• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.25-31
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• 2013

Hydrogen peroxide takes much of the cost for Fenton reaction applied for treatment of organic contaminants. Therefore, the effective use of hydrogen peroxide makes the technology more cost effective. The effective use of hydrogen peroxide is especially needed in the soil and groundwater remediation where complete mixing is not possible and it takes a long time for reactive species to transport to the fixed target compounds. Stabilization ability for hydrogen peroxide of malonic acid was evaluated in Fenton and Fenton-like reactions in this study. Malonic acid contributes on the stabilization of hydrogen peroxide by weak interaction between iron and the stabilizer and inhibiting the catalytic role of iron. The stabilization effect increased as the solution pH decrease below the $pK_{a1}$. The stabilization effect increased as the concentration of malonic acid increased and the effect was maximized at the malonic acid concentration of about ten times higher than the iron concentration. The model organic contaminant was successfully oxidized in the presence of the stabilizer but the degradation rate was slower than the system without the stabilizer. The stabilization effect was also proved in a Fenton-like reaction where magnetite and hematite were used instead of soluble iron species.

• 한국수소및신에너지학회논문집
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• 제34권3호
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• pp.256-266
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• 2023

Hydrogen production can be classified based on the energy source, primary reactor type, and whether or not it emits carbon dioxide. Utilizing color representation proves to be an effective means of expressing these distinctive characteristics. Among the various clean hydrogen production techniques, there has been a growing interest in turquoise hydrogen production, which involves the decomposition of methane or other fossil fuels. This method offers advantages in terms of large-scale production and cost reduction through the sale of solid-carbon byproduct. In this study, an extensive literature review was conducted to select and analyze several promising candidates for turquoise hydrogen production processes. The efficiency and economics of these processes were evaluated using stream data reported in the literature sources. The findings indicate that the levelized cost of hydrogen production (LCOH) is significantly influenced by the sales of byproducts, specifically the solid-carbon and carbon monoxide byproducts.

• 한국수소및신에너지학회논문집
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• 제13권4호
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• pp.330-338
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• 2002

A long-term energy system in the future is expected to be based on the ideal circulation system between water and hydrogen in the sense that the hydrogen prepared from water eventually returns to water again after its use. Currently, with respect to the hydrogen energy system, it is predicted that the turning-point at which the production cost of hydrogen will become to be lower than that of fossil fuels would be after 2010. However, fuel cell technology would be able to be practically used for the applications to the transportation vehicles and small-scale power sources from 2004, and therefore, an efficient construction of the infrastructure covering hydrogen production and supply systems would be required with short-/mid-term technologies for the $CO_2$ reduction associated with fossil fuel utilization. In this paper, the hydrogen quantity available in domestic market has been estimated focusing on the hydrogen by-produced from domestic industries, and also the infrastructure for hydrogen-driven vehicles like fuel cell cars has been reviewed.

• 한국수소및신에너지학회논문집
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• 제31권6호
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• pp.522-529
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• 2020

This study evaluated the effect of improving the atmospheric environment based on the premise that the supply of hydrogen fuel cell vehicles (HFCV) will be achieved as many as the number of vehicles presented in the hydrogen economy activation roadmap announced by the Korean government in January 2019. The HFCV supply target (2.7 million passenger cars) suggested in the hydrogen economy revitalization roadmap was logically allocated to the five major metropolitan areas in Korea. Air pollution damage costs by region were calculated by reflecting the basic unit of damage cost to the estimated air pollutant emissions. As a result, it was confirmed that the benefits per unit of some cities in Gyeonggi-do were derived more than major cities in the metropolitan area.

• 한국수소및신에너지학회논문집
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• 제19권2호
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• pp.145-155
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• 2008

This paper deals with an economic evaluation of hydrogen production by fermentation. We evaluate the economic feasibility of domestic hydrogen production by fermentation utilizing glucose and waste water sludge in terms of hydrogen production prices. In addition, we make some sensitivity analysis of hydrogen prices by changing the values of input factors such as the price of glucose, the capital cost of the hydrogen production system, and the hydrogen production yields. The estimated hydrogen prices of the two-step dark-light hydrogen production by fermentation utilizing glucose was $5,347won/kgH_2$, and the single-step hydrogen production by anaerobic fermentation utilizing waste water sludge was $4,255won/kgH_2$, respectively. It is expected that the hydrogen production price by anaerobic fermentation can be reduced if we produce methane or hydrogen utilizing by-products such as alcohols and organic acids, or the government imposes some legal regulations on the treatment of waste water sludge.

