPCO-1, a thermophilic and hydrogenotrophic methanogen that was isolated from an anaerobic digester in Seoul, Republic of Korea. The genome of KEPCO-1 shares 96.98% of its sequence with Methanothermobacter marburgensis strain DSM 2133 and consists of 1,741,029 bp, with 1,822 protein-coding genes, 44 noncoding RNAs, and a GC content of 48.47%. The development of this genome will facilitate future genomic studies of KEPCO-1.
Byoung Seung Jeon; Hyunjin Kim; Young Wook Go; Young Gook Kim; Ji Sun Joo; Okkyoung Choi; Byoung-In Sang. Complete Genomic Sequence of the Thermophilic and Hydrogenotrophic Methanogen Methanothermobacter sp. Strain KEPCO-1. Microbiology Resource Announcements 2020, 9, 1 .
AMA StyleByoung Seung Jeon, Hyunjin Kim, Young Wook Go, Young Gook Kim, Ji Sun Joo, Okkyoung Choi, Byoung-In Sang. Complete Genomic Sequence of the Thermophilic and Hydrogenotrophic Methanogen Methanothermobacter sp. Strain KEPCO-1. Microbiology Resource Announcements. 2020; 9 (1):1.
Chicago/Turabian StyleByoung Seung Jeon; Hyunjin Kim; Young Wook Go; Young Gook Kim; Ji Sun Joo; Okkyoung Choi; Byoung-In Sang. 2020. "Complete Genomic Sequence of the Thermophilic and Hydrogenotrophic Methanogen Methanothermobacter sp. Strain KEPCO-1." Microbiology Resource Announcements 9, no. 1: 1.
Methane production was carried out in two different types of reactors using a thermophilic and hydrogenotrophic methanogen, Methanothermobacter sp. KEPCO-1, which converts hydrogen and carbon dioxide into methane at 60 °C. The two reactors used for methane production were stirred-tank reactor (ST) and a bubble column reactor (BC), which were selected because they can provide a good comparison between the medium agitation type and gas–liquid mass transfer. The specific growth rate of KEPCO-1 in the ST and BC was 0.03 h−1 and 0.07 h−1, respectively. The methane conversion rate increased to 77.8 L/L/d in the ST and 19.8 L/L/d in the BC. To prevent the dilution of nutrients in the medium by the water generated during the hydrogenotrophic methanation reaction, a membrane distillation (MD) process was applied to selectively remove water from the culture medium. The MD process selectively removed only water from the medium. Fouling by KEPCO-1 had a negligible effect on flux and showed a high removal performance flux of 16.3 ± 3.1 L/m2/h. By operating the MD process in conjunction with the hydrogenotrophic methanation process, it is possible to prevent the dilution of the nutrients in the medium by the water generated during the methanation process, thereby maintaining stable microbial growth and methanation activity.
Okkyoung Choi; Minjeong Kim; Youngwook Go; Moon-Gi Hong; Bomin Kim; Yonghyun Shin; Sangho Lee; Young Gook Kim; Ji Sun Joo; Byoung Seung Jeon; Byoung-In Sang. Selective Removal of Water Generated during Hydrogenotrophic Methanation from Culture Medium Using Membrane Distillation. Energies 2019, 12, 4130 .
AMA StyleOkkyoung Choi, Minjeong Kim, Youngwook Go, Moon-Gi Hong, Bomin Kim, Yonghyun Shin, Sangho Lee, Young Gook Kim, Ji Sun Joo, Byoung Seung Jeon, Byoung-In Sang. Selective Removal of Water Generated during Hydrogenotrophic Methanation from Culture Medium Using Membrane Distillation. Energies. 2019; 12 (21):4130.
Chicago/Turabian StyleOkkyoung Choi; Minjeong Kim; Youngwook Go; Moon-Gi Hong; Bomin Kim; Yonghyun Shin; Sangho Lee; Young Gook Kim; Ji Sun Joo; Byoung Seung Jeon; Byoung-In Sang. 2019. "Selective Removal of Water Generated during Hydrogenotrophic Methanation from Culture Medium Using Membrane Distillation." Energies 12, no. 21: 4130.
