DBM(DiButyl Maleate)을 포함한 잠재적 디젤첨가제 생분해특성

장순웅(Chang Soonwoong) 한국지반환경공학회 2010 한국지반환경공학회논문집 Vol.11 No.8

본 연구에서는 디젤오염토양에서 활성화된 토착미생물을 이용한 DBM을 포한한 디젤첨가제와 유사한 물리화학적 특성을 갖는 가솔린첨가제를 대상으로 호기성 조건에서의 생분해성 평가를 수행하였다. Toluene, Ethanol 등이 가장 높은 활성도를 보였고, 일차분해상수는 0.11∼0.3 day?¹의 범위를 보여주었다. 반면에, 가솔린첨가제인 MTBE는 낮은 분해 특성을 보여주어 토양미생물에 제한적인 분해기질로 나타났다. 이와 더불어, DBM과 TGME를 대상으로 초기농도의 증가에 따른 분해 특성을 조사한 결과 초기농도 증가에 따라 분해속도는 감소하는 것으로 관찰되었다. 또한 DBM과 TGME의 생분해도를 평가하기 위한 방안으로 디젤첨가제의 저감과 동시에 CO₂ 생성 모니터링과 조류에 의한 독성 변화를 조사한 결과, 디젤첨가제의 농도 감소와 더불어 CO₂ 생성량의 증가는 DBM과 TGME의 무기화를 간접적으로 보여주고 있으나, DBM과 TGME이 완전히 분해되었음에도 불구하고 조류에 의한 잔류독성이 남아있는 결과는 완전 무기화가 일어나지 않고 중간 부산물이 생성된 것으로 추정된다. 그럼에도 불구하고, DBM과 TGME를 포한한 디젤첨가제에 대한 생물학적 분해 연구는 국내에서 처음 보여주는 결과로 국내 유류오염지역의 생물학적 자연저감의 원리를 적용한 현장적용 타당성을 좀 더 높여주는 결과라고 판단된다. In this study, we have evaluated biodegradability of diesel-oxygenates including DBM and gasoline-oxygenates having similar physio-chemical properties using indigenous aerobic microorganisms from a diesel-contaminated soil. Toluene and Ethanol have shown higher biological activity and the first-order degradation rate constants ranged around 0.11∼0.3 day?¹. However, MTBE, gasoline-oxygenate has shown as a limited substrate. Moreover, As increased initial concentrations of DBM and TGME, degradation rates of those were decreased relatively. As a strategy to evaluate biodegradability of DBM and TGME, reduction of dieseloxygenates, CO₂ production and toxicity by algae were monitored. This results indicated possible mineralization of diesel-oxygenates, But we could predict that residual byproduct produced even though complete consumption of diesel-oxygenates were observed if algal toxicity variation considered. In conclusion, it is the first report that diesel-oxygenates including DBM could be biodegraded effectively by indigenous soil microorganisms and this result increased the possibility of bioremediation technology to apply into oil-contaminated sites.

전자빔 공정을 적용한 Triclosan의 제거특성 및 독성평가

장태범(Chang Taebum),장순웅(Chang Soonwoong),이시진(Lee Sijin),조일형(Cho Ilhyoung) 한국지반환경공학회 2012 한국지반환경공학회논문집 Vol.13 No.3

본 연구의 목표는 전자빔 공정을 적용하여 Triclosan의 제거효율 및 독성평가를 하는 것이다. 이 실험에서는 전자빔 선량과 Triclosan의 초기 농도에 따른 저감 효율 및 스캐벤저 가스에 따른 무기화의 정도를 알아보았다. 또한 녹조류 중 하나인 Pseudokirohneriella Subcapitata를 이용하여 생물독성과 위해성 평가를 통한 독성저감기술을 시험하였다. 그 결과 Triclosan은 전자빔 조사량이 증가할수록 분해 효율이 향상되었고, 라디칼 스캐벤저 가스에 의한 TOC 제거는 N₂O나 O₂를 용해시켰을 때 효율이 증가된 것으로 나타났다. 4일(96hrs) 후 독성평가 결과 전자빔 조사 강도의 증가에 따라 독성 영향이 저감되는 것을 알 수 있었다. The abjective of this study was to study the degradation behavior and acute toxicity assessment of Triclosan and acute toxicity under E-beam irradiation. The experiments were conducted to investigate the efficts of the degradation efficiency in the initial concentration of Triclosan and the irradiation capacity of E-beam and the degree of mineralization based on a change of scavenger gas. The biological toxicity test by using on green algae, Pseudokirchneriella Subcapitata was conducted to lead the reducing toxicity. Degradation efficiency of Triclosan was improved when E-beam irradiation intensity was higher. Additionally, the % of TOC removal in each Radical scavenger gas was increased as the follows orders: N₂O>O₂>N₂, The toxicity test showed that the toxicity effect after 4 days(96hrs) was decreased by increase of E-beam irradiation intensity.

