본 연구에서는 온실가스 배출을 감축하기 위해 메탄올을 추진 연료로 사용하는 선박에 수소 연료전지 시스템이 추가된 하 이브리드 시스템 공정을 설계하였다. Case1에서는 메탄올 연료 엔진 시스템을 설계하여, 엔진에 가솔린 대신 메탄올을 연료로 공급했 을 때의 배기가스 배출량을 알아보았다. Case2에서는 Case1에 메탄올 개질 시스템을 추가해, 수소연료전지 시스템을 설계하였다. 이 하 이브리드 시스템에서는 그레이 수소를 생산하며, 엔진과 연료전지의 출력을 조합하여 선박을 구동한다. 하지만 그레이 수소는 수소를 생산하는 과정에서 탄소를 배출한다는 단점이 있다. 이 점을 보안하기 위해 Case3에서는 CCU시스템을 추가하였다. Case2에서 배출한 Flue gas의 이산화탄소를 포집한 후, 그레이 수소와 합성해 블루 메탄올을 생산하였다. 본 연구에서는 Case study를 통해 개질 온도22 0℃, 개질 압력500kPa, SCR은 1.0, flow ratio가 0.7일 때 최적의 운전조건임을 알 수 있었다. Case3의 시스템은 Case1에 비해 탄소 배출량 을 42% 감소시켰다. 결과적으로, Case3의 하이브리드 시스템을 통해 선박의 이산화탄소 배출을 유의미하게 저감할 수 있을 것으로 예 상한다.

Polyacrylonitrile (PAN)-based carbon fibers (CFs) and their composites, CF-reinforced plastics, have garnered significant interest as promising structural materials owing to their excellent properties and lightweight. Therefore, various processing technologies for fabricating these advanced materials using thermal energy have been intensively investigated and developed. In most cases, these thermal energy-based processes (heat treatment) are energy and time consuming due to the inefficient energy transfer from the source to materials. Meanwhile, advanced processing technologies that directly transfer energy to materials, such as radiation processing, have been developed and applied in several industrial sectors since the 1960s. Herein, general aspects of radiation processing and several key parameters for electron-beam (e-beam) processing are introduced, followed by a review of our previous studies pertaining to the preparation of low-cost CFs using specific and textile-grade PAN fibers and improvements in the mechanical and thermal properties of CF-reinforced thermoplastics afforded by e-beam irradiation. Radiation processing using e-beam irradiation is anticipated to be a promising method for fabricating advanced carbon materials and their composites.

The production of macroalgae-derived adsorbent is of great importance to realize the idea of treating pollutants with invaluable renewable materials. Herein, a novel meso-micro porous nano-activated carbon was prepared from green alga Ulava lactuca in a facile way via chemical activation with zinc chloride. The resultant activated carbon possesses a significant specific surface area 1486.3 m2/ g. The resulting activated carbon was characterized and investigated for the adsorption of Direct Red 23 (DR23) dye from an aqueous environment. Batch method was conducted to study the effects of different adsorption processes on the DR23 dye adsorption from water. Isotherms and kinetics models were investigated for the adsorption process of DR23 dye. It was found that the adsorption data were well fitted by Langmuir model showing a monolayer adsorption capacity 149.26 mg/g. Kinetic experiments revealed that the adsorptions of DR23 dye can be described with pseudo-secondorder model showing a good correlation (R2 > 0.997). The prepared activated carbon from Ulava lactuca was exposed to a total of six regeneration experiments. The regeneration result proved that the fabricated activated carbon only loses 19% of its adsorption capacity after six cycles. These results clearly demonstrated the high ability of the obtained active carbon to absorb anionic dyes from the aqueous environment.