The caproate-producing bacterium, Megasphaera hexanoica, metabolizes fructose to produce C2~C8 carbon-chain carboxylic acids using various electron acceptors. In particular, odd-chain carboxylic acids (OCCAs) such as valerate (C5) and heptanoate (C7), were produced at relatively high concentrations upon propionate supplementation. Using a statistical experimental design method, the optimal culture medium was established for the selective production of OCCAs among the total produced acids. In a medium containing 2.42 g L−1 sodium acetate and 18.91 g L−1 sodium propionate, M. hexanoica produced 9.48 g L−1 valerate, 2.48 g L−1 heptanoate, and 0.12 g L−1 caproate. To clarify the metabolism of the exogenous added propionate for OCCAs production, 13C tracer experiments were performed by supplementing the culture broth with [1,2,3-13C3] propionate. The metabolites analysis based on mass spectrometry showed that the propionate was only used to produce valerate and heptanoate without being participated in other metabolic pathways. Furthermore, the carbon elongation pathway in M. hexanoica was explained by the finding that the incorporation of propionate and acetate in the produced valerate occurred in only one orientation.
Hyunjin Kim; Byoung Seung Jeon; Byoung-In Sang. An Efficient New Process for the Selective Production of Odd-Chain Carboxylic Acids by Simple Carbon Elongation Using Megasphaera hexanoica. Scientific Reports 2019, 9, 1 -10.
AMA StyleHyunjin Kim, Byoung Seung Jeon, Byoung-In Sang. An Efficient New Process for the Selective Production of Odd-Chain Carboxylic Acids by Simple Carbon Elongation Using Megasphaera hexanoica. Scientific Reports. 2019; 9 (1):1-10.
Chicago/Turabian StyleHyunjin Kim; Byoung Seung Jeon; Byoung-In Sang. 2019. "An Efficient New Process for the Selective Production of Odd-Chain Carboxylic Acids by Simple Carbon Elongation Using Megasphaera hexanoica." Scientific Reports 9, no. 1: 1-10.
The present study evaluated the nitrate removal efficiency of a potent aerobic denitrifying bacterium in different bioreactor systems. The isolated bacterial strain was characterized as Pseudomonas sp. on the basis of biochemical and 16S rDNA sequence analysis. The strain showed an unusual ability of nitrate removal in both aerobic and anaerobic conditions, with the highest efficiency in aerobic conditions. Denitrification efficiency was assessed and at low nitrate concentrations (50 mg/L), complete removal has occurred within 24 hours and in high concentration (216 mg/L) removal was on 48th hours of cultivation. The bacterial growth pattern was similar in all tested nitrate concentrations and the tolerant strain JN5 could perform the aerobic denitrification at higher concentrations. In a fermenter with an initial nitrate concentration of 100 mg/L, complete removal was observed within 24 hours of incubation. Around 50% of nitrate removal was achieved during the logarithmic growth phase of the bacterium and the remaining portion in a stationary phase under high dissolved oxygen conditions. The aerobic denitrifying efficiency of the newly isolated bacterial strain JN5 was improved in a combined and packed bed reactor system with circulating batch and continuous process operations. The isolate JN5 can be efficiently used as an aerobic denitrifier in a bioaugmentation based water purification system and the combinations of reactor system can improve the performance of nitrate removal by aerobic denitrifying microorganism.
Kyoung-In Jun; Amith Abraham; Okkyoung Choi; Byoung-In Sang. Aerobic denitrification by a novel Pseudomonas sp. JN5 in different bioreactor systems. Water-Energy Nexus 2019, 2, 37 -45.
AMA StyleKyoung-In Jun, Amith Abraham, Okkyoung Choi, Byoung-In Sang. Aerobic denitrification by a novel Pseudomonas sp. JN5 in different bioreactor systems. Water-Energy Nexus. 2019; 2 (1):37-45.