전자빔 공정을 적용한 1,4-dioxane의 제거특성 및 독성평가

황혜영(Hwang Haeyoung),장순웅(Chang Soonwoong) 한국지반환경공학회 2011 한국지반환경공학회논문집 Vol.12 No.2

본 연구의 목표는 전자빔 공정을 적용하여 1,4-dioxane의 제거효율 및 독성평가를 하는 것이다. 이 실험에서는 전자빔 선량과 1,4-dioxane의 초기 농도에 따른 저감 효율 및 scavenger gas에 따른 무기화의 정도를 알아보았다. 또한 녹조류 중 하나인 Pseudokirohneriella Subcapitata를 이용하여 생물독성과 위해성 평가를 통한 독성저감기술을 확립하였다. 그 결과 1,4-dioxane은 전자빔 조사량이 증가할수록 분해 효율이 향상되었고, Radical Scavenger gas에 의한 TOC 제거는 N₂O나 O₂를 용해시켰을 때 효율이 증가되었다. 4일(96hrs) 후 독성평가 결과 전자빔 조사 강도의 증가에 따라 독성 영향이 저감되는 것을 알 수 있었다. The aim of this study was 1,4-dioxane's degradation efficiency and toxicity test applying E-beam. The experiments were shows that the degradation efficiency in the initial concentration of 1,4-dioxane and the irradiation capacity of E-beam and the degree of mineralization based on a change of scavenger gas. The biological toxicity test by using on of green algae, Pseudokirchneriella Subcapitata was conducted to lead the reducing toxicity. Degradation efficiency of 1,4-dioxane was improved when E-beam irradiation intensity was higher and the efficiency of TOC removal using Radical scavenger gas was increased by N₂O, O₂ and N₂ in order. In 4 days(96hrs), toxicity test results indicated that toxicity effect was decreased by increase of E-beam irradiation intensity.

산림특성에 따른 강우유출수 유출특성 및 상관관계 분석

정우진 ( Woojin Chung ),장순웅 ( Soonwoong Chang ) 한국환경과학회 2016 한국환경과학회지 Vol.25 No.7

Environmental policy implementation has been strengthened to protect the source waters in Korea and to improve their water quality. Increasing of non-point source caused water quality problem continuously. Research on runoff from forests, which occupy over 65% of the land in korea, is insufficient, and studies on the characteristics and influences of storm runoff are necessary. In this study, we chose to compare the effects of land use in the form of two types of forest distribution and then gathered data on storm characteristics and runoff properties during rainfall events in these areas. Furthermore, the significance and influences of the discharges were analyzed through correlation analysis, and multilateral runoff characteristics were examined by deducing a formula through COD(Mn) and TOC regression analysis. At two forest points, for which the basin areas differed from each other, flow changed according to storm quantity and intensity. The peak discharge at point A, where the basin area was big, was high, whereas water-quality fundamental items (BOD, COD(Mn), and SS) and TOC density were high at point B where the slope and storm intensity were high. Effects of dissolved organic matter were determined through correlation analysis, and the regression formulas for COD(Mn) and TOC were deduced by regression analysis. It is expected that the data from this study could be useful as basic information in establishing forest management measures.

