This page has only limited features, please log in for full access.
The alkaline fractionation of rice husk (RH) with NaOH was optimized for the purpose of obtaining a high-yield recovery of glucan and increasing the removal rate for lignin and ash, resulting in a hemicellulose-rich hydrolysate. The determined optimal conditions were a temperature of 150 °C, reaction time of 45 min, and NaOH concentration of 6% (w/v). The glucan content in the fractionated RH (Fr. RH) was 80.1%, which was significantly increased compared to the raw RH (35.6%). High glucan content in the fractionated solid residue is the most essential factor for minimizing enzyme dosages in enzymatic saccharification. The final enzymatic digestibilities (at 96 h) of raw and NaOH-Fr. RH with cellulase loadings of 30 FPU/g cellulose were 10.5% and 81.3%, respectively. Approximately 71.6% of the xmg content (mainly xylose) was concomitantly degraded into the fractionated hydrolysate (Fr. Hydrolysate). When this hydrolysate was acidified with sulfuric acid and subjected to heat treatment, a furfural production yield of about 64.9% was obtained. The results show that two-stage fed-batch fermentation with glucan-rich Fr. RH has the potential to achieve high-ethanol titers of 28.7 g/L.
Hyun Jin Jung; Kyeong Keun Oh. NaOH-Catalyzed Fractionation of Rice Husk Followed by Concomitant Production of Bioethanol and Furfural for Improving Profitability in Biorefinery. Applied Sciences 2021, 11, 7508 .
AMA StyleHyun Jin Jung, Kyeong Keun Oh. NaOH-Catalyzed Fractionation of Rice Husk Followed by Concomitant Production of Bioethanol and Furfural for Improving Profitability in Biorefinery. Applied Sciences. 2021; 11 (16):7508.
Chicago/Turabian StyleHyun Jin Jung; Kyeong Keun Oh. 2021. "NaOH-Catalyzed Fractionation of Rice Husk Followed by Concomitant Production of Bioethanol and Furfural for Improving Profitability in Biorefinery." Applied Sciences 11, no. 16: 7508.
Low-acid hydrothermal (LAH) fractionation conditions were optimized for the effective degradation of hemicellulose from pine wood (Pinus densiflora). The hemicellulosic sugar yield was maximized at 82.5% when the pine wood was fractionated at 190 °C, with 0.5 wt.% of sulfuric acid, and for 10 min. Consecutively, acidified heat treatment with zinc chloride and solvent extraction with ethyl acetate were carried out for the recovery of bio-based platform chemicals, such as furfural and acetic acid, from liquid hydrolysate through liquid–liquid extraction (LLE). Overall, 61.5% of xylose was decomposed into furfural, and the yield of acetic acid was 62.3% and furfural 66.1%. After LAH fractionation, 64.8% of the solid remained and was pelletized. The pellets showed excellent fuel characteristics, i.e., significant ash rejection (74.5%) and high calorific values (4770 kcal/kg), and the precursors of NOx and SOx also decreased by up to 60.0% and 71.4%, respectively.
Hyun Jin Jung; Kyeong Keun Oh. Production of Bio-Based Chemicals, Acetic Acid and Furfural, through Low-Acid Hydrothermal Fractionation of Pine Wood (Pinus densiflora) and Combustion Characteristics of the Residual Solid Fuel. Applied Sciences 2021, 11, 7435 .
AMA StyleHyun Jin Jung, Kyeong Keun Oh. Production of Bio-Based Chemicals, Acetic Acid and Furfural, through Low-Acid Hydrothermal Fractionation of Pine Wood (Pinus densiflora) and Combustion Characteristics of the Residual Solid Fuel. Applied Sciences. 2021; 11 (16):7435.
Chicago/Turabian StyleHyun Jin Jung; Kyeong Keun Oh. 2021. "Production of Bio-Based Chemicals, Acetic Acid and Furfural, through Low-Acid Hydrothermal Fractionation of Pine Wood (Pinus densiflora) and Combustion Characteristics of the Residual Solid Fuel." Applied Sciences 11, no. 16: 7435.
