• 에너지공학
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• 제11권1호
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• pp.34-46
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• 2002

Carbon accounting is a key issue in the discussions on global warming/CO$_2$mitigation. This paper applies both the IPCC Approach and the NEAT (Non-Energy use Emission Accounting Tables) model, a bottom-up approach, to estimate the potential CO$_2$ emissions (carbon storage) originating from the non-energy use as to assess the actual CO$_2$ emissions (carbon release) from the use of fossil fuels in Korea. The current Korean carbon accounting seems to overestimate the potential CO$_2$ emissions and with it to underestimate the actual CO$_2$ emissions. The estimation shows that the potential CO$_2$ emissions calculated according to the IPCC Approach are lower than those calculated using the NEAT model. This is because the IPCC default storage fraction for naphtha seems to be low for the Korean petrochemical production structure, on the one hand and because the IPCC Approach does not consider the trade with short life petrochemical products, on the other hand. This paper shows that a bottom-up approach like the NEAT model can contribute to overcome some of limitations of the IPCC guidelines, especially by considering the international trade with short life petrochemical products and by estimating the storage fractions of fossil fuels used as feedstocks for the country in consideration. This paper emphasizes the importance of accurate energy statistics for carbon accounting.

• 한국수소및신에너지학회논문집
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• 제17권3호
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• pp.317-323
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• 2006

Electric conductive material should be homogeneously mixed with sulfur in sulfur electrode fabrication of lithium/sulfur battery, because sulfur is electric insulator. In this paper electrochemical properties of Li/S battery was studied with various compositions of sulfur electrodes. When content of sulfur changed from 40 wt.% to 80 wt.%, the 60 wt.% sulfur electrode showed the maximum capacity of 1489 mAh/g-sulfur. Electrochemical properties of Li/S battery using 60 wt.% sulfur was also investigated with various carbon contents. The discharge capacity changed as a function of carbon contents. The optimum composition was 25 wt.% carbon for 60 wt.% sulfur electrode.

• 한국산업보건학회지
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• 제24권3호
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• pp.353-358
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• 2014

Purpose: This study was conducted to evaluate desorption efficiency and storage stability on activated carbon acquired form domestic market. Materials: Mixture of acetone, benzene, normal hexane and toluene was injected on four types of charcoal 100 mg. After overnight, charcoal was desorbed by carbon disulfide $1m{\ell}$ and analyzed by gas chromatography with flame ionization detector. Results: Desorption efficiency of benzene, normal hexane and toluene in charcoal tubes were 95% ~ 105%. But desorption efficiency of acetone in charcoal tubes was below 75% and different from types of charcoal. The more injected amount of acetone on charcoal showed higher desorption efficiency. Acetone injected on charcoal tubes migrated from front section into back section after 10 days storage at room temperature. Conclusions: Desorption efficiency and storage stability of activated carbon acquired from domestic market was good for benzene, normal hexane and toluene. The activated carbon acquired from domestic market has ability to be used as sampling media.

• 공업화학
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• 제28권1호
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• pp.8-16
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• 2017

에너지 저장 및 환경 관련 분야에 응용 흡착매질로 바이오매스 기반 활성탄의 중요성을 살펴보았다. 지금까지 발표된 연구 결과는 바이오매스 기반 활성탄의 표면적과 기공부피 이외에 이들의 표면 화학 특성 또한 다양한 분야에 응용될 수 있는 중요한 역할이 있음이 확인된다. 바이오매스 기반 활성탄의 용량은 바이오매스의 특성 및 이들의 활성화 공정에 따라 달라지므로 다양한 응용 분야에 맞게 제조할 수 있다. 따라서 본 리뷰에서는 다양한 분야에 이용되고 있는 바이오매스 기반 활성탄의 역할을 정리하였다.

• Korean Chemical Engineering Research
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• 제57권5호
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• pp.589-595
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• 2019

"파리 협정"을 통해 출범된 신기후체제에 따라 세계 각국에서 온실가스를 감축하기 위한 정책과 연구가 수행되고 있으며, 우리나라에서도 온실가스 감축을 위한 대책 마련이 시급한 실정이다. IEA 보고서에 따르면 에너지 부분의 $CO_2$ 배출량이 전체 배출량의 2/3에 해당하기 때문에 온실가스 감축을 위해서는 단기적으로는 화석연료 사용을 대체할 수 있는 신재생에너의 생산과 적용 기술 개발과 에너지효율개선 기술 도입이 최선이며, 장기적인 관점에서는 온실가스를 포집하고 활용하는 온실가스 포집 및 활용(CCUS, Carbon Capture Utilization and Storage) 기술 개발이 필수적이다. CCUS 기술은 온실가스를 직접적으로 감축시키는 기술로 활발하게 연구되고 있는 기술이다. 본 논문에서는 다양한 CCUS 기술 개요 및 연구 현황과 향후 전망에 대해서 살펴보았다.