광분해반응을 통한 MTBE 제거에 대한 통계적 최적화 연구

천석영(Chun Sukyoung),장순웅(Chang Soonwoong) 한국지반환경공학회 2011 한국지반환경공학회논문집 Vol.12 No.9

본 연구는 UV와 H₂O₂를 통한 광분해 반응기에서의 Methyl Tert Butyl Ether(MTBE) 제거에 대해 조사하였다. 이 공정은 일반적으로 UV의 존재 하에 수용액 상에 생성되는 OH 라디칼을 요구하며, 이 라디칼들은 MTBE 분자를 공격하여 최종적으로 파괴하거나 무해한 단순 화합물로 전환시킨다. 반응들은 조사강도, MTBE 초기농도와 H₂O₂/MTBE비의 독립변수를 수학적으로 표현하였고, 반응표면법(Response Surface Methodology; RSM)을 사용하여 모델화하였다. 이 실험들은 Box-Behnken Design(BBD)를 통한 15개의 실험을 포함하여 실시하였다. ANOVA의 회귀분석 항은 유의한 p-value(p<0.05)와 높은 결정계수(R²=94.60%)를 나타내어 2차 회귀모델의 예측이 적절한 것으로 나타났다. 그리고 반응에 대한 정준분석을 통해 예측된 Y에 대한 최적 반응과 최대반응의 예측된 능선을 통해 최적조건은 각각 조사강도인 x₁=25.75W, MTBE 초기농도의 x₂=7.69㎎/ℓ 와 H₂O₂/MTBE비인 x₃=11.04로 관찰되었다. 본 연구는 RSM이 MTBE 제거의 최대화와 운전조건의 최적화에 적용하기에 알맞은 것으로 나타났다. This study investigate the use of ultraviolet(UV) light with hydrogen peroxide(H₂O₂) for Methyl Tert Butyl Ether(MTBE) degradation in photolysis reactor. The process in general demands the generation of OH radicals in solution at the presence of UV light. These radicals can then attack the MTBE molecule and it is finally destroyed or converted into a simple harmless compound. The MTBE removal by photolysis were mathematically described as the independent variables such as irradiation intensity, initial concentration of MTBE and H₂O₂/MTBE ratio, and these were modeled by the use of response surface methodology(RSM). These experiments were carried out as a Box-Behnken Design(BBD) consisting of 15 experiments. Regression analysis term of Analysis of Variance(ANOVA) shows significantly p-value(p<0.05) and high coefficients for determination values(R²=94.60%) that allow satisfactory prediction of second-order regression model. And Canonical analysis yields the stationery point for response, with the estimate ridge of maximum responses and optimal conditions for Y(MTBE removal efficiency, %) are x₁=25.75 W of irradiation intensity, x₂=7.69 ㎎/ℓ of MTBE concentration and x₃=11.04 of H₂O₂/MTBE molecular ratio, respectively. This study clearly shows that RSM is available tool for optimizing the operating conditions to maximize MTBE removal.

광분해반응을 통한 MTBE 분해 시 음이온 영향의 통계적 분석

천석영(Chun, Sukyoung),장순웅(Chang, Soonwoong) 한국지반환경공학회 2011 한국지반환경공학회논문집 Vol.12 No.10