The parameters of the alkaline fractionation process were investigated and optimized using a statistical analysis method to simultaneously remove hemicellulose and ash from rice husk (RH) concomitantly. After the alkaline fractionation process, the residual solid contained high cellulose, and the recovery yield of hemicellulose was enhanced in the fractionated liquid hydrolyzate. The hemicellulosic sugar recovery yield (71.6%), de-ashing yield (>99%), and lignin removal (>80%) were obtained at the reaction conditions of 150 °C of temperature, 40 min of reaction time, and 6% (w/v) of NaOH concentration. Subsequently, nano-structured silica was synthesized using black liquor obtained as a by-product of this fractionation process. For the production of nano-structured silica, it was observed that the pH of a black liquor and the heat treatment temperature significantly influenced the textural properties of silica product. In addition, the two-stage bleaching of solid residue followed by colloid milling for the production of high value-added CNF with was attempted. As a result, in addition to 119 g of fermentable sugar, 143 g of high-purity (>98%) silica with a surface area of 328 m2g−1 and 273.1 g of high-functional CNF with cellulose content of 80.1% were simultaneously obtained from 1000 g of RH.
Hyun Jung; Hyun Kwak; Jinyoung Chun; Kyeong Oh. Alkaline Fractionation and Subsequent Production of Nano-Structured Silica and Cellulose Nano-Fibrils for the Comprehensive Utilization of Rice Husk. Sustainability 2021, 13, 1951 .
AMA StyleHyun Jung, Hyun Kwak, Jinyoung Chun, Kyeong Oh. Alkaline Fractionation and Subsequent Production of Nano-Structured Silica and Cellulose Nano-Fibrils for the Comprehensive Utilization of Rice Husk. Sustainability. 2021; 13 (4):1951.
Chicago/Turabian StyleHyun Jung; Hyun Kwak; Jinyoung Chun; Kyeong Oh. 2021. "Alkaline Fractionation and Subsequent Production of Nano-Structured Silica and Cellulose Nano-Fibrils for the Comprehensive Utilization of Rice Husk." Sustainability 13, no. 4: 1951.
The organosolv-fractionation process can act as a biorefinery process because it can separate the main components of biomass, such as lignin and hemicellulose, with high purity. The ethanol-based organosolv-fractionation process was applied to separate carbohydrates and lignin from rice husks, and the extraction behavior was observed according to various reaction variables. Various reaction conditions such as different temperatures (150 °C, 170 °C, and 190 °C), reaction times (30 min, 60 min, and 120 min), and ethanol concentrations (40%, 60%, and 80%) were tested while maintaining the solid:liquid ratio (1:10) and sulfuric acid concentration (0.25 wt.%). Two optimal reaction conditions for the target components were chosen: for sugar recovery, 150 °C, 60 min, and 40% ethanol were used as condition 1, and for lignin recovery, 170 °C, 120 min, and 80% ethanol were used as condition 2. Under condition 1, 91.5% of the glucan was preserved in the residual solid, and 75.0% of the xylan was extracted from the liquid hydrolysate. For condition 2, 59.9% of the lignin was recovered. To properly choose and apply the correct fractionation method and conditions, the reaction behavior (such as carbohydrate retention and extraction), lignin solubilization, and precipitation should be carefully considered.
Tae Kim; Hyun Kwak; Tae Kim; Kyeong Keun Oh. Reaction Characteristics of Organosolv-Fractionation Process for Selective Extraction of Carbohydrates and Lignin from Rice Husks. Energies 2021, 14, 686 .
AMA StyleTae Kim, Hyun Kwak, Tae Kim, Kyeong Keun Oh. Reaction Characteristics of Organosolv-Fractionation Process for Selective Extraction of Carbohydrates and Lignin from Rice Husks. Energies. 2021; 14 (3):686.
Chicago/Turabian StyleTae Kim; Hyun Kwak; Tae Kim; Kyeong Keun Oh. 2021. "Reaction Characteristics of Organosolv-Fractionation Process for Selective Extraction of Carbohydrates and Lignin from Rice Husks." Energies 14, no. 3: 686.
Ethanol organosolv fractionation combined with ball milling was conducted on three major agricultural residues: Rice husk (RH), rice straw (RS), and barley straw (BS). The highest lignin extraction yields of RH, RS, and BS were 55.2%, 53.1%, and 59.4% and the purity of lignin recovered was 99.5% for RH and RS, and 96.8% for BS, with similar chemical characteristics, i.e., low molecular weight distributions (1453–1817 g/mol) and poly dispersity index (1.15–1.28). However, considering the simultaneous production of hemicellulose-derived sugars, distinctive fractionation behaviors were shown for the three agricultural residues. The highest hemicellulose-derived sugar yield was 73.8% when RH was fractionated at 170 °C for 30 min. Meanwhile, very low sugar yields of 31.9% and 35.7% were obtained from RS and BS, respectively. The highest glucan-to-glucose conversion yield from enzymatic hydrolysis of fractionated RH reached 85.2%. Meanwhile, the enzymatic digestibility of the fractionated RS and BS was 60.0% and 70.5%, respectively. Consequently, the fractionation efficiency for RH can be improved with fine refinement. For the case of RS, other fractionation process should be applied to achieve effective fractionation performance.
