식물의 흡수를 통한 공기오염물질 제거는 생육 상태에 따라 그 효과가 달라진다. 실내에서 토양수분의 공급은 식물의 생 육을 위한 기본적인 관리 사항이다. 따라서 본 연구는 토양수 분함량에 따른 생리적 반응이 가스상 공기오염물질인 톨루엔 저감에 미치는 영향을 구명하고, 최적의 생육과 공기 정화 효 과를 위한 적정 토양수분함량을 찾고자 수행하였다. 이를 위 해 스파티필름과 파키라를 사용하여 40일 동안의 평균 토양 수분함량을 25%, 20%, 15%, 10%로 처리한 후 양자수율, 광 합성률, 기공전도도, 증산량 등 생리적 지수와 엽면적당 톨루 엔 저감량을 측정하였다. 그 결과 스파티필름은 토양수분함량 을 20~25%로 관리할 때 생육이 양호하고 최적의 톨루엔 저 감 효과를 얻을 수 있을 것으로 판단되며, 10% 이하 건조에 대한 주의가 요구된다. 반면 파키라는 토양수분함량 20% 이 하 처리구에서 톨루엔 저감량이 증가하였으나 10% 처리구에 서 생장량이 저하될 가능성이 있으므로, 공기 정화와 생육을 위한 최적 토양수분함량은 15~20% 범위이며, 25% 이상으로 장기간 유지하는 것은 과습을 유발할 가능성이 있는 것으로 판단된다.

Volatile organic compounds (VOCs) emitted from industrial gas cause equipment failure and fire accidents due to the rapid flow and concentration changes of VOCs. Therefore, it is crucial to attenuate the concentration of VOCs to ensure a constant emission rate before the control process. This study proposed an encapsulation technique to fabricate calcium- alginate gel beads containing paraffin oil as an effective absorbent. The prepared absorbent was physically characterized, and a column test observed its absorption capacity. When the oil content was 30%, the prepared beads showed the best spherical shape, attaining 96% emulsion stability, 0.014 sphericity factor, 62.7% weight variation ratio, and 4.21 ± 0.06mm diameter. In the column test that was packed with the prepared beads, the toluene absorption capacity was 497.6mg/kg. The net effect of the beads was to attenuate the peaks of toluene concentration, and to make the VOC-laden air stream more receptive for the subsequent treatment unit.

국내외 해상 위험·유해물질(HNS, Hazardous and Noxious Substances) 물동량 증가와 함께 HNS 유출 사고가 빈번히 발생하고 있다. HNS는 전 세계적으로 약 6,000여 종으로 대부분 유독한 성질을 가지므로 이러한 유출 사고 발생은 해양 생태계 파괴를 비롯하여 폭발 및 화재 등으로 인한 인명 및 재산피해를 유발한다. 따라서 해상 HNS 유출 사고를 대비하여 파장에 따른 HNS 분광 라이브러리 구축 및 탐지 알고리즘을 개발해야 한다. 본 연구에서는 프랑스 현지에서 지상 HNS 유출 실험을 진행하였다. 초분광센서 관측을 통해 파장에 따른 톨루엔 라이브러리 스펙트럼을 구축하였으며, 분광혼합 알고리즘을 활용하여 초분광 HNS를 탐지하였다. 전처리 과정으로 주성분 분석을 적용하여 노이즈 제거 및 차원 압축을 수행하였으며, N-FINDR 기법을 통해 영상을 대표하는 톨루엔과 해수의 엔드멤버 스펙트럼을 추출하였다. 스펙트럼 기반의 톨루엔 및 해수의 점유비율을 계산함으로써 모든 픽셀의 HNS 탐지 정확도를 확률로 제시하였다. 최대 탐지 정확도를 가지는 점유비율 선정을 위해 418.15 nm 파장의 복사도 영상과 비교하였으며, 그 결과 약 42%의 비율에 서 99% 이상의 정확도를 나타내었다. 해상 HNS 유출은 높은 위험성으로 인해 사람이 쉽게 접근할 수 없는 한계를 지닌다. 본 HNS 실험과정 및 탐지 결과는 초분광 원격탐사에 기반한 HNS 오염 해역 추정에 도움이 될 것이다.