이 연구는 Methyl tert Btyl Ether(MTBE)의 광촉매반응을 통한 제거시에 다양한 음이온(Cl?, NO₃?, HCO₃?)들의 영향을 통계적 방법을 사용하여 조사하였다. 이 공정은 일반적으로 UV의 존재 하에 수용액상에 생성되는 Hydroxyl radicals(OH라디칼)의 생성에 기초하며, 이러한 라디칼들의 생성은 수용액 상의 무기 음이온들이 OH라디칼과의 반응에 의해 광분해를 방해한다. 이런 무기 음이온들의 영향은 반응표면법(RSM)의 한 종류인 혼합물분석(Mixture analysis)를 통해 Cl?, NO₃?와 HCO₃?의 독립변수들을 수학적으로 표현하였다. 분산분석(Analysis of variance; ANOVA)의 회귀분석항은 유의한 p값(p<0.0001)과 높은 결정계수(R²=99.28%, R²adj=98.91%)를 나타냈다. 그리고 등고선도(Contour plot)와 반응표면도(Response surface plot)는 UV/H₂O₂ 공정에 기초한 MTBE광분해에 대한 무기 이온들의 영향을 나타내었다. 이 연구의 결과는 MTBE의 광분해에 대해 Cl?와 HCO₃? 이온이 OH라디칼의 생성을 방해하는 것으로 나타났고 이 두 인자에 의한 상호작용이 관찰되었다. This study investigated the effects of various inorganic anions(Cl?, NO₃?, HCO₃?) on the Methyl tert Butyl Ether(MTBE) degradation by photocatalysis using statistical method. Generally, this process in general demands the generation of hydroxyl radicals(OH radical) in solution in the presence of UV light. The generation of radicals were affected by inorganic anions in solution that inhibited the photodegradation by their trapping hydroxyl radicals. The effects of inorganic anions were mathematically described as the independent variables such as Cl?, NO₃?, and HCO₃?, and these were designed by mixture analysis that was one of the response surface methodology(RSM). Regression analysis on ANOVA showed significant p-value(p<0.0001) and high coefficients for determination value(R²=99.28%, R²adj=98.91%). Contour and response surface plots showed that the effects of inorganic anions for MTBE photodegradation based on UV/H₂O₂ process. In the result, Cl? and HCO₃? inhibited the photodegradation of the MTBE by their trapping hydroxyl radicals, and the interaction by these two factors was observed.

HAP/TiO<SUB>2</SUB> 여재를 이용한 Reactive Black 5(RB5)의 광촉매 반응과 흡착

천석영(Chun. Sukyoung),장순웅(Chang, Soonwoong) 한국지반환경공학회 2011 한국지반환경공학회논문집 Vol.12 No.11

본 연구는 Hydroxyapatite(HAP)/TiO2 여재에 의한 Reactive Black 5(RB5)의 흡착과 광촉매 반응을 조사하였다. RB5에 대한 TiO2, HAP와 TiO2/HAP의 흡착은 연속적인 회분식 실험을 통해 조사하였다. 흡착평형에 따른 결과를 나타내었으며 Langmuir와 Freundlich isotherm model을 사용하여 적용성을 조사하였다. TiO2, HAP와 TiO2/HAP 흡착제별 흡착평형 결과는 Langmuir isotherm model에 적합하였으며 최대흡착량(Qmax)의 값은 각각 단일 TiO2는 5.28mg/g, 단일 HAP는 12.45mg/g, TiO2/HAP는 9.03mg/g으로 나타났다. 흡착과 광촉매 반응에 대한 kinetic model들은 유사 1차 반응을 통해 분석하였으며, 이들 model에 따르면 TiO2/HAP에 의한 RB5 제거는 광촉매 반응과 흡착반응의 상호작용의 영향을 받는 것으로 나타났다. This study investigated on the adsorption and photocatalysis of Reactive Black 5(RB5) by the hydroxyapatite(HAP)/ Titanium dioxide(TiO2) media. The adsorption of RB5 on TiO2, HAP and TiO2/HAP was investigated during a series of batch adsorption experiments. The amounts adsorbed at equilibrium were measured. Langmuir and Freundlich isotherm models were tested for their applicability. The result of equilibrium studies of TiO2, HAP and TiO2/HAP adsorbent were found to follow Langmuir isotherm model. The adsorbed amounts(Qmax) were found to be 5.28mg/g on single TiO2, 12.45mg/g on single HAP and 9.03mg/g on TiO2/HAP, respectively. The experimental data were analysed using the pseudo-first-order adsorption and photocatalysis kinetic models. According to these models, RB5 degradation by TiO2/HAP was affected by interaction effect of photocatalysis and adsorption.

