• Journal of the Korean Wood Science and Technology
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• v.50 no.3
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• pp.149-158
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• 2022

To realize the infinite possibilities of materials derived from wood, it is necessary to overcome the weak moisture stability of wood. Thus, the development of an eco-friendly hydrophobic coating agent is essential, and of these, woody biomass-based materials are strongly attractive as coatings. In this study, eco-friendly hydrophobic wood coatings were prepared using carnauba wax purified from palm leaves and sprouts, and kraft lignin. The physicochemical properties of the carnauba wax/lignin blends according to the ratio of carnauba wax and lignin were observed by morphology and functional group change. In addition, the coating performance of carnauba wax/lignin blend coatings was confirmed by measuring the contact angle change. It was found that the addition of lignin could accelerate the atomization of wax particles, and that micro-roughness can be realized when applied to the actual wood surface, to ensure that the coating effect over time lasts longer. In addition, it was confirmed that the addition of lignin increases the hydrogen-bond-based interaction with the wood of the coating, thereby providing better coating stability and increasing the durability of the coating solvent under friction. The carnauba wax/lignin paint developed in this way is eco-friendly because all components are made of wood-based raw materials and have an excellent affinity with wood surfaces. Therefore, it is expected to be applicable to the coating process of wood-plastic composites and timber composites.

• Clean Technology
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• v.23 no.2
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• pp.121-132
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• 2017

The increase of greenhouse gases and the concern of global warming instigate the development and spread of renewable energy and hydrogen is considered one of the clean energy sources. Hydrogen is one of the most elements in the earth and exist in the form of fossil fuel, biomass and water. In order to use hydrogen for a clean energy source, the hydrogen production method should be eco-friendly and economic as well. There are two different hydrogen production methods: conventional thermal method using fossil fuel and renewable method using biomass and water. Steam reforming, autothermal reforming, partial oxidation, and gasification (using solid fuel) have been considered for hydrogen production from fossil fuel. When using fossil fuel, carbon dioxide should be separated from hydrogen and captured to be accepted as a clean energy. The amount of hydrogen from biomass is insignificant. In order to occupy noticeable portion in hydrogen industries, biomass conversion, especially, biological method should be sufficiently improved in a process efficiency and a microorganism cultivation. Electrolysis is a mature technology and hydrogen from water is considered the most eco-friendly method in terms of clean energy when the electric power is from renewable sources such as photovoltaic cell, solar heat, and wind power etc.

• Textile Coloration and Finishing
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• v.30 no.2
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• pp.141-149
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• 2018

This study aimed to investigate the efficacy of eco-friendly leather dyeing by utilizing food wastes. Natural dyeing of eel skin was attempted using onion peels which have been used commonly for natural dyeing of textile fabrics. Eel skin is a by-product from fishery processing and is used mainly for making leather products. The colorant was extracted from onion peels in boiling water, concentrated, and freeze-dried. Dyeing of eel skin was carried out to study the effects of dyeing conditions, mordant type and mordanting method on dye uptake, color change, drape stiffness and colorfastness. The optimum dyeing conditions were $60^{\circ}C$ of dyeing temperature, 60min of dyeing time at 1:100($H_2O$ 90%: ethanol 10%) of bath ratio. The onion peels produced yellowish color on eel skin. The pre-mordanting was effective than the post-mordanting. As a result of the drape stiffness measurement, the Fe-mordanted sample was somewhat stiffer comparing to other mordanted samples. The light fastness of the non-mordant dye was excellent in 3-4 grade. Drycleaning fastness and rubbing fastness showed excellent results, but fastness was not significantly improved by mordanting.