n-Nonane, 1¸2¸4-trimethylbenzene (124-TMB), toluene, total xylene (TXYL), isopropyl alcohol (IPA), and methyl ethyl alcohol (MEK) are major volatile organic compounds (VOCs) emitted from printing industries. The absorption amount of a single VOC per unit weight of silicone oil was as follows in the order of 189.5 g/kg-silicone oil for n-nonane, 91.7 g/kg-silicone oil for 124-TMB, and 60.1 g/kg-silicone oil for TXYL. Although hydrophobic VOCs were more absorbed in silicone oil than hydrophilic VOCs such as IPA and MEK, IPA and MEK, which had log Kow values of 1 or less, also were absorbed more than 26.0 g/kg-silicone oil. In two and three mixed VOCs of n-nonane, 124-TMB, and toluene, the absorption amount of each in silicon oil was less than that of single a VOC. The total absorption amount of two mixed VOCs ranged from 47.9 g to 138.7 g/kg-silicone oil, and the total absorption amount of three mixed VOCs was 65.8 g/kg-silicone oil. These results suggest that silicone oil is a promising pretreatment solution capable of absorbing high concentrations of VOCs that are intermittently emitted from printing industries. The absorption information of VOCs obtained in this study can be used as the design parameters of a damping device for the pretreatment of VOCs.

To develop flexible adsorbents for compact volatile organic compound (VOC) air purifiers, flexible as-spun zeolite fibers are prepared by an electrospinning method, and then zeolite particles are exposed as active sites for VOC (toluene) adsorption on the surface of the fibers by a thermal surface partial etching process. The breakthrough curves for the adsorption and temperature programmed desorption (TPD) curves of toluene over the flexible zeolite fibers is investigated as a function of the thermal etching temperature by gas chromatography (GC), and the adsorption/desorption characteristics improves with an increase in the thermal surface etching temperature. The effect of acidity on the flexible zeolite fibers for the removal of toluene is investigated as a function of the SiO2/Al2O3 ratios of zeolites. The acidity of the flexible zeolite fibers with different SiO2/Al2O3 ratios is measured by ammonia-temperature-programmed desorption (NH3-TPD), and the adsorption/desorption characteristics are investigated by GC. The results of the toluene adsorption/desorption experiments confirm that a higher SiO2/ Al2O3 ratio of the flexible zeolite fibers creates a better toluene adsorption/desorption performance.

Modified pitch A (MPA) and modified pitch B (MPB) were prepared by oxidative polymerization and thermal polycondensation reaction with refined pitch as the raw material, respectively. The toluene soluble components (TS-1 and TS-2) were obtained by solvent extraction from MPA and MPB, separately. The Flynn-Wall-Ozawa method and Kissinger-Akahira- Sunose method were used to calculate the pyrolysis activation energy of TS. The Satava- Sestak method was used to investigate the pyrolysis kinetic parameters of TS. Moreover, the optical microstructure of the thermal conversion products (TS-1-P and TS-2-P) by calcination shows that TS-1-P has more contents of mosaic structure and lower contents of fine fiber structure than TS-2-P. The research result obtained by a combination of X-ray diffraction and the curve-fitting method revealed that the ratios of ordered carbon crystallite (Ig) in TS-1-P and TS-2-P were 0.3793 and 0.4417, respectively. The distributions of carbon crystallite on TS-1-P and TS-2-P were calculated by Raman spectrum and curve-fitting analysis. They show that the thermal conversion product of TS-2 has a better graphite crystallite structure than TS-1.