Chicago/Turabian StyleKyoung-In Jun; Amith Abraham; Okkyoung Choi; Byoung-In Sang. 2019. "Aerobic denitrification by a novel Pseudomonas sp. JN5 in different bioreactor systems." Water-Energy Nexus 2, no. 1: 37-45.
We determined the potential of three mechanical pulverizers—a continuous ball mill (CBM), an air classifier mill (ACM), and a high-speed mill (HSM)—in the continuous pretreatment of corn stover. The mean diameters of the pulverized biomasses were not significantly different in the three cases, and the glucose yields from the CBM-, ACM-, and HSM-pulverized samples were 29%, 49%, and 44%, respectively. The energy requirements and process capacities for the ACM and HSM were similar. We conclude that the ACM and HSM could be used in the continuous pretreatment of corn stover and would be useful in biofuel production.
Yang Mo Gu; Sunghyun Kim; Daekyung Sung; Byoung-In Sang; Jin Hyung Lee. Feasibility of Continuous Pretreatment of Corn Stover: A Comparison of Three Commercially Available Continuous Pulverizing Devices. Energies 2019, 12, 1422 .
AMA StyleYang Mo Gu, Sunghyun Kim, Daekyung Sung, Byoung-In Sang, Jin Hyung Lee. Feasibility of Continuous Pretreatment of Corn Stover: A Comparison of Three Commercially Available Continuous Pulverizing Devices. Energies. 2019; 12 (8):1422.
Chicago/Turabian StyleYang Mo Gu; Sunghyun Kim; Daekyung Sung; Byoung-In Sang; Jin Hyung Lee. 2019. "Feasibility of Continuous Pretreatment of Corn Stover: A Comparison of Three Commercially Available Continuous Pulverizing Devices." Energies 12, no. 8: 1422.
A thermophilic bioelectrochemical system was operated with mixed culture at 60℃, while introducing only carbon dioxide. Methane production was initially observed in a membrane-less single chamber without a electron mediator, but eventually acetate was also found as 10.5 g/L after 137 days of operation. Comparing the microbial communities before and after the electricity supply using next-generation sequencing technology, acetoclastic methanogens such as Methanosaeta concilii were increased, and this result also indicates the production of acetate in bioelectrochemical CO2 conversion system. With the advent of sulfate-reducing bacteria, Desulfotomaculum peckii was considered to be an acetate production promoter. These high production results for both methane and acetate can be applied to CO2 storage using excess electricity for value-added chemicals.
Hyojeong Song; Okkyoung Choi; Ashok Pandey; Young Gook Kim; Ji Sun Joo; Byoung-In Sang. Simultaneous production of methane and acetate by thermophilic mixed culture from carbon dioxide in bioelectrochemical system. Bioresource Technology 2019, 281, 474 -479.
AMA StyleHyojeong Song, Okkyoung Choi, Ashok Pandey, Young Gook Kim, Ji Sun Joo, Byoung-In Sang. Simultaneous production of methane and acetate by thermophilic mixed culture from carbon dioxide in bioelectrochemical system. Bioresource Technology. 2019; 281 ():474-479.
Chicago/Turabian StyleHyojeong Song; Okkyoung Choi; Ashok Pandey; Young Gook Kim; Ji Sun Joo; Byoung-In Sang. 2019. "Simultaneous production of methane and acetate by thermophilic mixed culture from carbon dioxide in bioelectrochemical system." Bioresource Technology 281, no. : 474-479.
We demonstrated the use of three-dimensional (3D) atom-probe tomography (APT) for analyzing the electrochemical lithiation/delithiation in the composite cathodes of all-solid-state batteries (ASSBs). 3D APT provides direct determination of the Li-ion contents, having difficult by X-ray excitation. Compared with various cathodes, they showed a significant variation in the Li-ion concentration during lithiation/delithiation because of the poor solid-to-solid interfaces, which is an inherent problem in ASSBs. In addition, the loss of transition-metal content was quantitatively verified. We have confirmed that our APT can be effectively applied to ASSB systems and it would be provide a deeper understanding of electrochemistry in ASSBs.
