• International Journal of Industrial Entomology and Biomaterials
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• 제13권1호
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• pp.45-50
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• 2006

Papers were prepared from cut cocoons and mulberry branches, which are byproducts from sericulture industry. The long filament of silk should be cut into appropriate length in order to prepare paper and this was achieved by chemical method. By a mixture of sodium hydroxide and sodium carbonate solution, the silk filaments were cut into short fibers (less than 1 mm in length). Since the short silk fibers (sSf) could not bind each other by itself, starch and poly(ethylene oxide)(PEO) were added as a bonding agent. When starch and PEO were used in a ratio of 3:7, the silk papers had optimum mechanical properties for paper. Fibers from the skin of mulberry branches (MBF) were added to sSf to enhance the mechanical properties of pure silk paper. Bleaching of MBF was performed with a mixture of hydrogen peroxide and sodium silicate. The mechanical properties were greatly enhanced and the optimum blend ratio of MBF and sSf were 7:3. The mulberry/silk paper has good absorption property against formaldehyde, and therefore, the paper could be applied as a wall paper for preventing the sick house syndrome.

• 유통과학연구
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• 제17권7호
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• pp.65-76
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• 2019

Purpose - The purpose of this study is to investigate economical ventilation effectiveness to reduce hazardous materials exposure and damage of workers by analyzing exposure amount of noxious substances under various ventilation conditions of nail salon for indoor environments. Research design, data, and methodology - This study was carried out with cooperation of Nail shop located in SeongNam city to involve an analysis of the environmental impact indoor air quality, pollutant exposure and economical cost-effectiveness in the nail workplace. The hazardous substances were PM-10(Particulate Matter-10㎛), VOCs(Volatile Organic Compounds) and Formaldehyde, which are the major materials of nail workplace. Results - PM-10 is reduced by about 60% with air cleaner, forced artificial ventilation by 32%, and natural ventilation by about 12%. TVOCs and Formaldehyde showed similar efficiency (80~100%) after natural ventilation and ventilation after 60 minutes. The removal efficiencies of VOCs and formaldehyde were similar to those of natural ventilation and mechanical ventilation system. However, in case of dust, natural ventilation was reduced by artificial ventilation system due to inflow of external dust during natural ventilation. Conclusions - If the pollution degree of outdoor air is not high, air volume is high, and natural ventilation is performed when the air conditioning and heating system is not operated. Even at the end of the work, it keeps operating for 60 minutes to remove the pollutants generated. Results of this analysis demonstrated that the worker environment can be improved by adopting institutional legislation and guidelines for ventilation.

• 청정기술
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• 제22권4호
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• pp.281-285
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• 2016

난분해성 1,4-다이옥산을 분해시키기 위하여 촉매습식과산화반응에 활성적인 Cu wire촉매를 사용하였다. Cu wire 촉매를 사용함으로써 1,4-다이옥산의 완전한 분해가 가능하였으나, 분해된 1,4-다이옥산은 완전 무기화($CO_2$와 $H_2O$로 전환)되지 못하고 중간생성물인 ethylene glycol diformate, oxalic acid, formic acid, formaldehyde, acetaldehyde 등으로 전환되었다. 1,4-다이옥산이 분해되어 없어짐에 따라 formaldehyde와 oxalic acid가 점진적으로 나타나기 시작하여 증가하다가 최고농도를 보인 후 다시 감소하였다. 이들 두 중간체의 최고농도 도달시점에 acetaldehyde의 농도가 급격히 증가하여 최고농도를 보인 후 다시 감소하였다. 이들 세가지 중간물질의 감소와 함께 ethylene glycol diformate, formic acid가 생성되기 시작하여 그 농도가 점진적으로 증가하였다. 이들은 연속적인 과정을 통해 생성되었다. Cu wire 촉매는 반응이 진행되는 동안 활성이 떨어지지 않고 매우 안정적이었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.593-596
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• 2006

The environment-friendly building material, photocatalyst/scoria/loess concrete, was prepared using scoria and loess (which have merits as building materials) and photocatalyst (which has the functions to compose the environmental contaminants and of self cleaning). In order to apply this material as a building material, the compressive and flexible strengths, and water absorptivity (which have been set by Korea Industrial Standard) were measured. In order to know the environment-friendly characteristics of this material, several tests, such as, the tests of emissivity and emission power of far infrared ray and acoustic absorptivity, antibacterial test for Escherichia coli and Pseudomonas aeruginosa, antifungal test for mixed fungal strains, and deodorization test of ammonia were carried out. Moreover, the removal characteristics of NOx, and formaldehyde (HCHO) by photocatalyst/scoria/loess concrete were examined as the following different parameters: the removal characteristics of these contaminants with the substitution ratio and the kind of photocatalyst, light source, UV intensity of sunlight, relative humidity, intial NOx concentration.

• 한국산업융합학회 논문집
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• 제9권2호
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• pp.111-116
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• 2006

This study provides the optimal conditions treating with the coagulation process and the other chemical treatment processes for dyeing wastewater, especially various dyeing complex wastewater. The results are shown as follows: 1. Optimum reaction condition of pH for ferrous sulfate was the range of 9 to 12. And when 3,000ppm(mg/l) of ferrous sulfate was dosed, the maximum $COD_{Mn}$ removal rate was approximately 40%. 2. In case of ferrous chloride and Bittern as coagulants, optimum pH range was 10 to 11. And maximum $COD_{Mn}$ removal rate was approximately 46% to 50% for dose of 2,000ppm(mg/l) to 6,000 ppm. 3. It is confirmed that the activated sludge process following coagulation precipitation method provides better treatment efficiency than the coagulation precipitation method following the activated sludge process. 4. The purpose of this study was to produce CGF (Cyanoguanidineformaldehyde resin) by organic compounds. 5. The complex coagulation agent by this study is the most economical coagulant with Alum(aluminum sulfate) and the removal efficiency is approximately 54% with 1,000ppm(mg/l) of pH range 6 to 7.

