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Simultaneous Removal of Lignin and 2,4-Dichlorophenol in Pulp and Paper Mill Wastewater Using a Supervibration-photocatalytic Reactor  [cached]
Suchanya Thongkrua,Chavalit Ratanatamskul
Modern Applied Science , 2011, DOI: 10.5539/mas.v5n1p92
Abstract: Advanced photocatalytic degradation of lignin and 2,4-dichlorophenol (2,4-DCP) was studied. The method used a newly developed supervibration-photocatalytic reactor based on the photocatalytic process combined with a supervibration agitator. Effects of operating conditions such as initial pH, UV intensity and supervibration frequency on removal efficiency were investigated. From the results obtained, removal efficiencies of lignin and 2,4-DCP were similar pattern. UV intensity and supervibration frequency in a low initial pH increased removal efficiencies of lignin and 2,4-DCP. The optimum operating condition for a supervibration-photocatalytic reactor was found at initial pH 5, 25.2mW/cm2 UV intensity and 50Hz supervibration frequency. Under the optimum treatment condition, the reactor could simultaneously remove lignin and 2,4-DCP up to 75.1% and 94.1%, respectively within 420min.
Comparative analysis of ZnO-catalyzed photo-oxidation of p-chlorophenols  [cached]
Umar Ibrahim Gaya
European Journal of Chemistry , 2011, DOI: 10.5155/eurjchem.2.2.163-167.369
Abstract: The present study compares for the first time the photocatalytic oxidation of three p-chlorophenols (4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol) in irradiated ZnO suspensions. The effect of operating parameters such as catalyst and concentration doses on the decomposition rate of these p-chlorinated compounds has been studied and optimized. The optimal feed concentration for each of the chlorinated phenolic compounds is 50 mg/L whereas the ZnO doses decreased as the number of chlorine substituent is increased. Kinetic profiles on the decomposition of chlorophenols over ZnO agreed with the pseudo-zeroeth order rate scheme with rate constants following the order 2,4,6-trichlorophenol > 2,4-dichlorophenol > 4-chlorophenol. The validity of the pseudo zero order model could be linked to the initial doses of the chlorophenols used vis-à-vis the catalyst. The study revealed stable intermediates of photocatalytic chlorophenol transformation by high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) technique. A combined mechanism is given to account for the photocatalytic destruction of the chlorophenols.
Nonlinear Modelling of Kinetic Data Obtained from Photocatalytic Mineralisation of 2,4-Dichlorophenol on a Titanium Dioxide Membrane  [PDF]
Ignazio Renato Bellobono,Roberto Scotti,Massimiliano D'Arienzo,Franca Morazzoni,Riccardo Bianchi,Rodica Stanescu,Cristina Costache,Liliana Bobirica,Gabriela Cobzaru,Paola Maria Tozzi,Mauro Rossi,Mauro Luigi Bonardi,Flavia Groppi,Luigi Gini
International Journal of Photoenergy , 2009, DOI: 10.1155/2009/631768
Abstract: Photomineralisation of 2,4-dichlorophenol (DCP) in aqueous solutions (10.0–100.0 mg/L of C) was systematically studied at 318±3 K, in an annular laboratory-scale reactor, by photocatalytic membranes immobilizing titanium dioxide, as a function of substrate concentration, and absorbed power per unit length of membrane. Kinetics of both substrate disappearance, to yield intermediates, and total organic carbon (TOC) disappearance, to yield carbon dioxide, were followed (first series of experiments). At a fixed value of irradiance (1.50 W?cm?1), other series of mineralization experiments were repeated (second series of experiments) by carrying out only analyses of chemical oxygen demand (COD), in order to compare modelling results of the two sets of experiments. In both sets of experiments, stoichiometric hydrogen peroxide was used as oxygen donor. For the first series of experiments, a kinetic model was employed, already validated in previous work, from which, by a set of differential equations, four final optimised parameters, 1 and 1, 2 and 2, were calculated. By these parameters, the whole kinetic profile could be fitted adequately. The influence of irradiance on 1 and 2 could be rationalised very well by this four-parameter kinetic model. Modelling of quantum yields, as a function of irradiance, could also be carried out satisfactorily. As has been found previously for other kinds of substrates, modelling of quantum yields for DCP mineralization is consistent with kinetics of hydroxyl radicals reacting between themselves, leading to hydrogen peroxide, other than with substrate or intermediates leading finally to carbon dioxide, paralleled by a second competition kinetics involving superoxide radical anion. For the second series of experiments, on the contrary, the Langmuir-Hinshelwood model was employed. Uncertainties of COD analyses, coupled with discrepancies of this model and with its inability to reproduce kinetics up to complete mineralization, are underlined.