Tae Hoon Kim; Hyun Kwak; Kyeong Keun Oh; Tae Kim; Tae Kim. Extraction Behaviors of Lignin and Hemicellulose-Derived Sugars During Organosolv Fractionation of Agricultural Residues Using a Bench-Scale Ball Milling Reactor. Energies 2020, 13, 352 .
AMA StyleTae Hoon Kim, Hyun Kwak, Kyeong Keun Oh, Tae Kim, Tae Kim. Extraction Behaviors of Lignin and Hemicellulose-Derived Sugars During Organosolv Fractionation of Agricultural Residues Using a Bench-Scale Ball Milling Reactor. Energies. 2020; 13 (2):352.
Chicago/Turabian StyleTae Hoon Kim; Hyun Kwak; Kyeong Keun Oh; Tae Kim; Tae Kim. 2020. "Extraction Behaviors of Lignin and Hemicellulose-Derived Sugars During Organosolv Fractionation of Agricultural Residues Using a Bench-Scale Ball Milling Reactor." Energies 13, no. 2: 352.
For the effective utilization of rice husk, organosolv fractionation was investigated to separate three main components (glucan, xylose, and lignin) with low acid concentration. Reaction temperatures of 170–190 °C, ethanol concentrations of 50%–70% (v/v), and sulfuric acid concentrations of 0%–0.7% (w/v) were investigated, with the reaction time and liquid-to-solid ratio kept constant at 60 min and 10, respectively. The fractionation conditions for the efficient separation into the three components of rice husk were determined to be 180 °C, 60% (v/v) of ethanol, and 0.25% (w/v) of sulfuric acid. Under these fractionation conditions, 86.8% of the xylan and 77.5% of the lignin were removed from the rice husk, and xylose and lignin were obtained from the liquid in 67.6% and 49.8% yields, respectively. The glucan digestibility of the fractionated rice husk was 85.2% with an enzyme loading of 15 FPU (filter paper unit) of cellulase per g-glucan.
Tae Hoon Kim; Hyun Jin Ryu; Kyeong Keun Oh. Improvement of Organosolv Fractionation Performance for Rice Husk through a Low Acid-Catalyzation. Energies 2019, 12, 1800 .
AMA StyleTae Hoon Kim, Hyun Jin Ryu, Kyeong Keun Oh. Improvement of Organosolv Fractionation Performance for Rice Husk through a Low Acid-Catalyzation. Energies. 2019; 12 (9):1800.
Chicago/Turabian StyleTae Hoon Kim; Hyun Jin Ryu; Kyeong Keun Oh. 2019. "Improvement of Organosolv Fractionation Performance for Rice Husk through a Low Acid-Catalyzation." Energies 12, no. 9: 1800.
The effect of organosolv pretreatment was investigated using a 30 L bench-scale ball mill reactor that was capable of simultaneously performing physical and chemical pretreatment. Various reaction conditions were tried in order to discover the optimal conditions for the minimal cellulose loss and enhanced enzymatic digestibility of Miscanthus × giganteus (MG), with conditions varying from room temperature to 170 °C for reaction temperature, from 30 to 120 min of reaction time, from 30% to 60% ethanol concentration, and a liquid/solid ratio (L/S) of 10–20 under non-catalyst conditions. The pretreatment effects were evaluated by chemical compositional analysis, enzymatic digestibility test and X-ray diffraction of the treated samples. The pretreatment conditions for the highest glucan digestibility yield were determined as 170 °C, reaction time of 90 min, ethanol concentration of 40% and L/S = 10. With these pretreatment conditions, the XMG (xylan + mannan + galactan) fractionation yield and delignification were 84.4% and 53.2%, respectively. The glucan digestibility of treated MG after the aforementioned pretreatment conditions was 86.0% with 15 filter paper units (FPU) of cellulase (Cellic® CTec2) per g-glucan enzyme loading.
Tae Hoon Kim; Dongjoong Im; Kyeong Keun Oh. Effects of Organosolv Pretreatment Using Temperature-Controlled Bench-Scale Ball Milling on Enzymatic Saccharification of Miscanthus × giganteus. Energies 2018, 11, 2657 .