Adsorption technology can effectively handle the volatile organic compounds (VOCs) from waste gas. However the adsorption of VOCs at elevated temperature (>30oC) and high humidity conditions results in competitive adsorption between VOCs and the moisture. Furthermore, physical adsorption at an elevated temperature is the cause of degradation in the regeneration process performance. In this study, toluene as waste organic solvent in air at elevated temperature and high humidity was used to measure performance. The effects of the SiO2/Al2O3 ratio of zeolites, the adsorbent material coated on adsorption regenerative rotors, on the adsorption performance of toluene with respect to temperature (30~50oC) and relative humidity (50~90%RH) have been investigated. The adsorption of toluene decreased as relative humidity and adsorption temperature rose. The result shows that Htype ZSM5 (SiO2/Al2O3=100) zeolite exhibited the highest adsorption capacity for toluene at elevated temperature and humidity conditions. The physical and chemical adsorption of toluene on acid sites of zeolite were confirmed by this study.

Activated carbon (AC) was used as an adsorbent for removal of volatile organic compounds (VOCs). The purpose of this research is to study the effect of acidic treatments of activated carbons on toluene adsorption. The physicalchemical properties of activated carbons were characterized by N2 adsorption-desorption isotherms, temperatureprogrammed desorption (TPD). The adsorption amount of toluene showed an order of S-AC-10% > S-AC-5% > A-AC > AC. It was also found that acid solution pH showed a significant influence on adsorption of toluene. Because strong acid treatment increased the surface oxygen group species of activated carbon, and this group was observed to be the carboxyl acid group by TPD analysis. In addition, the toluene adsorption amount by activated carbon increased with the concentration of H2SO4 solution from 5% to 10%. Adsorption ability of activated carbon surface with toluene is thought to increase as the amount of oxygen group on AC increases.

The efficiency of using 7 indoor plants, which were Chrysalidocarpus lutescens, Ficus robusta, Sansevienria trifasciata, Rhapis excelsa, Scindapusus aureus, Anthurium andraeanum and Pachira aquatica, for B·T·E (Benzene, Toluene, Ethylbenzene) removal were assessed at 1200 Lux light intensity in airtight chambers (1.27 m3). Rhapis excelsa, Chrysalidocarpus lutescens and Ficus robusta were among the most effective plants, completely removing for B·T·E within 38 hours, wherease Scindapusus aureus and Sansevienria trifasciata were the lowest in terms of removal efficiency. But when the removal efficiency was measured per unit leaf area (μg·m−3·−2), it was found that Scindapusus aureus, Anthurium andraeanum and Sansevienria trifasciata removed higher amount than Rhapis excelsa, Chrysalidocarpus lutescens and Ficus robusta. Plants with wide leaves and a big leaf area including Rhapis excelsa and Chrysalidocarpus lutescens showed higher removal efficiencies of B·T·E than those with smaller leaves such as Scindapusus aureus. Among the plants tested over 120 hours, the species that emitted the highest levels of CO2, involved with photosynthesis and respiration in plants, Pachira aquatica (11,560 ppm) was emitting 10 times more CO2 than Scindapusus aureus (1,260 ppm).

The adsorption/desorption characteristics of toluene vapors filled with activated carbon(AC) were studied. Adsorption performance of AC was investigated according to flow rate, moisture content, and other factors. The breakthrough time was shortened as the flow rate and moisture content increased. The AC loaded with toluene was regenerated by programmed heating and pressure. AC was regenerated well, as the conditions of heating temperature(80oC) and pressure(100 torr) were appropriate. Toluene is more easily removed at low temperature than through thermal desorption methods. The test of AC regeneration was carried out three times.

This study was performed to obtain high conversion efficiency of C7H8 using non-thermal plasma and metal-supported catalyst. Adsorption-desorption characteristics of toluene was performed using 4A type (Zeolite) filled in a concentration reactor. Through this test, it was found that the concentration reactor has 0.020 g/g of adsorption capacity (at ambient temperature and pressure) and 3,600 ppm of desorption property at 150℃ (with in 20 min). In case of developed catalyst, toluene decomposition rate of Pd-AO (Pd coated catalyst) was better than Pd/Cu-AO and Pd/Ag-AO (Pd/Ag composite metal catalyst). Developed non-thermal plasma system was obtained flame amplification effect using injection process of desorbed tolune, and 98% of removal efficiency.