• 한국수소및신에너지학회논문집
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• 제22권4호
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• pp.458-464
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• 2011

Recently, one of the hydrogen production methods has attracted using dense metallic membrane. It has high hydrogen permeation and selectivity which hardly could adopt industrial product because of high cost, hydrogen embrittlment and thermal stability. Meanwhile, vanadium has high hydrogen solubility and it use to instead of Pd-Ag amorphous membrane. Aluminum carried out blocking hydrogen diffusion on grain boundary therefore protecting hydrogen embrittlement. Most of dense metallic membrane is solution diffusion mechanism. The solution diffusion mechanism was very similar hydrogen storing steps such as steps of metal hydride. Thus, V-Al composites were fabricated to use hydrogen induced mechanical alloying. The fabricated V-Al composites were characterized by XRD, SEM, EDS and simultaneous TG/DSC analyses. The hydrogenation behaviors were evaluated using a Sievert's type automatic PCT apparatus. The hydrogenation behaviors of V-Al composites was evaluated too low hydrogen stored capacity and fast hydrogenation kinetics. In PCI results, V-Al composites had low hydrogen solubility, in spite of that, hydrogen kinetics was calculated very fast and hydrogen absorption/desorption contents were same capacity.

• 한국수소및신에너지학회논문집
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• 제18권4호
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• pp.464-480
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• 2007

There are several methods for the hydrogen production such as steam reforming of natural gas, photochemical method, biological method, electrolysis and thermochemical method, etc. These days it has been widely studied for the hydrogen production method having low hydrogen production cost and high efficiency. In this paper, patents in the hydrogen production by steam reforming of natural gas were gathered and analyzed. The search range was limited in the open patents of USA(US), European Union(EP), Japan(JP), and Korea(KR) from 1996 to 2006. Patents were gathered by using key-words searching and extracted by filtering criteria. The trends of the patents was analyzed by the years, countries, companies, and technologies.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권2호
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• pp.116-121
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• 2006

This paper presents an effective modeling and simulation scheme of solar-powered hydrogen production system (PV-SPE: Photovoltaic Solid Polymer Electrolyte). Existing Hydrogen production technologies can produce vast amounts of hydrogen from hydrocarbons but emit large amounts of carbon dioxide (CO2) into the atmosphere. Advanced hydrogen production methods need development. Renewable technologies such as solar and wind need further development for hydrogen production to be more cost-competitive from other resources. In this paper, authors have focused on a renewable technology to move one step further toward commercial readiness of solar-powered hydrogen production system. Software (PSCAD/EMTDC) based model of PV-SPE system is studied for an effective simulation of hydrogen production system. Using the simulation results, an actual PV-SPE system is implemented to verify the simulation results by comparing them with actual values obtained from the data acquisition system.

• 한국수소및신에너지학회논문집
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• 제18권1호
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• pp.95-108
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• 2007

There are several methods for the hydrogen production such as steam reforming of natural gas, photocatalytic method, biological method, electrolysis and thermochemical method, etc. These days it has been widely studying for the hydrogen production method having low hydrogen production cost and high efficiency. In this paper, patents in the hydrogen production by water electrolysis were gathered and analyzed. The search range was limited in the open patents of USA(US), European Union(EP), Japan(JP), and Korea(KR) from 1996 to 2005. Patents were gathered by using key-words searching and filtered by filtering criteria. The trends of the patents was analyzed by the years, countries, companies, and technologies.

• 한국재료학회지
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• 제29권5호
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• pp.297-303
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• 2019

A triple-layered $PMMA/Ni_{64}Zr_{36}/PDMS$ hydrogen gas sensor using hydrogen permeable alloy and flexible polymer layers is fabricated through spin coating and DC-magnetron sputtering. PDMS(polydimethylsiloxane) is used as a flexible substrate and PMMA(polymethylmethacrylate) thin film is deposited onto the $Ni_{64}Zr_{36}$ alloy layer to give a high hydrogen-selectivity to the sensor. The measured hydrogen sensing ability and response time of the fabricated sensor at high hydrogen concentration of 99.9 % show a 20 % change in electrical resistance, which is superior to conventional Pd-based hydrogen sensors, which are difficult to use in high hydrogen concentration environments. At a hydrogen concentration of 5 %, the resistance of electricity is about 1.4 %, which is an electrical resistance similar to that of the $Pd_{77}Ag_{23}$ sensor. Despite using low cost $Ni_{64}Zr_{36}$ alloy as the main sensing element, performance similar to that of existing Pd sensors is obtained in a highly concentrated hydrogen atmosphere. By improving the sensitivity of the hydrogen detection through optimization including of the thickness of each layer and the composition of Ni-Zr alloy thin film, the proposed Ni-Zr-based hydrogen sensor can replace Pd-based hydrogen sensors.