반응표면분석법을 이용한 폐감귤박 활성탄에 의한 수중의 2,4-Dichlorophenol 흡착특성 해석

이창한,감상규,이민규,Lee, Chang-Han,Kam, Sang-Kyu,Lee, Min-Gyu 한국화학공학회 2017 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.55 No.5

폐감귤박으로 제조한 활성탄(WCAC)에 의한 2,4-디클로로페놀(2,4-DCP) 흡착에서 온도, 초기농도, 접촉시간 및 흡착제 투여량과 같은 운전변수의 영향을 조사하기 위해 회분식 실험 및 반응표면분석법(Response Surface Methodology: RSM)을 적용하였다. 2,4-DCP 흡착부터 도출된 회귀식은 반응변수의 함수로 나타낼 수 있었다. 이 모델의 적합성은 응답에 대한 실험값과 예측값 간의 상관관계에 의해 평가되었다. $R^2$ 값은 0.9921로서 높은 상관성을 가지며, 회귀 모델에 의해 대부분의 데이터 변동을 설명할 수 있었다. 독립변수 및 그 상호작용의 유의성은 분산분석(ANOVA)과 t-검정 통계 기법으로 평가하였다. 이들 결과는 사용된 모델이 응답변수를 유의미하게 잘 부합되며, 응답과 독립 변수 간의 관계를 적합하게 잘 설명한다는 것을 보여 주었다. 흡착 속도 및 등온 실험결과는 각각 유사 2차 속도식 및 Langmuir 등온 모델에 의해 잘 설명될 수 있었다. Langmuir 등온 모델로부터 계산된 WCAC에 의한 2,4-DCP의 최대 흡착량은 345.49 mg/g이었다. 흡착과정에서 막확산과 입자내부확산이 동시에 일어나는 것을 흡착 메커니즘 연구로부터 확인하였다. 열역학적 파라미터는 WCAC에서 2,4-DCP의 흡착 반응이 흡열반응이고 자발적인 과정임을 나타내었다. The batch experiments by response surface methodology (RSM) have been applied to investigate the influences of operating parameters such as temperature, initial concentration, contact time and adsorbent dosage on 2,4-dichlorophenol (2,4-DCP) adsorption with an activated carbon prepared from waste citrus peel (WCAC). Regression equation formulated for the 2,4-DCP adsorption was represented as a function of response variables. Adequacy of the model was tested by the correlation between experimental and predicted values of the response. A fairly high value of $R^2$ (0.9921) indicated that most of the data variation was explained by the regression model. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. These results showed that the model used to fit response variables was significant and adequate to represent the relationship between the response and the independent variables. The kinetics and isotherm experiment data can be well described with the pseudo-second order model and the Langmuir isotherm model, respectively. The maximum adsorption capacity of 2,4-DCP on WCAC calculated from the Langmuir isotherm model was 345.49 mg/g. The rate controlling mechanism study revealed that film diffusion and intraparticle diffusion were simultaneously occurring during the adsorption process. The thermodynamic parameters indicated that the adsorption reaction of 2,4-DCP on WCAC was an endothermic and spontaneous process.

Preparation of titania-containing photocatalysts from metallurgical slag waste and photodegradation of 2,4-dichlorophenol

Hong Liu,S Vigneswaran,Tao Xia,H.K. Shon 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.3

A low cost, high performance titania-containing metallurgical slag photocatalysts (TCMSPx, x = H2SO4,HNO3, HCl) were prepared using a hydrothermal method. The prepared TCMSPx were characterized in terms of visual, physical and chemical properties. The photocatalytic activity of the TCMSPx was evaluated via the photodegradation of 2,4-dichlorophenol (2,4-D) in aqueous solution. The results showed that the characteristics and photocatalytic activity of TCMSPx were strongly affected by acidic solutions used during the acidolysis. TCMSPH2SO4 exhibited better characteristics and higher photocatalytic activity than TCMSPHNO3 and TCMSPHCl. OH radicals from TCMSPH2SO4 were produced under UV, visible and solar light irradiation. The degree of photodegradation of 2,4-D by TCMSPH2SO4 was 80.1%, 50.0% and 61.5% under UV, visible and solar light irradiation respectively. In addition, the removal of chlorine functional group on the 2,4-D benzene ring and the production of intermediates during 2,4-D photodegradation were monitored using ion chromatography, UV–vis spectra and high performance liquid chromatography of 2,4-D before and after photodegradation.