AMA StyleTae Hoon Kim, Dongjoong Im, Kyeong Keun Oh. Effects of Organosolv Pretreatment Using Temperature-Controlled Bench-Scale Ball Milling on Enzymatic Saccharification of Miscanthus × giganteus. Energies. 2018; 11 (10):2657.
Chicago/Turabian StyleTae Hoon Kim; Dongjoong Im; Kyeong Keun Oh. 2018. "Effects of Organosolv Pretreatment Using Temperature-Controlled Bench-Scale Ball Milling on Enzymatic Saccharification of Miscanthus × giganteus." Energies 11, no. 10: 2657.
A combined ball milling and ethanol organosolv process is proposed for the pretreatment of three types of herbaceous biomass, giant miscanthus, corn stover, and wheat straw. The combined pretreatment was effective at both removing lignin and increasing the glucan content. After 120 min pretreatment, the glucan content increased to 63.09%, and 55.89% of the acid-insoluble lignin was removed from the giant miscanthus sample. The removal of cellulose, hemicellulose, and acetyl groups were correlated with the removal of lignin. The pretreatment of corn stover showed the highest removal of cellulose, but this was dependent on the removal of acid-insoluble lignin. The slope of the regression lines, which shows the correlation between the removal of lignin and cellulose, was lower than other correlations. The changes in biomass size were analyzed using size distribution graphs. With increasing pretreatment time, the particle size reduction improved in the three types of herbaceous biomass. Because of the combined physicochemical pretreatment, the enzymatic digestibility improved, and a maximum of 91% glucan digestibility was obtained from the pretreated corn stover when 30 FPU/g-glucan enzyme was added. Finally, compositional analysis of the recovered lignin from the remaining black liquor was investigated.
Seong Ju Kim; Byung Hwan Um; Dong Joong Im; Jin Hyung Lee; Kyeong Keun Oh. Combined Ball Milling and Ethanol Organosolv Pretreatment to Improve the Enzymatic Digestibility of Three Types of Herbaceous Biomass. Energies 2018, 11, 2457 .
AMA StyleSeong Ju Kim, Byung Hwan Um, Dong Joong Im, Jin Hyung Lee, Kyeong Keun Oh. Combined Ball Milling and Ethanol Organosolv Pretreatment to Improve the Enzymatic Digestibility of Three Types of Herbaceous Biomass. Energies. 2018; 11 (9):2457.
Chicago/Turabian StyleSeong Ju Kim; Byung Hwan Um; Dong Joong Im; Jin Hyung Lee; Kyeong Keun Oh. 2018. "Combined Ball Milling and Ethanol Organosolv Pretreatment to Improve the Enzymatic Digestibility of Three Types of Herbaceous Biomass." Energies 11, no. 9: 2457.
A two-stage method using gaseous ammonia and hot water was proposed to recover xylan and lignin from Miscanthus. In this method, Miscanthus was treated with gaseous ammonia at elevated temperatures (60–150°C) for various reaction times (1–48 h) in the first stage, termed as LMAA (low-moisture anhydrous ammonia) treatment. In the following stage, the LMAA-treated solid was subjected to hot-water treatment in a flow-through column reactor under various reaction conditions (170–220°C, 30–90 min). After two-stage processing, the remaining solid contained mostly glucan (∼80% cellulose), which became highly digestible by enzymes. The optimal treatment conditions for sugar recovery using two-stage process were 120°C and 12 h for the 1st stage and 190°C, 90 min, and 5 mL/min for the 2nd stage, which resulted in 84.2% xylan recovery in liquid phase and 95.3% glucan digestibility of the treated solid, using 15 FPU/g-glucan enzyme loading after the two-stage treatment.
Roent Dune A. Cayetano; Tae Hyun Kim. Two-stage processing of Miscanthus giganteus using anhydrous ammonia and hot water for effective xylan recovery and improved enzymatic saccharification. Bioresource Technology 2018, 255, 163 -170.
AMA StyleRoent Dune A. Cayetano, Tae Hyun Kim. Two-stage processing of Miscanthus giganteus using anhydrous ammonia and hot water for effective xylan recovery and improved enzymatic saccharification. Bioresource Technology. 2018; 255 ():163-170.
Chicago/Turabian StyleRoent Dune A. Cayetano; Tae Hyun Kim. 2018. "Two-stage processing of Miscanthus giganteus using anhydrous ammonia and hot water for effective xylan recovery and improved enzymatic saccharification." Bioresource Technology 255, no. : 163-170.