• 환경생물
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• 제30권2호
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• pp.121-127
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• 2012

지리산국립공원 산림생태계의 탄소 수지에 관한 기초자료를 확보하기 위해 낙엽활엽수림에 대한 탄소저장량을 추정하였다. 지리산국립공원의 대표 낙엽활엽수림 군락을 중심으로 뱀사골 지구, 중산리 지구, 성삼재 지구로 나누어 조사구 ($30m{\times}30m$, 3지점)를 설치, 식생권과 토양권의 탄소저장량을 추정하였다. 식생권의 탄소량은 $107{\sim}119tC\;ha^{-1}$의 범위로 평균 약 $112tC\;ha^{-1}$ 정도의 양을 축적하고 있다. 또한 토양권의 탄소량은 $64{\sim}77tC\;ha^{-1}$의 범위로 평균 약 $66tC\;ha^{-1}$ 정도의 양을 축적하고 있다. 토양권과 식생권을 포함한 생태계 전체의 탄소저장량은 $167{\sim}184tC\;ha^{-1}$의 범위로 평균 약 $178tC\;ha^{-1}$ 정도의 양을 축적하고 있다. 값의 범위에서 알 수 있듯이 지구별 차이는 크게 나타나지 않았다. 다른 연구 결과와 비교하여 설악산국립공원을 비롯한 강원권 생태계를 제외하고 매우 많은 양의 탄소가 저장되어 있음을 알 수 있다.

• Carbon letters
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• 제15권1호
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• pp.1-14
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• 2014

Carbon nanofibers (CNFs) with diameters in the submicron and nanometer range exhibit high specific surface area, hierarchically porous structure, flexibility, and super strength which allow them to be used in the electrode materials of energy storage devices, and as hybrid-type filler in carbon fiber reinforced plastics and bone tissue scaffold. Unlike catalytic synthesis and other methods, electrospinning of various polymeric precursors followed by stabilization and carbonization has become a straightforward and convenient way to fabricate continuous CNFs. This paper is a comprehensive and brief review on the latest advances made in the development of electrospun CNFs with major focus on the promising applications accomplished by appropriately regulating the microstructural, mechanical, and electrical properties of as-spun CNFs. Additionally, the article describes the various strategies to make a variety of carbon CNFs for energy conversion and storage, catalysis, sensor, adsorption/separation, and biomedical applications. It is envisioned that electrospun CNFs will be the key materials of green science and technology through close collaborations with carbon fibers and carbon nanotubes.

• Korea-Australia Rheology Journal
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• 제21권3호
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• pp.185-191
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• 2009

Polystyrene/multi-walled carbon nanotube (PS/MWCNT) composites were prepared by the use of latex technology. The monodisperse PS latex was synthesized by an emulsifier-free emulsion polymerization from styrene/potassium persulfate/water system in the presence of ethanol. The MWCNTs were first treated with acid mixture to eliminate impurities, dispersed in deionized water driven by ultrasonicator, and then mixed with the PS latex. From these mixtures, PS/MWCNT composites were prepared by freeze-drying and subsequent compression molding. In the small-amplitude oscillatory shear experiments, both complex viscosity and storage modulus increased with increasing MWCNT content. A pronounced effect of MWCNT content was observed, resulting in larger storage modulus and stronger yield behavior at low frequencies when compared to unmodified PS. It showed a transition from viscous to elastic behavior with increasing MWCNT content. Over the MWCNT content of 3 wt%, the storage modulus was higher than the loss modulus across all frequencies.

• Carbon letters
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• 제16권2호
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• pp.127-131
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• 2015

In this work, highly porous carbons were prepared by chemical activation of carbonized biomass-derived aerogels. These aerogels were synthesized from watermelon flesh using a hydrothermal reaction. After carbonization, chemical activation was conducted using potassium hydroxide to enhance the specific surface area and microporosity. The micro-structural properties and morphologies were measured by X-ray diffraction and scanning electron microscopy, respectively. The specific surface area and microporosity were investigated by $N_2$/77 K adsorption-desorption isotherms using the Brunauer-Emmett-Teller method and Barrett-Joyner-Halenda equation, respectively. Hydrogen storage capacity was dependent on the activation temperature. The highest capacity of 2.7 wt% at 77 K and 1 bar was obtained with an activation temperature of $900^{\circ}C$.

• Carbon letters
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• 제12권2호
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• pp.112-115
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• 2011

The scope of this work investigates the relationship between the amount of oxygen-functional groups and hydrogen adsorption capacity with different concentrations of phosphoric acid. The amount of oxygen-functional groups of activated carbons (ACs) is characterized by X-ray photoelectron spectroscopy. The effects of chemical treatments on the pore structures of ACs are investigated by $N_2$/77 K adsorption isotherms. The hydrogen adsorption capacity is measured by $H_2$ isothermal adsorption at 298 K and 100 bar. In the results, the specific surface area and pore volume slightly decreased with the chemical treatments due to the pore collapsing behaviors, but the hydrogen storage capacity was increased by the oxygen-functional group characteristics of AC surfaces, resulting from enhanced electron acceptor-donor interaction at interfaces.