지속저인 산업발전은 화석 연료사용과 에너지 사용을 증가시켰으며, 각 국가별 온실가스 배출은 증가하고 있는 실정이다. 국제사회는 지구 온난화 방지를 위해 1997년 교토 의정서를 채택하였고, 이산화탄소(CO2) 순 배출량 0을 목표로 하여 자체적으로 온실가스 배출 목표를 정하고 실천하고자 2015년 '파리기후변화협정'을 채택하였다. 우리나라는 2015년 '파리기후변화협정' 체결 후 2030년까지 2017년 총 배출량 대비 24.4 % 감축을 목표로 설정하였다.(외교부, 2020) 국내 사회 각 분야에서는 온실가스 감축을 위해 노력하고 있으며, 도로분야에서는 온실가스 저감을 위한 환경친화형 도로 설계와 시 공기술 개발을 위한 연구들이 검토되고 있다. 그 중 가열 아스팔트 혼합물 제조 시 사용되는 기존의 연료(중유, 벙커씨유, 정제유 등) 를 상대적으로 탄소배출량이 적은 연료(LPG, LNG)로 전환하거나, 플랜트 생산온도를 낮추어 사용되는 연료를 저감하는 방법 등 다양 한 연구를 진행하고 있다. 따라서 본 연구에서는 일반 가열 아스팔트 혼합물보다 약 50℃ 낮은 상태에서 생산할 수 있게 도와주는 탄소저감형 첨가제를 적용 한 저가열 아스팔트의 특성을 파악하고자 하였다. 기본 물성시험으로는 연화점, 신도, 회전점도를 시험하였으며, 공용성 등급 시험을 통하여 PG 등급을 확인하였다. 또한 기존에 상용화된 제품과 차이를 보기 위해, 첨가제가 투입되지 않은 일반 아스팔트와 중온 첨가 제 2종(고상형, 액상형)이 적용된 중온 아스팔트도 동일한 시험을 진행하였고, 저가열 아스팔트와 비교·분석 하였다.
As global climate change impacts become more apparent, countries are implementing various policies to achieve carbon neutrality that can be categorized into direct regulations and market-based indirect regulations. The latter, utilizing economic incentives, is considered more efficient in transforming corporate behavior and promoting voluntary efforts for carbon reduction. In alignment with international trends, South Korea has introduced the Emission Trading System (ETS) in 2015. Despite this, the domestic carbon market remains underdeveloped, with low ETS participation, particularly in the aquaculture sector. In order to activate external projects under the ETS, this study proposes short-term strategies including linking ETS with popular eco-friendly energy distribution projects, developing standardized monitoring techniques, and integrating carbon reduction initiatives with other support mechanisms such as direct payment programs. Long-term strategies focus on developing new methodologies for external projects, promoting the use of renewable energy, and enhancing technologies to reduce energy consumption in aquaculture operations. By implementing these strategies, the study aims to enhance the participation of the aquaculture sector in carbon reduction efforts, contributing to the overall goal of carbon neutrality.
We have intended and preparation of hierarchically absorbent materials were covered with a NiMn2O4 and acts as a catalyst for azo dye degradation. The polyaromatic-based (PA) absorbent compounds were initially constructed by bromomethylated aromatic hydrocarbons which undergo self-polymerization in presence of ZnBr as a reagent and cross linker is bromomethyl methyl ether. The absorbent black materials with a 3D network were prepared by direct carbonization and activation of the as-prepared PA. The hydrothermal method was adapted for the preparation of carbon hybrid material C@NiMn2O4 powder's catalytic activity is effective in reducing p-nitrophenol to p-aminophenol and decolorizing carbon-based dyes like methyl orange (MO), methyl yellow (MY), and Congo red (CR) in aqueous media at 25 °C when NaBH4 is added. UV–visible spectroscopy was used to analyze the dyes' breakdown at regular interval.