Increasing demand for fossil fuels is associated with massive atmospheric CO2 levels. Considering that numerous studies have been published with CO2 capturing techniques, utilizing techniques are yet in early stage with financial or technical issues. As a part of chemical conversion in CO2 utilization, this paper investigated the performance of a CO2 and H2O mixture (CHM) onto activated carbon fibers (ACF) for surface modification. CHM-treated ACF samples were prepared at a pressure of 20 bar with 100 °C of water vapor and 750 μL of CO2 for 1 h through the gas-phase, and labeled as C-ACF850. For the control sample, N-ACF850 was also prepared by the impregnation of nitric acid. Physiochemical analyses revealed that the overall characteristics of C-ACF850 lay between ACF850 and N-ACF850. C-ACF850 experienced minimized surface area decrement (21.92% better than N-ACF850), but increased surface functional groups (50.47% better than ACF850). C-ACF850 also showed preferable adsorption efficiency on selected metals, in which case both physical and chemical properties of adsorbent affect the overall adsorption efficiency. In this regard, a novel applicability of CHM may present an appealing alternative to traditionally used strong acids.

2015년 파리기후변화협약에 의한 신기후체제 출범으로 전세계 195개국이 온실가스 감축을 약속하게 되었다. 한국도 2013년 기준 온실가스 배출이 7억톤을 기록하고 있으며 BAU대비 37% (3.1억 톤)를 감축해야 하는 의무를 약속하고 있다. 국내외에서 철강, 화학, 환경산업 등에서 대량으로 배출되는 온실가스를 회수하여 화학제품을 생산하는 탄소자원화(carbon resources utilization) 연구가 활발히 진행되고 있다. 본 발표에서는 온실가스를 포함한 다양한 조성의 산업부 생가스의 발생현황과 부생가스로부터 고순도의 이산화탄소, 일산화탄소, 메탄, 수소 등을 경제적으로 분리회수하여 화학원료가스로 사용할 수 있는 분리기술 의 연구동향과 한국화학연구원에서 수행하고 있는 바이오가스 막분리기술을 중심으로 소개하고자 한다.

Four activated carbons were produced by two-stage process as followings; semi-carbonization of indigenous biomass waste, i.e. cotton stalks, followed by chemical activation with KOH under various activation temperatures and chemical ratios of KOH to semi-carbonized cotton stalks (CCS). The surface area, total pore volume and average pore diameter were evaluated by N2-adsorption at 77 K. The surface morphology and oxygen functional groups were determined by SEM and FTIR, respectively. Batch equilibrium and kinetic studies were carried out by using a basic dye, methylene blue as a probe molecule to evaluate the adsorption capacity and mechanism over the produced carbons. The obtained activated carbon (CCS-1K800) exhibited highly microporous structure with high surface area of 950 m2/g, total pore volume of 0.423 cm3/g and average pore diameter of 17.8 a. The isotherm data fitted well to the Langmuir isotherm with monolayer adsorption capacity of 222 mg/g for CCS-1K800. The kinetic data obtained at different concentrations were analyzed using a pseudo-first-order, pseudo-second-order and intraparticle diffusion equations. The pseudo-second-order model fitted better for kinetic removal of MB dye. The results indicate that such laboratory carbons could be employed as low cost alternative to commercial carbons in wastewater treatment.

To get more comprehensive understandings about the microbial diversity near the seawater of Ulleung Island, East sea of Korea, the bacterial identification base on 16S rDNA and their carbon source utilization patterns were analysed through the six surface water samples collected at June 23 to 25, 2007. The results are as follows; the population densities of aerobic heterotrophic and oligotrophic bacteria were from 1.9±0.6×104~6.3±0.7 ×104 cfu ml−1 and from 1.7±0.4×103~2.5±0.4×103 cfu ml−1 during sampling periods, respectively. Among 121 isolated stains, the dominant taxa are Pseudoalteromonas spp. (30 colonies) and Alteromonas spp. (17 colonies). Thirty-senven species-level strains base on 16S rDNA sequencing data are identified, which comprised Gammaproteobacteria (14 strains), Alphaproteobacteria (6 strains), Flavobacteria (6 strains), Actinobacteridae (4 strains), Firmicutes (4 strains), Deinococci (2 strains), Betaproteobacteria (1 strains). The carbon utilization patterns by assay of Biolog-microplate, α-D-glucose are used by 88.9% of the 27 strains of Gram-negative bacteria and more than 80% of them also consumed L-arabinose, D-trehalose, L-alanine, and pyruvic acid methyl ester. On the other hand, all the 10 strains of Gram-positive bacteria used α-D-glucose, and more than 80% of them also exploited maltose, palatinose, D-trehalose, turanose, D-xylose, and pyruvic acid.