In order to produce bioethanol from yellow poplar sawdust without detoxification, deacetylation (mild alkali treatment) was performed with aqueous ammonia solution. To select the optimal conditions, deacetylation was carried out under different conditions: NH4OH loading (2–10% (w/v)) and a solid-to-liquid ratio of 1:4–1:10 at 121 °C for 60 min. In order to assess the effectiveness of deacetylation, fractionation of deacetylated yellow poplar sawdust was performed using dilute acid (H2SO4, 0.5–2.0% (w/v)) at a reaction temperature of 130–150 °C for 10–80 min. The toxicity-reduced hemicellulosic hydrolyzates that were obtained through a two-step treatment at optimized conditions were fermented using Pichia stipitis for ethanol production, without any further detoxification. The maximum ethanol production was 4.84 g/L, corresponding to a theoretical ethanol yield of 82.52%, which is comparable to those of intentionally made hydrolyzates as controls.
Seong Ju Kim; Tae Hyun Kim; Kyeong Keun Oh. Deacetylation Followed by Fractionation of Yellow Poplar Sawdust for the Production of Toxicity-Reduced Hemicellulosic Sugar for Ethanol Fermentation. Energies 2018, 11, 404 .
AMA StyleSeong Ju Kim, Tae Hyun Kim, Kyeong Keun Oh. Deacetylation Followed by Fractionation of Yellow Poplar Sawdust for the Production of Toxicity-Reduced Hemicellulosic Sugar for Ethanol Fermentation. Energies. 2018; 11 (2):404.
Chicago/Turabian StyleSeong Ju Kim; Tae Hyun Kim; Kyeong Keun Oh. 2018. "Deacetylation Followed by Fractionation of Yellow Poplar Sawdust for the Production of Toxicity-Reduced Hemicellulosic Sugar for Ethanol Fermentation." Energies 11, no. 2: 404.
Yellow poplar sawdust (YPS), a wood waste that can be easily collected from a local furniture factory, was fractionated using continuous twin screw-driven reactor for high hemicellulosic sugar recovery. The highest total sugar yields were attained under the following conditions: a barrel temperature of 127°C, sulfuric acid concentration of 0.8wt%, liquid feeding rate of 25mL/min, solid feeding rate of 2.0g/min, screw rotation speed of 25rpm, and residence time of 14.5min. The glucan and hemicellulose contents of the CTSR-fractionated YPS were 47.8% and 10.4%, respectively, and these results indicated that 44.9% of cellulose and 76.3% of the hemicellulose were extracted into liquid hydrolyzate. Meanwhile, the batch fractionation of YPS at the same reaction conditions showed a little fractionation effect, i.e., only 20.5% of hemicellulosic sugar yield was obtained.
Won Il Choi; Hyun Jin Ryu; Seong Ju Kim; Kyeong Keun Oh. Thermo-mechanical fractionation of yellow poplar sawdust with a low reaction severity using continuous twin screw-driven reactor for high hemicellulosic sugar recovery. Bioresource Technology 2017, 241, 63 -69.
AMA StyleWon Il Choi, Hyun Jin Ryu, Seong Ju Kim, Kyeong Keun Oh. Thermo-mechanical fractionation of yellow poplar sawdust with a low reaction severity using continuous twin screw-driven reactor for high hemicellulosic sugar recovery. Bioresource Technology. 2017; 241 ():63-69.
Chicago/Turabian StyleWon Il Choi; Hyun Jin Ryu; Seong Ju Kim; Kyeong Keun Oh. 2017. "Thermo-mechanical fractionation of yellow poplar sawdust with a low reaction severity using continuous twin screw-driven reactor for high hemicellulosic sugar recovery." Bioresource Technology 241, no. : 63-69.
A combined process, de-algination followed by enzymatic saccharification, was designed to produce alginate and glucose from Saccharina japonica consecutively. The process conditions of de-algination were optimized separately for each stage of acidification and alkaline extraction. Collectively, the de-algination yield was 70.1% under the following optimized conditions: 2.4 wt% of NaCO, 70 °C, and 100 min with the acidified S. japonica immersed in a 0.5 wt% HSO solution for 2 h at room temperature. The glucan content in the de-alginated S. japonica increased to 38.0%, which was approximately fivefold higher than that of the raw S. japonica. The enzymatic hydrolysis of the de-alginated S. japonica almost completed in 9 h, affording 5.2 g (96.8% of glucan digestibility) of glucose at a de-alginated S. japonica loading of 14.2 g.
Hyun Jin Ryu; Kyeong Keun Oh. Combined De-Algination Process as a Fractionation Strategy for Valorization of Brown Macroalga Saccharina japonica. Applied Biochemistry and Biotechnology 2016, 182, 238 -249.