The removal of 2,4-dichlorophenol under visible light irradiation by silver indium sulfide nanoparticles synthesized by microwave  [PDF]
Azadeh Tadjarodi,Amir Hossein,Cheshme khavar,Mina Imani
Current Chemistry Letters , 2013,
Abstract: Silver indium sulfide (AgInS2) nanoparticles were synthesized by microwave method. These nanopartricles were characterized by FT-IR, XRD, DRS, SEM and TEM techniques. The band gap energy of 1.96 eV was determined by UV-Vis diffuse reflection spectrum (DRS). The photocatalytic activity was studied by photodegradation reaction of 2,4-dichlorophenol (2,4-DCP) under visible light irradiation. The influence of initial concentration, initial solution pH on the degradation percentage of 2,4-DCP and also, the kinetics of photodegradation were investigated. The removal efficiency up to 95% proved the superior capability of AgInS2 (AIS) nanoparticles for water purification.
Biodegradation of 2,4-dichlorophenol originating from pharmaceutical industries
AZ Elkarmi, KH Abu-Elteen, AA Atta, NA Abu-Sbitan
African Journal of Biotechnology , 2009,
Abstract: The aims of this work were to isolate a microorganism from the wastewater of pharmaceutical industries, to examine the difference in its growth utilization of 2,4-dichlorophenol as the sole carbon source pre and post-exposure to UV-irradiation and to investigate its efficiency of biodegradation at different temperatures and pH values using a laboratory benchtop bioreactor. Sludge was obtained from the wastewater and standard isolation and identification techniques were used to identify the microorganism. The biodegradability was tested at temperatures of 25, 30, 35 and 40°C and at pH values of 6.5, 7.0 and 8.0. The results indicated that the isolated microorganism was Pseudomonas alcaligenes, the maximum concentration of 2,4-dichlorophenol which bacteria can grow on before UVirradiation was 220 and 380 mg/l after UV-irradiation. The variation in temperature values resulted in different degradation rates and that the degradation of 2,4-dichlorophenol increased at a higher pH value. From these results, it is concluded that P. alcaligenes can be used for the degradation of 2,4-dichlorophenol, UV-irradiation can be successfully used for the improvement of P. alcaligenes biodegradability and that the best 2,4-dichlorophenol biodegradation was at 35°C and pH 7.
Biodegradation of 2,4 dichlorophenol by Pleurotus ostreatus DSM 1833
Silva, Heloisa Helena Batista da;Schneider, Andréa Lima dos Santos;Wisbeck, Elisabeth;Furlan, Sandra Aparecida;
Brazilian Archives of Biology and Technology , 2009, DOI: 10.1590/S1516-89132009000600028
Abstract: this work aimed to investigate the capacity of pleurotus ostreatus dsm 1833 to degrade 2,4-dichlorophenol, important pollutant found in the wastewaters of the paper and cellulose industry. using a factorial design 22, the concentrations of glucose and 2,4-dichlorophenol varied between 0 and 10g.l-1 and 5 and 30mg.l-1, respectively. the best global biodegradation rate was obtained using 30 mg.l-1 of 2,4- dichlorophenol in the absence of glucose. this culture medium was used for scaling up the process, resulting in a global biodegradation rate of 0.47mg.l-1.h-1. a comparative test between an inoculated medium and an abiotic control demonstrated that 54.1% of 2,4- dichlorophenol degradation could be attributed to the presence of p. ostreatus.
Biodegradation of 2,4-dichlorophenol using Mycoplana dimorpha extracts and evaluation of kinetic parameters
R Manikandan, HJ Prabhu, P Sivashanmugam
African Journal of Biotechnology , 2008,
Abstract: Twenty seven combinations of process variables were developed and used to produce crude extracts of Mycoplana dimorpha. Crude extracts containing 2,4-dichlorophenol degrading enzymes, were immobilized on sodium alginate beads and degradation studies was conducted in a packed bed column. The rate of degradation of 2,4-dichlorophenol by immobilized crude extracts of was measured at different time intervals and it was found that 82 to 86% of 2,4-dichlorophenol can be decomposed with different initial concentrations in 30 min. The Km and Vmax values were determined.