To fabricate intermetallic nanoparticles with high oxygen reduction reaction activity, a high-temperature heat treatment of 700 to 1,000 °C is required. This heat treatment provides energy sufficient to induce an atomic rearrangement inside the alloy nanoparticles, increasing the mobility of particles, making them structurally unstable and causing a sintering phenomenon where they agglomerate together naturally. These problems cannot be avoided using a typical heat treatment process that only controls the gas atmosphere and temperature. In this study, as a strategy to overcome the limitations of the existing heat treatment process for the fabrication of intermetallic nanoparticles, we propose an interesting approach, to design a catalyst material structure for heat treatment rather than the process itself. In particular, we introduce a technology that first creates an intermetallic compound structure through a primary high-temperature heat treatment using random alloy particles coated with a carbon shell, and then establishes catalytic active sites by etching the carbon shell using a secondary heat treatment process. By using a carbon shell as a template, nanoparticles with an intermetallic structure can be kept very small while effectively controlling the catalytically active area, thereby creating an optimal alloy catalyst structure for fuel cells.
In the current research, a manganese and cobalt oxides-based nanocatalyst was developed which was used to make an efficient cathode electrode for fuel cells. The nano MnOx/ MnCo2O4 was synthesized through a hydrothermal procedure followed by sintering at 500–600 °C. X-ray diffraction and scanning electron microscopy besides electrochemical techniques were applied for the characterization of the synthesized nanocatalyst. The carbon black type Vulcan (XC-72R) and PTFE were used to prepare the active reaction material of the cathode electrode named carbon paste (CP). Loading of the synthesized nano MnOx/ MnCo2O4 on CP was optimized in a weight ratio of 10–90% for the oxygen reduction process in neutral conditions. The best performance was gained for the 50 W% MnOx/ MnCo2O4 loaded CP, whose active surface area was twice the bare CP. The values of the exchange current density of the ORR obtained by electrode containing 50 W% MnOx/ MnCo2O4 was calculated as 0.12 mA/cm2. The low price, good catalytic efficiency, and cyclic stability of the MnOx/ MnCo2O4 nanocatalyst compared to the commercial platinum-based catalysts confirm its ability to develop fuel cell electrodes.
In Korea, as part of the Green New Deal project toward a carbon-neutral society, it is necessary to build a climate-resilient urban environment to green the city, space, and living infrastructure. To this end, SWMM-ING was improved and the model was modified to analyze the carbon reduction effect. In addition, I plan to select target watersheds where urbanization is rapidly progressing and evaluate runoff, non-point pollution, and carbon reduction effects to conduct cost estimation and optimal design review for domestic rainwater circulation green infrastructure. In this study, green infrastructure facilities were selected using SWMM-ING. Various scenarios were presented considering the surface area and annual cost of each green infrastructure facility, and The results show that the scenario derived through the APL2 method was selected as the optimal scenario. In this optimal scenario, a total facility area of 190,517.5 m2 was applied to 7 out of 30 subwatersheds to achieve the target reduction. The target reduction amount was calculated a 23.50 % reduction in runoff and a 26.99 % reduction in pollutant load. Additionally, the annual carbon absorption was analyzed and found to be 385,521 kg/year. I aim to achieve additional carbon reduction effects by achieving the goal of reducing runoff and non-point pollution sources and analyzing annual carbon absorption. Moreover, considering the scale-up of these interventions across the basin, it is believed that an objective assessment of economic viability can be conducted.
본 연구는 유럽연합(EU)의 환경문제와 섬유패션산업 현황을 바탕으로 스페인의 탄소배출 절감 노력과 인디텍스 그룹의 전략을 분석하였다. 특 히 인디텍스 그룹의 사례를 통해 섬유패션산업의 탄소배출 절감 전략의 효과성을 검토하며, 섬유패션산업이 어떻게 지속 가능한 방향으로 전환 될 수 있는지의 시사점을 제시하고자 한다. 특히 석유산업에 이어 두 번 째로 큰 환경 파괴원인으로 지목되는 패스트 패션의 탄소배출 문제를 조 명한다. 연간 전 세계에서 섬유패션산업은 탄소 배출량의 약 10%를 차 지하며, 이 수치는 모든 국제선 및 해상 운송의 배출량을 합친 것보다도 더 크다. 특히 패스트 패션의 생산과 유통 과정에서 발생하는 탄소배출 은 그 크기가 막대하여 지속가능성에 큰 위협을 미치고 있다. 즉, 패스트 패션의 탄소배출 문제를 해결하기 위한 전략적 접근 방식을 제시하며, 섬유패션산업의 지속가능성 향상을 위한 핵심 요소를 도출하고자 한다.