서울시 지하수중 중금속 등으로 오염되어 음용 이외의 생활용수로 사용하고 있는 8개 정점과 음용수로 사 용하고 있는 2개 정점을 대상으로, 세균 군집 대사 다양성의 변화를 유일 탄소원 이용능의 변화 양상으로 분석하였다. Biolog GN plate에서 발색 반응이 안정화된 배양 시간은 155시간 이후로 나타났다. 음용수로 사용하는 정점이 생활용수로 사용하는 정점의 발색 반응값 보다 높게 나타났다. 지하수 세균 군집은 polymer, carbohydrate, ester 및 amino acid를 공통적으로 많이 이용하였으나, brominated chemicals과 phosphorylated chemicals를 이용하는 세균 군집은 적게 나타났다. 다변량 통계학적 분석을 통한 세균 군집의 대사 다양성 분석 결과, 모두 5개 그룹인 음용수 정점, 휘발성 오염 정점, 크롬 오염 정점, 질산성 질소 오염 정점과 비소 오염 정점으로 구분이 가능하였다. 오염물질에 따른 세균 군집의 탄소원 이용능의 차이로 볼 때, 오염원에 따라 세균 군집의 대사 다양성이 변화하고 있음을 확인하였다.

산업혁명 이후로 계속해서 문제가 되어왔던 이산화탄소를 저감하기 위한 노력이 전세계적으로 이루어지고 있다. 다양한 이산화탄소 저감 기술 중 이산화탄소를 안정적이고 대량으로 고정 및 재이용할 수 있는 기술 중 하나로 무기탄산화 기술이 있는데 이는 금속이온과 이산화탄소를 반응시켜 무기탄산염을 생성하는 기술이다. 따라서 금속이온 공급원 선택이 핵심 요소 중 하나인데 일반적으로 Mg2+, Ca2+, K+, Na+ 등을 포함한 다량의 금속 이온을 포함하고 있는 해수를 기반으로 한 폐기물의 사용에 대하여 고려하였다. 정제소금 생산 공정에서는 위에 언급된 해수를 사용하여 소금을 생산한다. 이러한 과정에서 Na+가 제거되면서 Mg2+ 및 Ca2+가 농축된다. 따라서 기존의 해수보다 높은 농도의 금속 이온을 가지고 있기 때문에 사용하기에 적합하며 폐수처리라는 장점 또한 가지고 있다. 먼저 해수 내의 Ca이온을 OH-이온을 사용한 pH조절을 통하여 Ca(OH)2로 분리한 후 CO2 포화 아민계 흡수제(Methyldiethanolamine, MDEA)를 사용하여 이산화탄소를 전달한다. 생성물을 여과한 후 고온에서 24시간 건조시킨 후에 XRD, SEM, TGA를 사용하여 결정구조, 모양 및 순도분석을 실시하였다. 또한 포화 아민계 흡수제 제조 과정에서 재이용 가능성을 확인하기 위하여 탈거 및 재흡수실험을 진행하였다.

폐시멘트, 폐콘크리트, 제강 슬래그, 폐수 등을 포함하여 다양한 폐기물들이 여러 산업으로부터 배출되고 있다. 그런데 이러한 폐기물들은 Mg2+ 이온, Ca2+ 이온을 다량 포함하고 있다고 알려져 있다. 폐기물 처리 시 이러한 금속 이온을 활용한다면 MgCO3, CaCO3 등 다른 유용한 물질로 전환시킬 수 있다. 이를 위해 지구온난화를 일으키는 주요 원인으로 알려진 이산화탄소를 사용할 수 있고, 이는 이산화탄소 저감 및 폐기물 처리를 동시에 해결할 수 있을 것으로 보인다. 본 연구에서는 CO2의 용이한 전달을 돕기 위한 습식 흡수제에 대해 제안하고 Henry constant, Diffusivity, 총괄반응속도상수(kov)를 측정하였다. 흡수제는 7 wt% 암모니아, 3 wt% ʟ-Arginine, 1 wt% 부식방지제(Imidazole과 1,2,3-Benzotriazole)를 물에 녹여 제조하였다. 암모니아는 기존에 습식흡수제로 사용되던 MEA보다 저렴한 가격을 가지고 있으며 CO2 흡수 능력 또한 우수하다고 알려져 있다. 최근 아미노산은 우수한 CO2 흡수능력과 친환경적인 특성으로 많은 연구가 진행되고 있으며 두 종류의 부식방지제는 암모니아에 의해 발생할 수 있는 플랜트 장비의 부식을 방지하기 위해 첨가되었다. 303.15 K에서 333.15 K의 온도에서 실험이 진행되었으며 실험 결과와 CO2/N2O analogy를 이용해 각 값을 계산하였다.