Characterization of nanoscale iron and its degradation of 2,4-dichlorophenol
ChunFeng Hou,XiaoPeng Ge,YanMei Zhou,Yi Li,DongSheng Wang,HongXiao Tang
Chinese Science Bulletin , 2010, DOI: 10.1007/s11434-009-0676-3
Abstract: Nanoscale iron was detected by TEM, X-ray diffraction and X-ray photoelectron spectroscopy. It was found that the size of the nanoscale iron particles is in the range of 30–40 nm according to TEM image, and it contains abundant Fe3O4 as passivating layers on the surface of the core-shell structure. To improve its performance, dilute HCl was used for the removal of the passivating layers, and the degradation of 2,4-dichlorophenol (2,4-DCP) was measured for the nanoscale iron samples treated and untreated. Experimental results demonstrated that the removal of 2,4-DCP by untreated nanoscale iron is mainly due to the adsorption of 2, 4-DCP by nanoscale iron, and there are no degradation products detected by HPLC in the process. However, excellent dechlorination of 2,4-DCP was gained by HCl-treated nanoscale iron, and 2-chlorophenol, 4-chlorophenol and phenol were detected during the process. It was concluded that dechlorination is the key reaction pathway for the degradation of 2,4-DCP by activated nanoscale iron, and phenol is found to be the main product.
Studies on Physicochemical Properties of Biofield Treated 2,4-Dichlorophenol
Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Ragini Singh, Snehasis Jana
American Journal of Environmental Protection , 2015, DOI: 10.11648/j.ajep.20150406.15
Abstract: The chlorinated phenols are widely used in chemical industries for the manufacturing of herbicides, insecticides, etc. However, due to consistent use they create hazards to the environment. This study was designed to use an alternative method i.e. biofield energy treatment and analyse its impact on the physicochemical properties of 2,4-dichlorophenol (2,4- DCP), which are the important factors related to its degradation. The 2,4-DCP sample was treated with Mr. Trivedi’s biofield energy and analyzed as compared to the untreated 2,4-DCP sample (control) using various analytical techniques. The X-ray diffraction studies revealed up to 19.4% alteration in the lattice parameters along with approximately 1.8% alteration in the molecular weight, unit cell volume and density of the treated sample. The crystallite size of treated sample was increased and found as 215.24 nm as compared to 84.08 nm in the control sample. Besides, the thermal study results showed an alteration in the thermal stability profile of the treated sample as compared to the control. The differential scanning calorimetry studies revealed the decrease in the thermal decomposition temperature from 137.9°C (control) to 131.94°C in the treated sample along with 92.19% alteration in the quantity of heat absorbed during the process. Moreover, the thermogravimetric analysis showed that onset temperature of degradation was decreased, while the percent weight loss of the sample was increased from 59.12% to 71.74% in the treated sample as compared to the control. However, the Fourier transform infrared and UV-visible spectroscopic studies did not show any significant alteration in the spectra of the treated sample as compared to the control. Hence, the overall studies revealed the impact of biofield energy treatment on the physical and thermal properties of the 2,4- DCP sample.
Study on preparation of resene and its adsorbing 2,4-dichlorophenol in aqueous solutions
氧化树脂的制备及其对水溶液中2,4-二氯苯酚的吸附研究

Qian Xiaorong,Wang Lianjun,Mao Airong,Pan Mei,
钱晓荣
,王连军,冒爱荣,潘梅

环境工程学报 , 2008,
Abstract: New polymeric adsorbents oxidized by oxydol (ZH-07) or nitric acid(ZH-08)group for adsorbing 2,4-dichlorophenol were prepared. The static adsorption characteristics for 2,4-dichlorophenol onto them at different temperatures were studied and their adsorption mechanism were further investigated and compared. The result shows that chemisoption will be in existence in the adsorption process of 2,4-dichlorophenol in aqueous solutions with NDA150 oxidized and the adsorption capacities of 2,4-dichlorophenol in aqueous solutions with resene will be improved.
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