Toluene is one of the typical index substances of environmental odor. In this study the vaporized toluene was decomposed by peroxide ions which are formed from a newly developed low-temperature plasma generator. The number of ions composed mostly of negative was controlled by electric voltage below 3.0 kV, which could produce the minimum super oxide and ozone. The test plasma generator produced 84.1~560×103 ions/㎤ depending on air velocity. It was found that toluene decomposition rate corresponded proportionally to the plasma intensity. The efficiency with the plasma output, 3.0 kV was 97.5% in a batch process.

According to a recent government study, development and distribution of functional building materials are increasing in Korea.
In this study, we evaluated reduction performance of formaldehyde and toluene by sorptive building materials using small-scale chamber(20L) test method for 7 days.
According to the results of this study, 18 building materials showed that the effects of formaldehyde reduction among the 23 building materials. And the number of the building materials with respect to its ability to reduce the concentration of toluene was relatively small.
The mean sorption rate and total amount of sorption for formaldehyde were 36.8% and 1,525.4㎍/㎡, respectively. The sorption rate and total amount of sorption for formaldehyde were in the range 1.5∼78.4% and 87.5∼3,086.0㎍/㎡, respectively.
And the mean sorption rate and total amount of sorption for toluene were 11.6% and 1,054.4㎍/㎡, respectively. The sorption rate and total amount of sorption of toluene were in the range 0.1∼62.4% and 29.6∼6,764.0㎍/㎡, respectively.
In most cases, the performance of the building materials with respect to its ability to reduce the concentration of pollutants has steadily decreased within 7 days.

본 연구는 VOC 배출원 중 도장, 인쇄 공정에서 주요 발생물질인 톨루엔을 저온 분해할 수 있는 귀금속 팔라듐촉매 개발에 목적을 두고 있다. 팔라듐은 톨루엔 제거에서 활성이 우수하지만 비용이 높다. 따라서 실용성의 방안으로 Pd 담지량의 최소화 비율(0.1~1.0wt%)로 제조한 촉매의 활성을 측정하였다. 그 결과 1.0wt% Pd(R) 촉매가 모든 조건에서 가장 높은 활성을 나타내었다. 이는 SEM 촬영과 XRD 분석을 통해 촉매 제조과정에서 Pd의 담지량 및 소성 분위기에 따른 분산 형태와 연관이 있는 것으로 사료된다.

매연 생성에 대하여 톨루엔의 영향을 알아보기 위하여 순수에틸렌 대향류 확산화염에 톨루엔을 소량 혼합하여 수치해석을 수행하였다. 톨루엔(C7H8)의 혼합 비율은 3%, 5%, 10%, 및 20%로 하였다. 계산에는 CHEMKIN III 기반의 Senkin 코드와 oppdif 코드를 이용하여 0-D 계산과 1-D 계산을 수행하였다. 0-D의 Senkin 계산에서는 톨루엔의 혼합율이 증가할수록 메틸라디칼의 농도는 증가하고 이에 따른 벤젠의 농도도 증가하였다. 이는 순수 에틸렌 화염에 톨루엔을 혼합할 경우 더 많은 매연이 생성될 것이라는 걸 의미한다. oppdif 코드에 의한 1-D 계산에서는 10% 톨루엔 반응식으로부터는 H 라디칼의 생성율이 결정적인 역할을 한다는 것을 알 수 있었다. 위 결과들로부터 확산화염 내 매연 생성에 있어 메틸라디칼, 벤젠과 H 라디칼이 중요한 역할을 한다는 것을 알 수 있었다.