Instead of using expensive platinum, carbon anodes could potentially be utilized in the process of reducing oxides in LiCl-Li2O molten salt at a high cell potential. However, this high potential leads to the generation of a mixture of anodic gases containing toxic and corrosive gases such as chlorine (Cl2), oxygen (O2), carbon monoxide (CO), and carbon dioxide (CO2). To better understand this gas mixture, we conducted real-time analyses of the gases generated on the carbon anode during the TiO reduction reaction in the molten salt at 650°C, using a MAX-300-LG gas analyzer. Our results indicate that the ratio of CO/O2/CO2/Cl2 in the gas mixture is significantly influenced by the composition of the salt, and that removing the sources of oxygen ions in the salt increases the likelihood of generating toxic and corrosive Cl2 gas.
Nitrophenol sensors have garnered interest in pharmaceuticals, agriculture, environment safety and explosives. Various methods have been proposed to detect 4-nitrophenol, but nitrophenol isomers such as 2,4-dinitrophenol (DNP) and 2,4,6-trinitrophenol have been comparatively less studied. For the first time, the present work explores graphitic nanocarbon, i.e., carbon black (CB) interface for sensing of DNP. Two reduction potentials were noted at − 0.48 and − 0.64 V for o-NO2 and p-NO2 moieties, respectively, at CB/GCE. At the same time, bare GCE (glassy carbon electrode) shows a single reduction potential at − 0.7 V. The electrocatalytic effect and adsorption ability of the interface was studied from the DNP concentration effect. Scan rate and pH studies suggest that the CB acquires four electrons for NO2 reduction by the diffusion phenomenon. A broad detection range of 10–250 μM DNP with a very low detection limit of 0.13 (o-form) and 0.15 μM (p-form) was achieved using the CB interface. The real-time applicability of the fabricated sensor was evaluated using commercially available beverages with excellent recovery values. The stability, repeatability and reproducibility of the CB interface were successfully confirmed. Comparison of the sensing parameters of the developed sensor with those reported in literature reveals excellent detection limit and response time for the CB-interfaced DNP sensor, indicating its potential for environmental and commercial applications.
One-step hydrothermal reduction method was used to prepare three-dimensional carbon fiber brush-based graphene–platinum (CFB/Pt–G) composites to improve the electrocatalytic oxygen reduction activity of cathode materials for seawater oxygen-dissolved battery. Characterization results show that the reduced graphene oxide of as-prepared graphene–platinum composite displays the few-layer folded structure. In addition, Pt nanoparticles with the polycrystalline structure dispplay a preferential growth along the crystal plane of (111) and are mainly distributed around the defect cavities of folded graphene. Electrochemical results show that the diffusion-limited current density of CFB/Pt–G composite tested with 1600 rpm/min in 3.5% NaCl solution reaches 5 mA/cm2, while that of CFB/G is only 2.64 mA/cm2. Battery discharge results show that the maximum volume power density of CFB/Pt–G–Mg battery with a stable open voltage of 1.73 V is 81 times as much as the commercial seawater battery SWB1200.
The reaction between Li2CO3 and Cl2 was investigated to verify its occurrence during a carbon-anode-based oxide reduction (OR) process. The reaction temperature was identified as a key factor that determines the reaction rate and maximum conversion ratio. It was found that the reaction should be conducted at or above 500℃ to convert more than 90% of the Li2CO3 to LiCl. Experiments conducted at various total flow rate (Q) / initial sample weight (W i) ratios revealed that the reaction rate was controlled by the Cl2 mass transfer under the experimental conditions adopted in this work. A linear increase in the progress of reaction with an increase in Cl2 partial pressure (pCl2) was observed in the pCl2 region of 2.03–10.1 kPa for a constant Q of 100 mL∙min−1 and W i of 1.00 g. The results of this study indicate that the reaction between Li2CO3 and Cl2 is fast at 650℃ and the reaction is feasible during the OR process.