혼합물분석을 통해 최적화된 TiO₂/HAP/Ge 촉매를 이용한 Lincomycin 제거특성 연구

김동우(Dongwoo Kim),장순웅(Soonwoong Chang) 한국지반환경공학회 2014 한국지반환경공학회논문집 Vol.15 No.1

연구에서는 UV-A 조사를 통해 titanium dioxide(TiO₂), hydroxyapatite(HAP)와 germanium(Ge)의 다양한 복합촉매를 통한 항생제(lincomycin, LM)의 광촉매 제거를 조사하였다. 우선, 다양한 복합촉매의 향상된 광촉매능을 비교하였고, 도출된 제거효율은 TiO₂/HAP/Ge > TiO₂/Ge > TiO₂/HAP 순으로 관찰되었다. TiO₂/HAP/Ge의 조성은 반응표면법의 하나인 혼합물분석(mixture analysis)에 기초하여 통계적 방안이 수행되었다. 각 인자별 6개의 조건을 포함하도록 설정한 독립변수 TiO₂(X₁), HAP(X₂)와 Ge(X₃)의 LM(Y₁)과 TOC(Y₂) 제거에 대한 영향을 살펴보았다. 분산분석(ANOVA)의 회귀분석항은 유의한 p값(p<0.05)과 높은 결정계수 값(R2 of Y₁=99.28% and R<SUP>2</SUP> of Y₂=98.91%)을 나타냈다. 등고선도와 반응곡선을 통해 UV-A 조사조건에서 TiO₂/HAP/Ge 조성에 따른 LM의 제거를 나타냈다. TOC(Y₂) 제거를 기준으로 도출된 최적조성비는 코드화 값으로 X₁=0.6913, X₂=0.2313과 X₃=0.0756으로 나타났다. 실제 적용에 따른 비교 실험 결과는 LM과 TOC의 평균제거율이 각각 99.2%와 49.3%로 나타나 모델의 예측과 잘 부합하였다. In this study, it was found that determined the photocatalytic degradation of antibiotics (lincomycin, LM) with various catalyst composite of titanium dioxide (TiO₂), hydroxyapatite (HAP) and germanium (Ge) under UV-A irradiation. At first, various type of complex catalysts were investigated to compare the enhanced photocatalytic potential. It was observed that in order to obtain the removal efficiencies were TiO₂/HAP/Ge > TiO₂/Ge > TiO₂/HAP. The composition of TiO₂/HAP/Ge using a statistical approach based on mixture analysis design, one of response surface method was investigated. The independent variables of TiO₂ (X₁), HAP (X₂) and Ge (X₃) which consisted of 6 condition in each variables was set up to determine the effects on LM (Y₁) and TOC (Y₂) degradation. Regression analysis on analysis of variance (ANOVA) showed significant p-value (p < 0.05) and high coefficients for determination value (R<SUP>2</SUP> of Y₁=99.28% and R<SUP>2</SUP> of Y₂=98.91%). Contour plot and response curve showed that the effects of TiO2/HAP/Ge composition for LM degradation under UV-A irradiation. And the estimated optimal composition for TOC removal (Y₂) were X₁=0.6913, X₂=0.2313 and X₃=0.0756 by coded value. By comparison with actual applications, the experimental results were found to be in good agreement with the model’s predictions, with mean results for LM and TOC removal of 99.2% and 49.3%, respectively.

농업 부산물의 이화학적 특성 분석 및 농업 부산물 활용 가축분 혼합 퇴비화

방동규(Donggyu Bang),장순웅(Soonwoong Chang),김민규(Mingyu Kim),심재홍(JaeHong Shim),정우진(Woojin Chung) 한국토양비료학회 2023 한국토양비료학회 학술발표회 초록집 Vol.2023 No.10

A Study of the Correlation Between the Physical Characteristics and Efficiency of TiO₂ Photocatalyst Prepared with the Sol—Gel Method

Chung, Woojin,Kim, Sungsu,Chang, Soonwoong American Scientific Publishers 2016 Journal of Nanoscience and Nanotechnology Vol.16 No.10

<P>TiO2 photocatalysts were prepared by the sol-gel method using different sintering temperatures and hydrolysis pH conditions, and were characterized using scanning electron microscopy, X-ray diffraction, and surface area analysis. The photocatalytic efficiencies of the prepared TiO2 samples were evaluated by their ability to promote the achromatization of the dye reactive orange 16 in a batch test reactor under UV irradiation. In addition, the correlation between the rate constant of the achromatization and the particle size and surface area of the catalysts was investigated. The efficiency appeared to be highest for particles with a size of 10-14 nm and a specific surface area of 70-80 m(2)g(-1). From these results, it was concluded that the photocatalytic efficiency is dependent on the particle size, crystallinity, and specific surface area of the catalyst.</P>