• 대한환경공학회지
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• 제28권8호
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• pp.872-877
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• 2006

하루 중 대부분의 시간을 실내에서 보내는 생활패턴으로 인해 실내오염물질의 영향에 대한 관심이 증가하고 있는 실정이다. 이러한 오염물질은 다양한 실내장식물로부터 배출되고 있으며 실내에서 생활하는 시간이 많기 때문에 비록 저농도로 배출된다 하더라도 그 영향은 간과될 수 없을 것이다. 하지만 국내 현실은 실내오염물질에 대한 제도적 기반이 미흡하며 실내오염물질이 발생될 경우 저감 방안에 대한 연구가 부족한 실정이다. 따라서 본 연구는 실내오염물질의 하나인 포름알데히드를 대상으로 광촉매와 인공자외선을 사용하여 실내에서의 저감특성을 파악하였으며 또한 인공자외선의 대안으로 실내에서 형광등을 켜고 생활하는 시간이 많은 점을 고려하여 광촉매/형광등의 실험을 통해 실내 환경정화에 형광등의 잠재적인 사용가능성을 파악하고자 하였다. 실험결과 광촉매량, 반응면적이 증가할수록 포름알데히드의 제거율도 증가하였다. 광원으로 $UV_{254}$ 램프를 사용할 때가 형광등을 사용할 때보다 효과적이었으나 형광등을 사용한 경우도 일정수준의 포름알데히드의 제거가 가능하였으며 반응시간이 증가할수록 제거율은 증가하기 때문에 실내에서 형광등을 켜고 생활하는 시간이 길다는 점을 고려할 때 형광등을 이용할 경우도 실내환경에서 포름알데히드의 제거가 가능할 것으로 판단된다.

• 공업화학
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• 제34권6호
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• pp.612-618
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• 2023

현대 사회는 일상생활 중 80% 이상을 실내에서 생활하고, 생활수준의 향상으로 실내오염물질 노출에 대한 유의가 필요하다. 본 연구에서는 실내오염물질 중 하나인 포름알데히드(HCHO)를 별도의 빛 또는 열 없이 상온에서 제거할 수 있는 액상환원법 기반 Pt/TiO₂ 촉매의 성능 및 반응 특성을 조사하였다. 활성실험을 통해, 동일한 방법으로 제조된 촉매라도 TiO₂ 종류에 따라 약 40~80%의 서로 다른 활성을 나타냄을 확인하였다. XRD, BET, XPS 분석을 통해 지지체의 입사 사이즈, 결정구조, 비표면적 및 O/Ti molar ratio를 조사하였고, 지지체 자체의 물성과 성능 간 상관성은 미미함을 확인하였다. HCHO 산화 반응 경로를 조사하기 위해 일산화탄소를 활용한 In situ DRIFT 분석과 H₂-TPR을 수행하였다. 그 결과, 촉매의 성능이 활성금속의 산화상태 및 흡착종의 흡탈착 특성에 지배받음을 확인할 수 있었다.

• 한국결정성장학회지
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• 제20권3호
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• pp.153-157
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• 2010

본 연구에서는 제강슬래그의 재활용 범위를 확대하기 위하여 제강슬래그를 접촉여재로 활용한 유기화합물의 흡 착성능을 평가하였다. 또한 표면에 미세한 기공을 가지고 있어 흡착여재와 여과필터로 많은 연구가 되어온 규조토를 제강 슬래그와 혼합하여 세라믹 여재를 만들고 유기화합물 흡착 특성을 평가하였다. 유기화합물로는 아세틸알데히드, 포름알데히드, 암모니아 기체를 사용하였으며, 각각 80%, 96%, 85%의 흡착 효율을 나타내었다. 사용된 모든 기체에 대해서 80% 이상의 흡착효율을 나타내어 흡착여제로의 활용 가능성을 확인할 수 있었다.

• 산업기술연구
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• 제28권B호
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• pp.47-52
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• 2008

In this study, GAC adsorption, ozonation and $O_3/GAC$ hybrid processes were investigated for treatment of humic acid. The degradation characteristics and efficiencies of humic acid in each process were evaluated through pH variation, $UV_{254}$ decrease, DOC removal, change of molecular size distribution and by-products formation. DOC removal rate in $O_3/GAC$ hybrid process (80%) was higher than arithmetic sum of ozonation (38%) and GAC adsorption process (19%) by synergism. $UV_{254}$ decrease rate of humic acid was also the highest than any other processes when treated in $O_3/GAC$ hybrid process. Molecular size distribution was not significantly changed in the GAC adsorption process. Main distribution of molecular size of humic acid was converted from 3 k~30 kDa into 0.5 k~3 kDa in ozonation. But the most of large molecular sizes of humic acid converted into small molecules(smaller than 0.5 kDa) in $O_3/GAC$ hybrid process. Quantities of formaldehyde and glyoxal formed in $O_3/GAC$ hybrid process were less than the ones in ozonation.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.98-101
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• 2009

Photo-catalyst technology to the decomposition of formaldehyde, and many are capable of VOC. In this research, effects of screw type photo-catalyst device will announce the experimental results.