The corrosion behavior of Hastelloy C-276 was investigated to identify its applicability for carbon-anode-based oxide reduction (OR), in which Cl2 and O2 are simultaneously evolved at the anode. Under a 30 mL·min-1 Cl2 + 170 mL·min-1 Ar flow, the corrosion rate was less than 1 g·m-2·h-1 up to 500℃, whereas the rate increased exponentially from 500 to 700℃. The effects of the Cl2-O2 composition on the corrosion rate at flow rates of 30 mL·min-1 Cl2, 20 mL·min-1 Cl2 + 10 mL·min-1 O2, and 10 mL·min-1 Cl2 + 20 mL·min-1 O2 with a constant 170 mL·min-1 Ar flow rate at 600℃ was analyzed. Based on the data from an 8 h reaction, the fastest corrosion rate was observed for the 20 mL·min-1 Cl2 + 10 mL·min-1 O2 case, followed by 30 mL·min-1 Cl2 and 10 mL·min-1 Cl2 + 20 mL·min-1 O2. The effects of the chlorine flow rate on the corrosion rate were negligible within the 5–30 mL·min-1 range. A surface morphology analysis revealed the formation of vertical scratches in specimens that reacted under the Cl2-O2 mixed gas condition.
The corrosion behavior of the Inconel X-750 alloy was investigated for its potential application under a Cl2-O2 mixed gas flow in an Ar atmosphere. The corrosion rate was found to be negligible at temperatures up to 400℃ under a flow rate of 30 mL·min-1 Cl2 + 170 mL·min-1 Ar, whereas an exponential increase was observed in the corrosion rate at temperatures greater than 500℃. The suppression of the corrosion reaction due to the presence of O2 was verified experimentally at flow rates of 30 mL·min-1 Cl2 (4.96 g·m-2·h-1), 20 mL·min-1 Cl2 + 10 mL·min-1 O2 (2.02 g·m-2·h-1), and 10 mL·min-1 Cl2 + 20 mL·min-1 O2 (1.34 g·m-2·h-1) under a constant Ar flow rate of 170 mL·min-1 at 600℃ for 8 h. The surface morphology analysis results revealed that porous surfaces with tunnel-type holes were produced under the Cl2-O2 mixed-gas condition. Furthermore, the effects of the Cl2 flow rate on the corrosion rate were investigated, indicating that its impact was negligible within the range of 5–30 mL·min-1 Cl2 at 600℃.
Here, the stability of stainless steel 316 (SS-316) was investigated to identify its applicability in the oxide reduction process, as a component in related equipment, to produce a complicated gas mixture composed of O2 and Cl2 under an argon (Ar) atmosphere. The effects of the mixed gas composition were investigated at flow rates of 30 mL/min O2, 20 mL/min O2 + 10 mL/min Cl2, 10 mL/min O2 + 20 mL/ min Cl2, and 30 mL/min Cl2, each at 600℃, during a constant argon flow rate of 170 mL/min. It was found that the corrosion of SS-316 by the chlorine gas was suppressed by the presence of oxygen, while the reaction proceeded linearly with the reaction time regardless of gas composition. Surface observation results revealed an uneven surface with circular pits in the samples that were fed mixed gases. Thermodynamic calculations proposed the combination of Fe and Ni chlorination reactions as an explanation for this pit formation phenomenon. An exponential increase in the corrosion rate was observed with an increase in the reaction temperature in a range of 300 ~ 600℃ under a flow of 30 mL/min Cl2 + 170 mL/min Ar.
본 연구는 L-alanine을 적용한 스크러버의 주류공장 내 CO2 제거효율, 모니터링 데이터 분석/ 평가 및 에너지 저감효율을 평가하였다. 스크러버의 평균 제거율은 90.45%로 10,000 ppm이상의 고농도 CO2가 유입됨에도 제거효율이 뛰어난 것을 확인하였다. 스크러버 작동 후 작업장 내 CO2는 2,000ppm 이 하로 유지하여 약 74% 이상의 이산화탄소 저감 효율을 확인하였다. 또한 소비되는 전력량을 측정한 결과 스크러버 작동 후 230 kWh로 약 7.26%의 에너지가 절감되는 것으로 나타났다. 즉, 본 개발제품을 적용한 결과로 작업장 내 이산화탄소 농도를 외기유입 없이 낮은 농도로 유지함에 따라 근무자의 작업환경을 개선 시킬 수 있었으며 에너지 소비량 또한 저감할 수 있었다. 그러므로 식품, 주류공장 내 고농도 CO2 제거 공 정으로써 스크러버가 유용할 것으로 기대된다.