• Journal of the Korean Society of Safety
• /
• v.8 no.1
• /
• pp.29-34
• /
• 1993

Two major hazardous gases. SOx and NOx. are emissioned from fossile fuels. SOx has been removed when oil is refined but NOx hasn't. So NOx is very serious problem in air pollution now There are several technologies to remove NOx. e.g. cooling method. scrubbers method. combustion method, polymer membrane method and adsorbent methods. Polymer membrane and adsorbent methods have good economic merit in removal systems of low content hazard gases. Traditional absorbents are porous silicas, aluminas. active carbon and zeolites. But these absorbents act only physisorption which has less removal performance than chemisorption. In this study. polymeric absorbent which has chemisorption as well as physisorption was analyzed about chemical structure and experimented about optimum operation conditions. The results showed that the chemical structure of the polymeric absorbent was expected as polystyrene having -N-CH$_2$COOH absorbent was revealed about 310$m^2$/g. The molar ratio of absored NO to charged NO in absorption experiments was shown 60% of the polymeric absorbent and 45% of zeolite absorbent at 3$0^{\circ}C$.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.9
• /
• pp.3578-3582
• /
• 2010

The nitrogen oxidized substance(NOx) from cars in city is one of serious air-polution problems. In advanced country, the powder or the liquid photocatalystic for asphalt pavement and noise barrier have been used to reduce the air-polution. In this paper, the effect of photocatalystic on asphalt pavement has been evaluated, especially for UV optical science reactions analyzed NOx purification efficiencies of the automobile waste gas. Judging from the limited lab-scale test, the use of the powder or the liquid photocatalystic is one of alternatives to reduce the NOx from automobile.

• Applied Chemistry for Engineering
• /
• v.20 no.5
• /
• pp.522-526
• /
• 2009

The catalytic oxidation of 1,2-dichloribenzene (1,2-DCB) and simultaneous catalytic reduction of nitrogen oxides over the single catalyst has been investigated over various metals (Ru, Mn, Co and Fe) supported on $Al_2O_3$ and $CeO_{2}$. The activity of the different catalysts for catalytic oxidation of 1,2-dichloribenzene depended on the used metal, Ru/Co/$Al_2O_3$, Mn-Fe/CeO2 and Cr/$Al_2O_3$ (commercial catalysts) being the most actives ones. In the catalytic oxidation of chlorobenzene (CB), Ru/Co/$Al_2O_3$ is better than Pt-Pd/$Al_2O_3$, which is the well-known catalyst good for VOC oxidation. Furthermore, it has a good durability on the deactivation by $Cl_2$ and sulfur. For nitrogen oxides (NOx) removal, NOx conversion was 70% at $260^{\circ}C$.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.31 no.3
• /
• pp.93-102
• /
• 2023

This study investigated the possibility of treating heavy metal pollutants existing in the air in addition to simultaneously removing NOx and SOx by injecting oxidizing and reducing agents into a scrubber into a microbubble device to create an eco-friendly method that does not generate secondary pollutants. Lead compound (Pb) was selected as the heavy metal substance in the air to be treated with microbubbles, and the removal efficiency was confirmed. By treating microbubbles by connecting them to a scrubber, it was confirmed that not only NOx and SOx but also heavy metal substances in the air were reduced, cost was reduced, and secondary environmental pollutants were not generated. Through this study, it was possible to simultaneously remove NOx, SOx, and heavy metals at low cost by applying an eco-friendly method, rather than the existing high-cost treatment method such as SCR. If oxidizing agent, reducing agent, and microbubbles are used appropriately, economical and efficient air pollution can be achieved. Since material processing was possible, it is expected to be helpful in the technological development of environmental prevention facilities.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2004.05a
• /
• pp.588-591
• /
• 2004

Generally, $TiO_2$ powders absorb ultraviolet rays and make oxidation/reduction reactions on its surface. Hydroxide radical(OH), a product of photocatalyst reactions, has so strong oxidation/reduction electric potential that it can oxidize noxious gas like VOCs(Volatile Organic Compounds) and NOx. In this study, $TiO_2$ was substituted for exposed concrete to investigate the purifying degree of VOCs(Benzene, Toluene) and NOx. Anatase types of $TiO_2$ were used as photocatalyst. The sun rays and the ultraviolet were used as a light source. Anatase type $TiO_2$ was better than rutile type in purifying performance. The sunray showed the best purifying performance among the light sources. $3\%$ substitution of $TiO_2$ with the sunray was enough to purify VOCs(Benzene, Toluene) and NOx efficiently.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2003.11a
• /
• pp.671-674
• /
• 2003

Generally, $TiO_2$ powders absorb ultraviolet rays and make oxidation/reduction reactions on its surface. Hydroxide radical(OH), a product of photocatalyst reactions, has so strong oxidation/reduction electric potential that it can oxidize noxious gas like NOx. In this study, $TiO_2$ was substituted for cement to investigate the purifying degree of NOx. Rutile and anatase types of $TiO_2$ were used as photocatalyst. The sun rays and the ultraviolet were used as a light source. Anatase type $TiO_2$ was better than rutile type in purifying performance. The sunray showed the best purifying performance among the light sources. 3% substitution of TiO$_2$ with the sunray was enough to purify NOx efficiently.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2003.11a
• /
• pp.141-142
• /
• 2003

최근 자동차 수요증가 및 산업용 보일러 둥 급증하는 추세이며 이로 인한 대도시 대기오염 문제는 위험수위에 도달해 있다. 이러한 산업용 보일러, 화력발전소등 고정배출원과 자동차에서 발생하는 배기가스에는 인체에 유해한 일산화탄소(CO), 질소산화물(NOx), 황산화물(SOx)등이 다량 함유되어 있다. 유독성 가스중 질소산화물(NOx) 저감방법에는 특히 선택적 촉매환원법(Selective Catalytic Reduction, SCR)이 가장 널리 적용되고 있다. SCR법은 촉매하에서 NH$_3$, CO, 탄화수소(메탄, 에탄올, 프로판 등)의 환원제를 사용하여 NOx를 $N_2$로 전환하시키는 기술이다. (중략)

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.1
• /
• pp.900-905
• /
• 2015

DeNOx catalysts composed of Mn, Cu and $TiO_2$ were prepared and tested for $NH_3$-SCR. The performance of each catalyst was studied for the NOx removal efficiency while changing the calcination temperature, reaction time, and oxygen concentration. The hydrogen conversion efficiency of a calcined catalyst was measured at the $H_2$-TPR system. The change in the specific surface area of catalyst according to the calcination temperature was analyzed. As a result, the proper calcination temperature was approximately $300^{\circ}C$. If the calcination temperature is increased to $500^{\circ}C$, the NOx removal efficiency of Mn and Cu constituents is largely decreased at the low temperature range. Oxygen in flue gas is an important parameter in the SCR reaction and optimal oxygen concentration is approximately 8 vol.%.

• Journal of Advanced Marine Engineering and Technology
• /
• v.25 no.1
• /
• pp.57-64
• /
• 2001

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 1999.04a
• /
• pp.225-226
• /
• 1999