A novel experimental set-up allowing quantitative determination of the adsorption capacity of gas molecules on a surface under high-vacuum conditions is introduced. Using this system, the toluene adsorption capacities of various carbon nanostructures were determined. We found that for a give surface area, the adsorption capacities of toluene of multi-walled carbon nanotubes and nanodiamonds were higher than that of activated carbon, which is widely used as an adsorbent of volatile organic compounds. The adsorption of toluene was reversible at room temperature.

nanopowders with anatase structure were firstly prepared by controlling the pH value of a precursor solution without any heat-treatment at room temperature. The prepared nanopowders were hydrothermally treated in 10M NaOH solution at . Then, the samples were washed in DI water or 0.1M HCl. The nanotubes were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The gas sensitivity of nanotubes for toluene gas was also investigated. The results show that nanotubes can be prepared by hydrothermal treatment. The morphology of nanotubes prepared by 0.1M HCl washing is destroyed to some extent. nanotubes with DI water washing show better sensitivity than that with 0.1M HCl washing.

In this study, toluene catalytic oxidation was investigated using various metal components (Cu, Ce, Ni, La and Zr) supported on Used FCC zeolite for the application of the waste recycling and odor reduction. Among the metals, 5 wt% Cu/zeolite showed the best catalytic activity. 100 % conversion was achieved at 300℃ which was 50℃ lower than that of other metal components. As increasing the amount of doped Cu, the CuO was formed and the surface area and pore size were decreased. By the reduction treatment before toluene oxidation, the catalytic activity of the oxidation below 250℃ was improved. No decrease of conversion was observed during the continuos reaction at 300℃ for 48 h.

the less-reported gaseous studies have primarily dealt with chemical process stream concentrations than indoor air quality (IAQ) concentration levels. Accordingly, the current study was conducted to establish the feasibility of applying visible-light-induced TiO₂ doped with sulfur (S) element to cleanse toluene and ehtyl benzene at IAQ levels. The S-doped TiO₂ was prepared by applying two popular processes and two well-known methods. For both target compounds, the two coating methods exhibited different photocatalytic oxidation (PCO) efficiency. Similarly, the two S-doping processes showed different PCO efficiency. These results indicate that the coating method and doping process are important parameters which can influence PCO efficiency. Meanwhile, it was found that the PCO efficiency of ethyl benzene was higher than that of toluene. In addition, the degradation efficiency of the target compounds increased as the relative humidity (RH) decreased. The PCO efficiency varied from 44% to 74% for toluene and from 68% to 95%, as the RH decreased. Consequently, it is suggested that with appropriate RH conditions, the visible-light-assisted photocatalytic systems can also become an important tool for improving IAQ.

수질오염을 일으키는 휘발성 유기 화합물(Volatile Organic Compounds; VOCs)의 대표적인 종류의 하나인 저농도의 톨루엔이 함유된 수용액을 소수성 폴리이미드공중합체막을 이용한 투과증발법으로 분리하였다. 이를 위해 폴리실록산디아민(SIDA)과 과불소알킬기를 가진 방향족 디아민(PFDAB)의 비율에 따른 폴리이미드 공중합체 막을 제조하였다. 막제조에 사용된 SIDA/PFDAB 비에 따른 선택투과특성의 변화를 살펴보았다. 얻어진 투과특성을 용해확산이론으로 해석하기 위해 톨루엔 수용액의 수착특성을 조사하였으며 이를 토대로 확산도 특성을 조사하였다. 그 결과 실록산 고분자에 대한 톨루엔의 친화도의 증가로 SIDA의 함량이 많을수록 막 내의 톨루엔에 대한 용해도 및 톨루엔/물의 수착선택도가 커졌으며, 자유부피가 큰 실록산의 함량증가로 인해 톨루엔의 확산계수, 확산선택도가 증가하는 것을 확인하였다. 이러한 결과로 SIDA의 함량이 증가함에 따라 톨루엔에 대한 투과도는 0.005 kg/m2h에서 0.049 kg/m2h로 증가하고, 톨루엔/물의 투과선택도는 9에서 6380로 증가함을 관찰하였다.