Inhibitory effect of 2,4-dichlorophenol on nitrogen removal in a sequencing batch reactor

Jun-Wei Lim,Si-Ling Ng,Siok-Moi Khor,Chye-Eng Seng 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.7

We examined the inhibitory effect of 2,4-dichlorophenol (2,4-DCP) on nitrogen removal in the sequencing batch reactor (SBR) system. The reactor was operated with FILL, REACT (nitrification: denitrification), SETTLE,DRAW and IDLE phases in the duration ratio of 2 : 12 (9 : 3) : 1 : 1 : 8 for a 24 h cycle time. The deterioration of 2,4-DCP removal efficiency from 100 to 41% was observed when the influent concentration of 2,4-DCP was increased to 30mg/L. The residual 2,4-DCP remaining in the mixed liquor was found to inhibit the nitrification process, resulting in the decrease of nitrogen removal efficiency to 25 %. For kinetic study, the result showed that the experimental data of ammoniacal nitrogen (AN) removal at every stage fitted well to the first-order kinetics equation with high R2 values. The rate constant of AN removal, kAN, decreased with increasing influent concentration of 2,4-DCP, from 0.053 to 0.0006/min when 2,4-DCP concentration increased from 0 to 30 mg/L, respectively. However, the observed gradual recovering of AN removal with respect to the removal efficiency and kinetics during the recovery stage indicated that the inhibitory effect of 2,4-DCP on the nitrification process was reversible.

합성수지 흡착제에 의한 p-Chlorophenol 및 2,4-Dichlorophenol의 액상흡착평형특성에 관한 연구

류정 ( Lyu Jeong ),김현규 ( Kim Hyeon Gyu ),원성호 ( Won Seong Ho ),황상면 ( Hwang Sang Myeon ),김상민 ( Kim Sang Min ),김남기 ( Kim Nam Gi ),이용철 ( Lee Yong Cheol ) 한국공업화학회 2003 공업화학 Vol.14 No.5

Rohm & Haas사에 의해 제조된 합성수지 흡착제, Amberlite XAD-4, XAD-7 및 XAD-1180을 사용하여 수용액상의 파라클로로페놀(p-chlorophenol) 및 2,4-디클로로페놀(2,4-dichlorophenol)의 흡착평형에 대한 특성들이 연구되었다. 흡착평형에 대한 실험결과들은 8가지 흡착등온식에 대한 비선형 회귀분석을 통해 이론적으로 고찰되었다. 실험 자료에 대한 회기분석 결과, 각 합성수지 흡착제에 대한 파라클로로페놀 및 2,4-디클로로페놀의 흡착거동은 BET 등온식, Four-parameter 등온식, Freundlich 등온식, Redlich-Petersen 등온식 및 Slips 등온식을 통해 4.31%의 오차범위 내에서 성공적으로 재현되었으나 Langmuir 등온식 및 Toth 등온식에 의해서는 최대 8.49%의 오차로서 다른 등온식들에 비하여 비교적 높은 오차분포를 갖는 결과를 보였다. Adsorption equilibrium characteristics of p-chlorophenol and 2,4-dichlorophenol on the polymeric synthetic adsorbents, Amberlite XAD-4, XAI-7 and XAD-1180 manufactured by Kohm & Haas Co.. in the aqueous solution were investigated by experimental tests and theoretical analyses. To evaluate theoretically experimental isotherms, eight adsorption equations and regressional methods were used. From the nonlinear regressional analyses adsorption equilibrium behaviors of p-chlorophenol and 2.3-dichlorophenol with polymeric synthetic adsorbents were successfully reproduced by BET isotherm, Four-parameter isotherm. Freundlich isotherm. Loading ratio correlation isotherm, Redlich-Petersen isotherm and Sips isotherm within the deviation of 4.31 %. But the results were not good for Langmuir isotherm and Toth isotherm with the upper deviation of 8.49 %.

Degradation of 2,4-dichlorophenol in aqueous solution by sono-Fenton method

이창수,Praveena Juliya Dorathi. Ranjit,Kandasany Palanivelu 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.1

This study presents the results of the Sono-Fenton process for the degradation of 2,4-dichlorophenol (DCP). The influential parameters such as H2O2, Fe2+ and pH for the Sono-Fenton process were investigated. Sono-Fenton method was found to be the best one for degradation efficiency of DCP when compared with that of the Fenton process. The optimum concentrations for the degradation of DCP using conventional Fenton’s method were found to be 20 mg/ L of Fe2+ and 580 mg/L of H2O2 at pH 2.5. In the case of Sono-Fenton, the optimal concentrations were found to be 10 mg/L of Fe2+ and 400 mg/L of H2O2 at pH 2.5. Sono-Fenton method resulted in the reduction of required Fe2+ concentration (50%) and H2O2 concentration (31%). In addition, this method could be applicable even at pH 5.0 and a degradation efficiency of DCP was 77.6%. Kinetic studies for the degradation of DCP proved that the degradation of DCP tends to follow pseudo first order reaction and the rate constant was found to be 7×10−4 min−1.

