• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.965-970
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• 2008

The separation of sulfone components using light cycle oil(LCO) after oxidation was carried out by solvent extraction method using various polar solvents such as water, n-methyl-2-pyrrolidone(NMP), dimethyl sulfoxide, ethyl acetate, acetonitrile, dimethyl formamide, and methyl alcohol. It was found that phase separation between LCO layer and solvent occurred under mixed solvent adding a proper amount of water. The mixture solvent of NMP and water was a promising extraction solvent due to the selective removal and high distribution coefficient of sulfone component in LCO. 99.5% over of sulfur contents in LCO can be removed by 4 stages equilibrium extraction.

• Microbiology and Biotechnology Letters
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• v.47 no.1
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• pp.116-124
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• 2019

The rapid development of the poultry industry has led to the production of large amounts of manure, which produce substances like hydrogen sulfide ($H_2S$) that contribute to odor pollution. $H_2S$ is a highly undesirable gas component and its removal from the environment is therefore necessary. Sulfur-oxidizing bacteria (SOB) are widely known to remove contaminating $H_2S$ due to their ability to oxidize reduced sulfur compounds. In this study, three potential SOB (designated AH18, AH25, and AH28) that were previously isolated from a hot spring in Malaysia were identified by 16S rRNA gene analysis. Laboratory-scale biological deodorization experiments were conducted to test the performance of the three isolates-in the form of pure or mixed cultures, with the cells immobilized onto alginate as a carrier-in reducing the $H_2S$ from chicken manure. On the basis of 16S rRNA phylogenetic analysis, isolate AH18 was identified as Pseudomonas sp., whereas isolates AH25 and AH28 were identified as Achromobacter sp. The most active deodorizing isolate was AH18, with an $H_2S$ reduction rate of 74.7% (p < 0.05). Meanwhile, the reduction rates for isolates AH25 and AH28 were 54.2% and 60.8% (p > 0.05), respectively. However, the $H_2S$ removal performance was enhanced in the mixed culture, with a reduction rate of 81.9% (p < 0.05). In conclusion, the three potential SOB isolates were capable of reducing the $H_2S$ from chicken manure in the form of a pure culture immobilized on alginate, and the reduction performance was enhanced in the mixed culture.

• Korean Chemical Engineering Research
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• v.54 no.3
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• pp.419-424
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• 2016

$H_5PMo_{10}V_2O_{40}$ ($PMo_{10}V_2$) catalyst chemically immobilized on sulfur-containing mesoporous carbon (S-MC) was prepared, and it was applied to the benzyl alcohol oxidation reaction. S-MC was synthesized by a templating method using SBA-15 and p-toluenesulfonic acid as a templating agent and a carbon precursor, respectively. S-MC was then modified to have a positive charge, and thus, to provide sites for the immobilization of $PMo_{10}V_2$. By taking advantage of the overall negative charge of $[PMo_{10}V_2O4_{40}]^{5-}$, $PMo_{10}V_2$ catalyst was immobilized on the S-MC support as a charge matching component. It was revealed that $PMo_{10}V_2$ species were finely and molecularly dispersed on the S-MC via chemical immobilization. In the vapor-phase oxidation of benzyl alcohol, $PMo_{10}V_2$/S-MC catalyst showed higher conversion of benzyl alcohol and higher yield for benzaldehyde and benzoic acid than unsupported $PMo_{10}V_2$ catalyst. The enhanced catalytic performance of $PMo_{10}V_2$/S-MC was due to fine dispersion of $PMo_{10}V_2$ species on the S-MC via chemical immobilization.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.2
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• pp.201-208
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• 2010