Sungjun Choi; Bin-Na Yun; Wo Dum Jung; Tae Hyun Kim; Kyung-Yoon Chung; Ji-Won Son; Byoung-In Sang; Hun-Gi Jung; Hyoungchul Kim. Tomographical analysis of electrochemical lithiation and delithiation of LiNi0.6Co0.2Mn0.2O2 cathodes in all-solid-state batteries. Scripta Materialia 2019, 165, 10 -14.
AMA StyleSungjun Choi, Bin-Na Yun, Wo Dum Jung, Tae Hyun Kim, Kyung-Yoon Chung, Ji-Won Son, Byoung-In Sang, Hun-Gi Jung, Hyoungchul Kim. Tomographical analysis of electrochemical lithiation and delithiation of LiNi0.6Co0.2Mn0.2O2 cathodes in all-solid-state batteries. Scripta Materialia. 2019; 165 ():10-14.
Chicago/Turabian StyleSungjun Choi; Bin-Na Yun; Wo Dum Jung; Tae Hyun Kim; Kyung-Yoon Chung; Ji-Won Son; Byoung-In Sang; Hun-Gi Jung; Hyoungchul Kim. 2019. "Tomographical analysis of electrochemical lithiation and delithiation of LiNi0.6Co0.2Mn0.2O2 cathodes in all-solid-state batteries." Scripta Materialia 165, no. : 10-14.
Exploring efficient electrocatalyst for H2 evolution reaction (HER) and replacing the noble metal-based catalysts with inexpensive non-noble metal-based HER catalyst is of great importance for the practicality of hydrogen powered clean technologies. Here, we explore a new class of metal organic framework (MOF) composite (NiMo polyhedron) as an active electrocatalyst material for HER application - synthesized through the conventional hydrothermal process. The bimetallic MOF system having grown on Nickel foam (NiMo/[email protected]/NF) delivers higher catalytic activity by achieving a current density of 10 mA cm−2 at a low overpotential of 80 mV, with a Tafel slope of 98.9 mV dec−1 (0.5 M H2SO4), comparing favorably with the electrochemical enactment of existing bimetallic MOF-based catalysts. The enhanced HER activity of the synthesized MOF, is primarily due to the structural merits of MOF and the synergy between the MOF and the guest species (Ni and Mo metal atoms). Adding to the excellent HER performance, the electrode also exhibits good stability in acidic medium for a prolonged duration of 24 h. Hence, the synthesized low-cost, non-Pt electrode MOFs with its greater HER performance can be an auspicious applicant as an HER catalyst for water splitting and hydrogen generation applications.
K. Karuppasamy; Vasanth Rajendiran Jothi; Dhanasekaran Vikraman; K. Prasanna; Thandavarayan Maiyalagan; Byoung-In Sang; Sung-Chul Yi; Hyun-Seok Kim. Metal-organic framework derived NiMo polyhedron as an efficient hydrogen evolution reaction electrocatalyst. Applied Surface Science 2019, 478, 916 -923.
AMA StyleK. Karuppasamy, Vasanth Rajendiran Jothi, Dhanasekaran Vikraman, K. Prasanna, Thandavarayan Maiyalagan, Byoung-In Sang, Sung-Chul Yi, Hyun-Seok Kim. Metal-organic framework derived NiMo polyhedron as an efficient hydrogen evolution reaction electrocatalyst. Applied Surface Science. 2019; 478 ():916-923.
Chicago/Turabian StyleK. Karuppasamy; Vasanth Rajendiran Jothi; Dhanasekaran Vikraman; K. Prasanna; Thandavarayan Maiyalagan; Byoung-In Sang; Sung-Chul Yi; Hyun-Seok Kim. 2019. "Metal-organic framework derived NiMo polyhedron as an efficient hydrogen evolution reaction electrocatalyst." Applied Surface Science 478, no. : 916-923.