• Elastomers and Composites
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• v.52 no.4
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• pp.249-256
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• 2017

The history of polyurethane is relatively shorter compared to that of the other polymers, though its importance has grown rapidly. Due to its unique properties, polyurethanes are widely applied in various fields. In particular, the automotive industry is one of the important application fields. To date, polyols and isocyanates used in the polyurethane industry are generally of petrochemical origin. Recently, owing to the oil crisis, legislation, and growing awareness towards environmental preservation, the demand for more sustainable and eco-friendly raw materials has increased. In this paper, the latest research and development trends in polyurethane applications were reviewed, with a focus on the automobile industry in areas such as seat comfort, noise reduction, light weight, biomass-based polyurethane, and recycling.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.243-249
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• 2011

In the world, burning fossil fuels such as oil, petroleum, gasoline has created the global warming due to especially carbon dioxide gas emission. Therefore, these fossil fuels must be replaced by eco-friendly feadstocks. The wood pellets are one of valuable alternative fuels that can replace oil-based fuels within a short period of time. Unfortunately, there are no enough forest biomass for wood pellets in Korea. Nevertheless, Korea government has been trying to use most of forest biomass generated from the National Forest Management Operation. This does not make sense in an economic point of view.

• Applied Chemistry for Engineering
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• v.19 no.2
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• pp.137-144
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• 2008

In these days, there has been increased focus on global warming and the exhaustion of resources caused by the heavy consumption of fossil resources. In order to resolve these problems, biomass is increasingly gaining international attention as a source of renewable energy. Biodiesel fuel produced by the transesterification of vegetable oils and animal fats is expected to be one of the eco-friendly biomass based alternatives to petrodiesel. This article reviews some of the research for effective of biodiesel production.

• 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.

• The Journal of Korean Institute for Practical Engineering Education
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• v.3 no.1
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• pp.183-192
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• 2011

In recent years there has been an increasing focus on global warming and the exhaustion of resources caused by the heavy consumption of fossil fuels. In order to resolve these issues, biomass has gained much attention as a source of renewable energy. One area of particular interest has been the production of biodiesel. The biodiesel produced by the transesterification of vegetable oils, animal fats and waste cooking oils is expected to be one of the eco-friendly biomass-based alternatives to fossil fuels. This paper reviews some of the recent findings for the effective biodiesel production system, together with several factors affecting the biodiesel yield.

• Journal of Biosystems Engineering
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• v.38 no.3
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• pp.180-184
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• 2013

Purpose: This study explored the factors influencing heating value in the process of torrefaction of water hyacinth. Methods: Torrefaction was applied with three temperature settings (200, 300, $400^{\circ}C$) and three time settings (1, 2, 3 h) using small electric heaters (11.3L of holding volume). This study investigated the heating values with the washing process and process factors influenced the torrefaction. In addition, this study compared the heating values in washed and unwashed samples and suggested the optimal conditions for increasing heating value. Results: Torrefaction increased the heating value by 8.18 ~ 30.04%. Comparing heating values of each condition, the optimal temperature for torrefaction was $300^{\circ}C$ and holding time was 1 hour. The washing process increased the heating value by 19 ~ 27%. The heating value of the sample treated at $300^{\circ}C$ for three hours was 4310.80 kcal/kg, which was greater than the first class wood pellet of 4300 kcal/kg. Conclusions: This study proved that the torrefaction and washing process increased the heating value of water hyacinth. Therefore, water hyacinth is expected to be an eco-friendly biomass which substitutes for wood pellet.

• Journal of Ocean Engineering and Technology
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• v.27 no.6
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• pp.7-15
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• 2013

Eco-friendly and sustainable seaweed biomass energy have been under the spotlight as the future of renewable energy. However, seaweed culture is primarily conducted inshore, with the research on offshore culture still in an early stage. For massive biomass production, a systematic engineering approach is required to devise offshore seaweed culture facilities rather than the conventional empirical ones. To establish the fundamental behavior of seaweed culture facilities, the dynamic characteristics of a seaweed culture facility were analyzed in the study. For this purpose, numerical analyses of the seaweed culture facility (a frame type) were carried out by using the hydrodynamic simulation program ANSYS-AQWA. For the analysis, environmental loads were considered using the wave spectra and co-linear current; mooring variables were selected as parameters; and time domain analyses were carried out to acquire the time series responses and eventually the dynamic characteristics. Finally, the mooring performance was evaluated. It was found that the motion could be controlled by adjusting the buoyancy and mooring slope.