The $SO_2$ and $NO_x$ removal with an activated coke catalyst was conducted by a two-stage reaction which first $SO_2$ was oxidized to $H_2SO_4$ and then $NO_x$ was reduced to $N_2$. But if unreacted sulfur dioxide entered in the second stage, the $NO_x$ reduction was hindered by the reaction with ammonia. In this study, experimental investigations by using lab-scale column apparatus on the product and the reactivity of $SO_2$ with ammonia over coke catalyst which was activated with sulfuric acid was carried out through ultimate analysis DTA, TGA and SEM of catalyst before and after the reaction. Also, the effect of reaction emperature on the reactivity of $SO_2$ with ammonia was determined by means of breakthrough curves with time. The obtained results from this study were summarized as following; Activated cokes were decreased carbon component and increased oxygen and sulfur components in comparison with original cokes. The products over coke catalyst were faced fine crystal of $(NH_4)_2SO_4$, which results in the pressure loss of reacting system. The order of general reactivity in terms of the reaction temperature after breakthrough for $SO_2$ was found to be $150^{\circ}C$ > $200^{\circ}C$ > $100^{\circ}C$. This was related to adsorption amounts of ammonia on the activated cokes.

• Korean Journal of Environmental Agriculture
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• v.6 no.2
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• pp.53-65
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• 1987

The study was performed to investigate the effect of gaseous emissions of sulfur dioxide and hydrogen fluoride on the growth of rice plants under stressed field conditions consisting of 88 industrial plants operating with 285 smoke stacks emitting pollutants. As for the relationship between yields and yield components it is believed that the panicles per hill is the single most important component affecting the rate of yield of the rice plant. Based on the standard partial regression coefficient analysis, panicles per hill has the largest contribution to yield and the average contribution of 54%. Other components such as spikelets per panicle, percent fertility and 1000 grain weight are also contributing factors to yield, although far less so. Fluorine content in the leaf appear to have more negative effect on panicles per hill, percent fertility and subsequent overall yield than does sulfur content in the leaf. It is constantly observed and interesting to note that fluorine and sulfur content in the leaf appears to have no effect on spikelets per panicle and 1000 grain weight. Reduction in yield seems to be affected mainly by panicles per hill which are, in turn, affected more by fluorine content in the leaf as demonstrated by the standard partial coefficient analysis. Regarding the prediction sum of the square of the regression equation, the lowest value was found when nine variables were used for the analysis. The variables taken into consideration were the monthly sulfur and fluorine content in the leaf as well as the monthly percent of leaf damage during the months of June, July and August. A significant correlation is found between the actual and predicted yields by the regression equations selected as a result of a prediction sum of the square analysis.

• Particle and aerosol research
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• v.18 no.3
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• pp.69-77
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• 2022

In order to understand the characteristics of fine particles emitted from coal-fired power plant stacks, it is important to analyze the size distribution and components of particles. In this study, particle size distributions were measured using the ejector-porous tube dilution device and an ELPI system at a stack in a coal-fired power plant. Main elemental components of particles in each size interval were also identified through TEM-EDS analysis for the particles collected in each ELPI stage. Particle size distributions based on number and mass were analyzed with component distributions from 0.006 to 10 ㎛. The highest number concentration was about 0.01 ㎛. The main component of the particles consisted of sulfur, which indicated that sulfate aerosols were generated by gas-to-particle conversion of SO2. In a mass size distribution, a mono-modal distribution with a mode diameter of about 2 ㎛ was shown. For the components of PM1.0 (particles less than 1 ㎛), the abundance order was F > Mg > S > Ca, and however, for the components of PM10 (particles less than 10 ㎛), it was in the order of Fe > S > Ca > Mg. The elemental components by particle size were confirmed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.4
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• pp.348-355
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• 2023