Kinetic Analysis for Decomposition of 2,4-Dichlorophenol by Supercritical Water Oxidation

이창하,황경엽,이현철,Jung-Hyun In,Jong-Hwa Kim 한국화학공학회 2005 Korean Journal of Chemical Engineering Vol.22 No.6

2,4-Dichlorophenol (2,4-DCP), as a halogenated model pollutant, was decomposed by using supercritical water oxidation (SCWO) in a batch reactor made of Hastelloy C-276. SCWO experiments for 2,4-DCP decomposition were performed in the range of 380-420 oC, 230-280 bar and 0.074- 0.221 mol/L H2O2. The effect of oxidant concentration on decomposition rate and efficiency was significant near the critical temperature of 380 oC. However, the role of the oxidant concentration in the SCWO process decreased with an increase in temperature; also, excess oxidant played a key role in quite significantly decreasing the activation energy of 2,4-DCP oxidation. Variation of the reaction rate by the change of pressure was negligible even at a near critical temperature. The kinetic rate for the decomposition of 2,4-DCP in the SCWO process was well described by a simple first-order kinetic and global reaction rate model. From the SCWO experiments, the various intermediates identified with a GC/MS implied that the first reaction pathway for 2,4-DCP decomposition led to dimers such as dichlorophenoxyphenols, and the second led to single-ring and ringopening products.

2,4-Dichlorophenol Enzymatic Removal and Its Kinetic Study Using Horseradish Peroxidase Crosslinked to Nano Spray-Dried Poly(Lactic-Co-Glycolic Acid) Fine Particles

( Laura Amina Dahili ),( Endre Nagy ),( Tivadar Feczko ) 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.4

Horseradish peroxidase (HRP) catalyzes the oxidation of aromatic compounds by hydrogen peroxide via insoluble polymer formation, which can be precipitated from the wastewater. For HRP immobilization, poly(lactic-co-glycolic acid) (PLGA) fine carrier supports were produced by using the Nano Spray Dryer B-90. Immobilized HRP was used to remove the persistent 2,4- dichlorophenol from model wastewater. Both extracted (9-16 U/g) and purified HRP (11- 25 U/g) retained their activity to a high extent after crosslinking to the PLGA particles. The immobilized enzyme activity was substantially higher in both the acidic and the alkaline pH regions compared with the free enzyme. Optimally, 98% of the 2,4-dichlorophenol could be eliminated using immobilized HRP due to catalytic removal and partly to adsorption on the carrier supports. Immobilized enzyme kinetics for 2,4-dichlorophenol elimination was studied for the first time, and it could be concluded that competitive product inhibition took place.

Purification and Characterization of 2,4-Dichlorophenol Oxidizing Peroxidase from Streptomyces sp. AD001

( Jeong Ho Jeon ) 한국미생물생명공학회 2002 Journal of microbiology and biotechnology Vol.12 No.6

Adsorption of 2,4-dichlorophenol on metal-nitrate modified activated carbon

Kanagasabai Muruganandam Ponvel,Dhamodaran Kavitha,Kyung-Min Kim,이창하 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.5

To remove 2,4-dichlorophenol (2,4-DCP) from aqueous solution, the surface of the activated carbon was first treated with HCl and then the surface was modified by using various metal ions (Cu, Co, Fe, Ni, Zn, and Mg). Metal doping significantly enhanced the adsorption efficiency of activated carbon, an effect that was further increased by HCl treatment of the modified activated carbons. Of all the preparations, the zinc(Ⅱ)-modified activated carbon with HCl treatment showed the highest adsorption capacity for 2,4-DCP. Analysis of the zinc(Ⅱ)-modified activated carbon by SEM and BET showed a surface area and micropore volume of around 1,154.69 ㎡/g and 0.291 ㎤/g, respectively, values about 20% higher than in the starting material. In the pH range of 2.0-11.0, the maximum uptake of 2,4- DCP from an initial concentration of 1,000 mg/L was 508 mg/g at pH 4.0.

Heterogeneous photodegradation of 2,4-dichlorophenol using FeO doped onto nano-particles of zeolite P

Alireza Nezamzadeh-Ejhieh,Zahra Ghanbari-Mobarakeh 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

Photocatalytic degradation of 2,4-dichlorophenol was studied using FeO-doped onto nano-particles ofzeolite P (FeO–NP). FeO/NP was prepared by ion exchange and calcination procedures. The samples werecharacterized by FT-IR, SEM and DRS. UV–vis, HPLC and COD were employed to calculate the degradationextent of the pollutant. The results confirmed that the degradation efficiency of the method stronglydependent to experimental parameters such as: pH, catalyst concentration, substrate concentration,active component value (FeO) loading, presence of H2O2 and inorganic Cl and SO42 anions. The firstorderkinetics model was used to study the kinetics of the method.