AMA StyleHyun Jin Ryu, Kyeong Keun Oh. Combined De-Algination Process as a Fractionation Strategy for Valorization of Brown Macroalga Saccharina japonica. Applied Biochemistry and Biotechnology. 2016; 182 (1):238-249.
Chicago/Turabian StyleHyun Jin Ryu; Kyeong Keun Oh. 2016. "Combined De-Algination Process as a Fractionation Strategy for Valorization of Brown Macroalga Saccharina japonica." Applied Biochemistry and Biotechnology 182, no. 1: 238-249.
Low acid hydrothermal (LAH) fractionation was developed for the effective recovery of hemicellulosic sugar (mainly xylose) from Miscanthus sacchariflorus Goedae-Uksae 1 (M. GU-1). The xylose yield was maximized at 74.75% when the M. GU-1 was fractionated at 180°C and 0.3wt.% of sulfuric acid for 10min. At this condition, the hemicellulose (mainly xylan) degradation was 86.41%. The difference between xylan degradation and xylose recovery yield, i.e., xylan loss, was 11.66%, as indicated by the formation of decomposed products. The furfural, the value added biochemical product, was also obtained by 0.42g/L at this condition, which was 53.82% of furfural production yield based on the xylan loss. After then, the furfural production continued to increase to a maximum concentration of 1.87g/L, at which point the xylan loss corresponded to 25.87%.
Tae Hyun Kim; Hyun Jin Ryu; Kyeong Keun Oh. Low acid hydrothermal fractionation of Giant Miscanthus for production of xylose-rich hydrolysate and furfural. Bioresource Technology 2016, 218, 367 -372.
AMA StyleTae Hyun Kim, Hyun Jin Ryu, Kyeong Keun Oh. Low acid hydrothermal fractionation of Giant Miscanthus for production of xylose-rich hydrolysate and furfural. Bioresource Technology. 2016; 218 ():367-372.
Chicago/Turabian StyleTae Hyun Kim; Hyun Jin Ryu; Kyeong Keun Oh. 2016. "Low acid hydrothermal fractionation of Giant Miscanthus for production of xylose-rich hydrolysate and furfural." Bioresource Technology 218, no. : 367-372.
Fractionation of EFB was conducted in two consecutive steps using a batch reaction system: hemicellulose hydrolysis using acetic acid (AA; 3.0–7.0 wt.%) at 170–190 °C for 10–20 min in the first stage, and lignin solubilization using ammonium hydroxide (5–20 wt.%) at 140–220 °C for 5–25 min in the second stage. The two-stage process effectively fractionated empty fruit bunches (EFB) in terms of hemicellulose hydrolysis (53.6%) and lignin removal (59.5%). After the two-stage treatment, the fractionated solid contained 65.3% glucan. Among three investigated process parameters, reaction temperature and ammonia concentration had greater impact on the delignification reaction in the second stage than reaction time. The two-stage fractionation processing improved the enzymatic digestibility to 72.9% with 15 FPU of cellulase/g of glucan supplemented with 70 pNPG of β-glycosidase (Novozyme 188)/g-glucan, which was significantly enhanced from the equivalent digestibility of 28.3% for untreated EFB and 45.7% for AAH-fractionated solid.
Dong Young Kim; Young Soo Kim; Tae Hyun Kim; Kyeong Keun Oh. Two-stage, acetic acid-aqueous ammonia, fractionation of empty fruit bunches for increased lignocellulosic biomass utilization. Bioresource Technology 2016, 199, 121 -127.
AMA StyleDong Young Kim, Young Soo Kim, Tae Hyun Kim, Kyeong Keun Oh. Two-stage, acetic acid-aqueous ammonia, fractionation of empty fruit bunches for increased lignocellulosic biomass utilization. Bioresource Technology. 2016; 199 ():121-127.
Chicago/Turabian StyleDong Young Kim; Young Soo Kim; Tae Hyun Kim; Kyeong Keun Oh. 2016. "Two-stage, acetic acid-aqueous ammonia, fractionation of empty fruit bunches for increased lignocellulosic biomass utilization." Bioresource Technology 199, no. : 121-127.
