• Elastomers and Composites
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• v.46 no.3
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• pp.195-203
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• 2011

Eco-friendly materials or bio-composites were made with poly(lactic acid) (PLA) as matrix polymer and kenaf fibers as filler. Also, acetylated kenaf fibers and compatibilizer were adopted in order to improve the interfacial adhesion between fiber and polymer. In this study, the effect of chemical modification and compatibilizer on the mechanical-viscoelastic and morphology properties of the bio-composites was discussed. The hydrophobic fibers by acetylation were known to show better interfacial bonding with the matrix polymer and resulted in improved performance and morphology. Viscoelastic property and glass transition temperature, however, were not nearly enhanced.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.209-210
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• 2019

Current international concerns are the energy crisis due to climate change and depletion of fossil fuels due to global warming. Korea has a very high dependency on energy imports 93%. In Korea, 63% of the country is forested, and a power plant using wood biomass is being built in Korea. Biomass fly ash, a by-product of biomass energy generation, is now being discarded. There is little research to utilize discarded biomass fly ash. Therefore, this study aims to solve the environmental problems, develop new mixed materials, improve the quality and utilize the biomass fly ash, which is a by-product of the industrial waste. As a result of the experiment, the flowability decreased as the replacement ratio of biomass fly ash increased. As the replacement ratio of biomass fly ash decreased, the amount of air content.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.1
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• pp.24-34
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• 2015

Domestic companies supplying electricity must increase obligatory duty to use renewable energy annually. If not met with obligatory allotment, the electricity-supply companies must pay RPS (Renewable Portfolio Standards) penalty. Although the power plants using a pulverizing coal firing boiler could co-fire up to around 3 per cent with wood pellets mixed in with coal feedstock without any major equipment revamps, they recorded only about 60 per cent fulfillment of RPS. Consequently, USD 46 million of RPS penalty was imposed on the six power supplying subsidiaries of GENCOs in 2014. One of the solutions to reduce the RPS penalty is that the power supply companies adopt the co-firing of torrefied lignocellulosic biomass in coal plants, which may contribute to the use of over 30 per cent of torrefied biomass mixed with bituminous coals. Extra binder was required to form pellets using torrefied biomass such as wood chips, PKS (Palm Kernel Shell) and EFB (Empty Fruit Bunch). Instead of corn starch, 30, 50 and 70 per cent of Larix saw dusts were respectively added to the torrefied feedstocks such as Pinus densiflora chips, PKS and EFB. The addition of saw dusts led to the decrease of the calorific values of the pellets but the forming ability of the pelletizer was exceedingly improved. Another advantage from the addition of saw dusts stemmed from the reduction of ash contents of the pellets. Finally, it was confirmed that torrefied oil palm biomass such as PKS and EFB could be valuable feedstocks in making pellets through improved binding ability.

• Resources Recycling
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• v.30 no.4
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• pp.46-53
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• 2021

Biomass can be considered as chemical energy obtained from nature, and includes all living organisms such as plants, animals, and microorganisms. Biomass is eco-friendly, is easily obtainable from the environment, and can be recycled without special treatment processes. Biomass can also be converted into bioenergy fuel through pyrolysis and fermentation. Therefore, it has been considered as a renewable energy source, which prevents the depletion of natural resources such as fossil fuels. In this study, torrefaction to increase the carbon content in various types of biomass sources (sawdust, rice straw, rice bristles, coffee ground, and waste wood) was conducted under an inert atmosphere and at a temperature of 523~573K. The possibility of using torrefied biomass as an alternative to solid fuel for industrial purposes was analyzed by examining the carbon concentration and combustion behaviors.

• Journal of the Korean Wood Science and Technology
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• v.44 no.2
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• pp.241-252
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• 2016

Cellulose acetate is one of well-known industrial materials which have various commercial uses. We treated the lignocellulosic biomass using two-step (steam explosion-chemical) reaction followed by acetylation to get the cellulose acetate in this study. The two-step treatment was done to improve the yields of acetylation of the substrates. The yields of the cellulose acetate were about 88.4, 88.1, and 151.7% in barley straw, rice straw, and oak tree, respectively. Also the degree of substitution (DS) of the acetates was 2.1 to 2.5 in the biomass. We found that the biomass were valuable cellulosic sources, including their derivatives, in this study. This means that the biomass can be converted into the high-valued cellulosic stuff.

• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1260-1268
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• 2013

A series of experiments were carried out with three native strains of microalgae to measure growth rates, biomass, and lipid productivities. Scenedesmus sp. IMMTCC-6 had better biomass growth rate and higher lipid production. The growth, lipid accumulation, and carbon dioxide ($CO_2$) consumption rate of Scenedesmus sp. IMMTCC-6 were tested under different NaOH concentrations in modified BBM. The algal strain showed the maximum specific growth rate (0.474/day), biomass productivity (110.9 mg $l^{-1}d^{-1}$), and $CO_2$ consumption rate (208.4 mg $l^{-1}d^{-1}$) with an NaOH concentration of 0.005 M on the $8^{th}$ day of cultivation. These values were 2.03-, 6.89-, and 6.88-fold more than the algal cultures grown in control conditions (having no NaOH and $CO_2$). The $CO_2$ fixing efficiency of the microalga with other alternative carbon sources like $Na_2CO_3$ and $NaHCO_3$ was also investigated and compared. The optimized experimental parameters at shake-flask scale were implemented for scaling up the process in a self-engineered photobioreactor. A significant increase in lipid accumulation (14.23% to 31.74%) by the algal strain from the logarithmic to stationary phases was obtained. The algal lipids were mainly composed of $C_{16}/C_{18}$ fatty acids, and are desirable for biodiesel production. The study suggests that microalga Scenedesmus sp. IMMTCC-6 is an efficient strain for biodiesel production and $CO_2$ biofixation using stripping solution of NaOH in a cyclic process.

• Journal of Forest and Environmental Science
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• v.26 no.2
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• pp.137-148
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• 2010

The high costs for ethanol production with lignocellulosic biomass as a second generation energy materials currently deter commercialization of lignocellulosic biomass, especially wood biomass which is considered as the most recalcitrant material for enzymatic hydrolysis mainly due to the high lignified structure and the nature of the lignin component. Therefore, overcoming recalcitrance of lignocellulosic biomass for converting carbohydrates into sugar that can subsequently be converted into biobased fuels and biobased products is the primary technical and economic challenge for bioconversion process. This study was mainly reviewed on the research trend of the enhancement of enzymatic hydrolysis for lignocellulosic biomass after pretreatment in bioethanol production process.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.1
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• pp.18-28
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• 2014

Renewable Portfolio Standards(RPS) is a regulation that requires a renewable energy generated from eco-friendly energy sources such as biomass, wind, solar, and geothermal. The RPS mechanism generally is an obligatory policy that places on electricity supply companies to produce a designated fraction of their electricity from renewable energies. The domestic companies to supply electricity largely rely on wood pellets in order to implement the RPS in spite of undesirable situation of lack of wood resources in Korea. This means that the electricity supply companies in Korea must explore new biomass as an alternative to wood. Palm kernel shell (PKS) and empty fruit bunch (EFB) as oil palm wastes can be used as raw materials used for making pellets after their thermochemical treatment like torrefaction. Torrefaction is a pretreatment process which serves to improve the properties including heating value and energy densification of these oil palm wastes through a mild pyrolysis at temperature typically ranging between 200 and $300^{\circ}C$ in the absence of oxygen under atmospheric pressure. Torrefaction of oil palms wastes at above $200^{\circ}C$ contributed to the increase of fixed carbon with the decrease of volatile matters, leading to the improvement of their calorific values over 20.9 MJ/kg (=5,000 kcal/kg) up to 25.1 MJ/kg (=6,000 kcal/kg). In particular, EFB sensitively responded to torrefaction because of its physical properties like fiber bundles, compared to PKS and hardwood chips. In conclusion, torrefaction treatment of PKS and EFB can greatly contribute to the implement of RPS of the electricity supply companies in Korea through the increased co-firing biomass with coal.

• Polymer(Korea)
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• v.38 no.4
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• pp.464-470
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• 2014

A chemo-mechanical method was used to prepare lignin-containing cellulose nanofibrils(L-CNF) from unbleached woodpulps dispersed uniformly in an organic solvent. L-CNF/PLA composites were obtained by solvent casting method. The effects of L-CNF concentration on the composite performances were characterized by tensile test machine, contact angle machine, scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR). The tensile test results indicated that the tensile strength and elongation-at-break increased by 50.6% and 31.8% compared with pure PLA. The contact angle of PLA composites decreased from $79.3^{\circ}$ to $68.9^{\circ}$. The FTIR analysis successfully showed that L-CNF had formed intermolecular hydrogen bonding with PLA matrix.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.5
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• pp.61-67
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• 2015

As the production of palm oil has been increased, the generation of oil palm biomass is also increased and the utilization of the oil palm biomass become more significant topic. One third of the oil palm biomass is empty fruit bunch (EFB) and the other two thirds are oil palm trunks and fronds. However, the effective use of oil palm biomass has not been developed and most of it is discarded near oil palm plants. In this study, we investigated the applicability of EFB to the paperboard mills, as an organic filler. The new organic filler was manufactured in a laboratory by grinding and fractionating dried EFB powder, and its properties were analyzed. The particles of EFB organic filler were larger and more spherical than those of the commercial wood powder. The use of EFB organic filler resulted in a higher bulk of the handsheets with similar trends of physical strength, compared to those made with wood powder. It was concluded that EFB could be used as a raw material to manufacture organic filler for paperboard production.