Biodiesel is known as an environmentally friendly neutral fuel, and a policy of obligatory mixing of a certain ratio is implemented on land. In this study, to verify the feasibility of using biodiesel as a ship fuel, component analysis, metal corrosion test, and storage stability test were performed on the mixing ratios of 0 %, 5 %, 10 %, and 20 % of marine diesel and biodiesel. Component analysis evaluated a total of eight factors including density, kinematic viscosity and flash point according to ISO 8217:2017 standards and the reliability of biodiesel through metal corrosion tests and storage stability tests under atmosphere temperature and harsh conditions (60 ℃) for 180 days. Results demonstrate that component analysis satisfied the ISO 8217:2017 standard in all biodiesel mixing ratios. Furthermore, as the biodiesel mixing ratio increased, the kinematic viscosity, density, and acid value increased and the sulfur content decreased. Metal corrosion rarely occurred in the case of carbon steel, iron, aluminum, and nickel, whereas in the case of copper, corrosion occurred under the influence of oxygen-rich biodiesel under the harsh conditions (60 ℃) of 20 % biodiesel mixture. As for storage stability, discoloration, sludge formation, and fuel separation were not visually confirmed.

• Corrosion Science and Technology
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• v.17 no.5
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• pp.231-241
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• 2018

Atmospheric corrosion is generally an electrochemical degradation process of metal. It can be caused by various corrosion factors of atmospheric component, weather, and air pollutants. Moisture, particles of sea salts, and sulfur dioxide are major factors in atmospheric corrosion. Galvanizing coating is one of the most efficient ways to protect iron from corrosion by zinc plating on the surface of the iron. Galvanized steels are being widely used in automobiles, building structures, roofing, and other industrial structures due to their high corrosion resistance compared to bare iron. Atmospheric corrosion of galvanized steel has shown complex corrosion behavior depending on coating process, coating thickness, atmospheric environment, and air pollutants. In addition, different types and kinds of corrosion products can be produced depending on the environment. Lifespan of galvanized steels is also affected by the environment. Therefore, the objective of this study was to determine the corrosion behavior of galvanized steel under atmospheric corrosion at six locations in Korea. When the exposure time was increased, content of zinc from GA surface decreased while contents of iron and oxygen tended to increase. On the other hand, content of iron was constant even after 36 months of exposure of GI.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.E
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• pp.39-43
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• 1999

To help idntify the potential sources of volatile organic sulfur compounds within the continental environment, we have conducted preliminary measurements of dimethylsulfide(DMS) during field campains held from three reference sites. These sampling sites were located within a waste reclamation facility in Won Ju City, Kang Won Province. The results of our measurements showed that DMS levels spanned over 1 to 55 pptv with a mean and 1 standard deviation(1SD) of 12 and 18 pptv(N=13). In a comparison of the data derived from the strongest sources, i.e., oceanic environment, the DMS levels in thre reclamation facility were jpronouncingly low with high day-to-night concentration ratios. It was noted that a significant difference in DMS levels between daytime and nighttime periods was mainly driven by a few exceptional data measured during daytime. Despite limitations of our measurement data in deriving meaningful interpretations of spatiotemporal distributions of DMS in inland facilities, the existence of extraordinary trends, i.e., especially "lower-than-expectedL" DMS values, can be explained in terms of mixed effects of several factors. Most importantly, we can infer that the rates of DMS production and of its destruction in the study site are at or near steady-state condition. Another possibility is that DMS is not adequate enough to explain the generally malordorous environment of reclamation sites, of particular in Won Ju area.n Ju area.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.491-494
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• 2008

The hydrogen fuel and fuel cell which have high energy efficiency and low pollutant emission are getting interest as an alternative energies due to the fossil fuel exhaust, green house effect and atmospheric pollutant problems. The hydrogen gas is very effective as an alternative energy. But, if it is leaked into the air it forms the mixed gas with the air then the danger of the explosion is risen up. So, the secure the safety is mostly important. In this research, to detect the leakage of the hydrogen rapidly, added the odorant materials which don't include the sulfur component into the hydrogen gas and researched on the effect of each odorant on the performance of the fuel cell. As the results, setting the cumulation electric power on the basis and comparing the pure hydrogen, 2,3-Butanedione 5ppm mixed gas 86.1%, 5-Ethylidene-2-Norbornene 17ppm mixed gas 88.2%, Isovaleraldehyde 10ppm mixed gas 74.8%, Ethyl Isobutyrate 2.2ppm mixed gas 93.5% of performance was shown.