Physicochemical characteristics of corn stover pretreated by soaking in aqueous ammonia (SAA) and low-moisture anhydrous ammonia (LMAA) were compared and investigated. The glucan digestibility of the treated biomass reached 90 % (SAA) and 84 % (LMAA). The LMAA pretreatment enhanced the digestibility by cleaving cross-linkages between cell wall components, whereas the SAA pretreatment additionally improved the digestibility by efficiently removing a major portion of the lignin under mild reaction conditions without significant loss of carbohydrates. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC) revealed the structural and chemical transformations of lignin during the pretreatments. Both pretreatments effectively cleaved ferulate cell wall cross-linking that is associated with the recalcitrance of grass lignocellulosics toward enzymatic saccharification. Extracted lignin from SAA pretreatment was extensively depolymerized but retained “native” character, as evidenced by the retention of β-ether linkages.
Chang Geun Yoo; Hoon Kim; Fachuang Lu; Ali Azarpira; Xuejun Pan; Kyeong Keun Oh; Jun Seok Kim; John Ralph; Tae Hyun Kim. Understanding the Physicochemical Characteristics and the Improved Enzymatic Saccharification of Corn Stover Pretreated with Aqueous and Gaseous Ammonia. BioEnergy Research 2015, 9, 67 -76.
AMA StyleChang Geun Yoo, Hoon Kim, Fachuang Lu, Ali Azarpira, Xuejun Pan, Kyeong Keun Oh, Jun Seok Kim, John Ralph, Tae Hyun Kim. Understanding the Physicochemical Characteristics and the Improved Enzymatic Saccharification of Corn Stover Pretreated with Aqueous and Gaseous Ammonia. BioEnergy Research. 2015; 9 (1):67-76.
Chicago/Turabian StyleChang Geun Yoo; Hoon Kim; Fachuang Lu; Ali Azarpira; Xuejun Pan; Kyeong Keun Oh; Jun Seok Kim; John Ralph; Tae Hyun Kim. 2015. "Understanding the Physicochemical Characteristics and the Improved Enzymatic Saccharification of Corn Stover Pretreated with Aqueous and Gaseous Ammonia." BioEnergy Research 9, no. 1: 67-76.
Xylose, mannose, and galactose (xmg) recovery from empty fruit bunches using acetic acid-assisted hydrothermal (AAH) fractionation method was investigated. Acetic acid has been demonstrated to be effective in xmg recovery in comparison with the liquid hot-water (LHW) fractionation. The maximum xmg recovery yield (50.7 %) from the empty fruit bunch (EFB) was obtained using AAH fractionation at optimum conditions (6.9 wt.% acetic acid at 170 °C and for 18 min); whereas, only 16.2 % of xmg recovery was obtained from the LHW fractionation at the same reaction conditions (170 °C and 18 min). Releasing out the glucose from EFB was kept at low level (
Ng Young Kim; Byung Hwan Um; Kyeong Keun Oh. Acetic acid-assisted hydrothermal fractionation of empty fruit bunches for high hemicellulosic sugar recovery with low byproducts. Applied Biochemistry and Biotechnology 2015, 176, 1445 -1458.
AMA StyleNg Young Kim, Byung Hwan Um, Kyeong Keun Oh. Acetic acid-assisted hydrothermal fractionation of empty fruit bunches for high hemicellulosic sugar recovery with low byproducts. Applied Biochemistry and Biotechnology. 2015; 176 (5):1445-1458.
Chicago/Turabian StyleNg Young Kim; Byung Hwan Um; Kyeong Keun Oh. 2015. "Acetic acid-assisted hydrothermal fractionation of empty fruit bunches for high hemicellulosic sugar recovery with low byproducts." Applied Biochemistry and Biotechnology 176, no. 5: 1445-1458.
Tae Hyun Kim; Kyeong Keun Oh; Hyun Jin Ryu; Kyong-Hwan Lee. Hydrolysis of hemicellulose from barley straw and enhanced enzymatic saccharification of cellulose using acidified zinc chloride. Renewable Energy 2014, 65, 56 -63.
AMA StyleTae Hyun Kim, Kyeong Keun Oh, Hyun Jin Ryu, Kyong-Hwan Lee. Hydrolysis of hemicellulose from barley straw and enhanced enzymatic saccharification of cellulose using acidified zinc chloride. Renewable Energy. 2014; 65 ():56-63.
Chicago/Turabian StyleTae Hyun Kim; Kyeong Keun Oh; Hyun Jin Ryu; Kyong-Hwan Lee. 2014. "Hydrolysis of hemicellulose from barley straw and enhanced enzymatic saccharification of cellulose using acidified zinc chloride." Renewable Energy 65, no. : 56-63.