Many researchers around the worlds are getting their attention on developing carbon dioxide reduction technologies. In this research, the method to utilize captured carbon dioxide was suggested using industrial wastewater which was produced from refined salt production process. High concentrations of metal carbonates such as calcium, magnesium and so on were contained in them and it could lead to carbon fixation which can lead to utilization of precipitated salts for various purposes. In this research, 30 wt% of monoethanolamine, diethanolamine and methyl-diethanolamine solutions were used as absorbents and precipitated salts were produced as final product. Using X-ray diffraction and Scanning Electron Microscope, crystal structures of the products were verified.

The concentration of carbon dioxide in atmosphere is gradually increasing as industrial activity is being facilitated. Since most of the industries are getting their energy from fossil fuels such as coal, petroleum and gas, carbon dioxide production is inevitable. However, by applying suitable carbon capture process at the end of the carbon dioxide emission facilities, the amount of carbon dioxide emitted to atmosphere can be significantly reduced. Thus, Carbon Capture and Storage (CCS) technologies have been developed by many nations. In that technology, captured carbon dioxide is stored in deep ocean or the underground holes. However, considering environmental effects and geological distinct characteristics, CCS technologies are thought to be developed finding new way to handle captured carbon dioxide. One of the method is to turn captured carbon dioxide into precipitated calcium carbonate salt by adding calcium ions. Conventionally, calcium carbonate salt formation is achieved by reaction under high pressure and temperature. However, this method requires large amount of energy to maintain reaction condition. Hence, carbon dioxide reduction and utilization technology through carbon fixation or carbonation in aqueous phase is proposed in this research. Using aqueous absorbent, carbon dioxide is captured and precipitated calcium carbonate salt was formed by adding calcium ions. All of the reaction occurred under ambient temperature and pressure (1 atm, 298.15 K). The amount of carbon dioxide reduction as well as yield of precipitated calcium carbonate salt were considered. Also, through instrumental analysis including Scanning Electron Microscope (SEM), X‐Ray Diffraction (XRD) and Thermogravimetric Analysis (TGA), possibility of final product utilization was investigated.

This study was attempted to evaluate the change of microbial community in inoculums, lag, and stationary phase using the community level physiological profiles (CLPP) base on C-substrate utilization. It was to ascertain the characterizing microbial community over time in the enrichment step of microbial fuel cells. Microbial fuel cell is a device that converts chemical energy to electricity with aid of the catalytic reaction of microorganisms using C-substrate included wastewater. Microbial fuel cells enriched by a mixture of anaerobic digestive sludge of the sewage treatment plant and livestock wastewater were used. The current after enrichment was generated about 0.84 ± 0.06 mA. Microbial community in inoculums, lag and stationary phase used amine group, phosphorylated chemical group, and carboxylic acid group (some exclusion). However, phenolic compound did not use by microorganisms in lag and stationary phase. It means that there are not the microorganisms capable of decompose the phenol in microbial fuel cell enriched by livestock wastewater. In case of substrates of amino acid and carbohydrates group, these C-substrates were only used by microorganisms in the stationary phase. It may be that electrochemically active microorganisms (EAM) which we want to know should utilize the better these C-substrates than that of lag phase. This study showed that the electrochemically active bacteria that can be distinguished by electron changes of C-substrate utilization over time could be separated.