A new analysis method for alginate quantification in the brown alga, Saccharina japonica, was developed and evaluated. In this method, (1) alginate was treated with Na2CO3; (2) the alginate-derived compound in the hydrolysate was analyzed using high-performance liquid chromatography (HPLC); and then, (3) one of the HPLC peaks was selected and used to establish the standard calibration curve to estimate the intact alginate content in the raw material. The results obtained using the new method were verified by the Kennedy and Bradshaw method, which confirmed that the new method can be an effective method for the estimation of the alginate content in S. japonica. An experimental equation was developed to estimate the alginic acid concentration in the hydrolysate obtained from Na2CO3 treatment of the model compound (Sigma Na-alginate) at various reaction conditions on the basis of the correlation between estimated alginic acid contents and combined severity factors (CSF). The statistical analysis confirmed that the equation gave consistent results, i.e., approximately 81 % of the test groups lie within
Tae Hyun Kim; Won Il Choi; Young Soo Kim; Kyeong Keun Oh. A novel alginate quantification method using high-performance liquid chromatography (HPLC) for pretreatment of Saccharina japonica. Environmental Biology of Fishes 2014, 27, 511 -518.
AMA StyleTae Hyun Kim, Won Il Choi, Young Soo Kim, Kyeong Keun Oh. A novel alginate quantification method using high-performance liquid chromatography (HPLC) for pretreatment of Saccharina japonica. Environmental Biology of Fishes. 2014; 27 (1):511-518.
Chicago/Turabian StyleTae Hyun Kim; Won Il Choi; Young Soo Kim; Kyeong Keun Oh. 2014. "A novel alginate quantification method using high-performance liquid chromatography (HPLC) for pretreatment of Saccharina japonica." Environmental Biology of Fishes 27, no. 1: 511-518.
Fractionation and delignification of empty fruit bunches (EFB) was conducted in a series of two steps under low reaction severity with the aim of minimizing the neutralization of hydrolyzates. In EFB underwent acid fractionation, the glucan content was increased to 62.4%, at which point 86.9% of the hemicellulosic sugar and 20.5% of the lignin were extracted from the raw EFB. Xylose-rich hydrolyzate, indicating a high selectivity of 17.7 could be separated. Through the consecutive delignification of acid-fractionated EFB using sodium hydroxide, solid residue with a high glucan content (70.4%) and low hemicellulosic sugar content (3.7%) could be obtained, which indicated that 95.9% of the hemicellulosic sugar and 67.5% of the lignin were extracted based on raw EFB. The final pretreated solid residue was converted to glucose through enzyme hydrolysis, which resulted in an enzymatic digestibility of 76.9% was achieved.
Jin Young Hong; Young Soo Kim; Kyeong Keun Oh. Fractionation and delignification of empty fruit bunches with low reaction severity for high sugar recovery. Bioresource Technology 2013, 146, 176 -183.
AMA StyleJin Young Hong, Young Soo Kim, Kyeong Keun Oh. Fractionation and delignification of empty fruit bunches with low reaction severity for high sugar recovery. Bioresource Technology. 2013; 146 ():176-183.
Chicago/Turabian StyleJin Young Hong; Young Soo Kim; Kyeong Keun Oh. 2013. "Fractionation and delignification of empty fruit bunches with low reaction severity for high sugar recovery." Bioresource Technology 146, no. : 176-183.
Since extrusion has many desirable characteristics such as high shear, rapid mixing, short residence time, controllable barrel temperature, and adaptability to process modification, the technology has been applied as a viable continuous pretreatment method for empty fruit bunches (EFB).
Won-Il Choi; Kyeong-Keun Oh; Ji-Yeon Park; Jin-Suk Lee. Continuous sodium hydroxide-catalyzed pretreatment of empty fruit bunches (EFB) by continuous twin-screw-driven reactor (CTSR). Journal of Chemical Technology & Biotechnology 2013, 89, 290 -296.
AMA StyleWon-Il Choi, Kyeong-Keun Oh, Ji-Yeon Park, Jin-Suk Lee. Continuous sodium hydroxide-catalyzed pretreatment of empty fruit bunches (EFB) by continuous twin-screw-driven reactor (CTSR). Journal of Chemical Technology & Biotechnology. 2013; 89 (2):290-296.
Chicago/Turabian StyleWon-Il Choi; Kyeong-Keun Oh; Ji-Yeon Park; Jin-Suk Lee. 2013. "Continuous sodium hydroxide-catalyzed pretreatment of empty fruit bunches (EFB) by continuous twin-screw-driven reactor (CTSR)." Journal of Chemical Technology & Biotechnology 89, no. 2: 290-296.