Photodegradation of Dimethyl Phthalate by Fe(III)/Oxalate/H2O2 System

2012 ◽  
Vol 550-553 ◽  
pp. 2412-2415 ◽  
Author(s):  
Xiang Hua Feng ◽  
Jun Zhou ◽  
Shi Min Ding
Keyword(s):  
Ph Value ◽  
Degradation Efficiency ◽  
Light Sources ◽  
Dimethyl Phthalate ◽  
Photochemical Process ◽  
Photodegradation Efficiency ◽  
Optimum Ph ◽  
Initial Ph ◽  
High Level ◽  
Metal Halide Lamps

Photodegradation of dimethyl phthalate (DMP) in aqueous solutions by Fe(III)/oxalate/H2O2 system was investigated using daylight lamps as main light source. The UV-Vis spectra of the system and the concentration of •OH generated during irradiation were detected. The influences such as light sources, initial pH value, initial concentration of reactants on photodegradation efficiency of DMP were discussed. This system has advantage in appling visible light to produce •OH. DMP degradation efficiency principally depend on the concentration of •OH produced from photochemical process of the system. Several light sources including daylight lamps, metal halide lamps, UV disinfecting lamp and sunlight can all be as the light sources to achieve DMP degradation. DMP degradation efficiency keeps on a high level over the range of pH 3.0 to 5.0 and the optimum pH is 3.0. The degradation rate of DMP increases with increase of the initial concentrations of Fe(III) and H2O2, whereas decreases with increase of the initial concentrations of oxalate.

Photodegradation of Dimethyl Phthalate Induced by Photolysis of Fe(III)-Pyruvate Complex

2012 ◽  
Vol 518-523 ◽  
pp. 2653-2656
Author(s):  
Xiang Hua Feng ◽  
Liang Ding ◽  
Shi Min Ding
Keyword(s):  
Ph Value ◽  
Degradation Efficiency ◽  
Uv Disinfection ◽  
Light Sources ◽  
Dimethyl Phthalate ◽  
Initial Concentration ◽  
Photodegradation Efficiency ◽  
Optimum Ph ◽  
Initial Ph ◽  
Metal Halide Lamps

Photodegradation of dimethyl phthalate (DMP) in aqueous solutions by Fe(III)-pyruvate complex system was preliminarily investigated. The influences such as light sources, initial pH value, initial concentration of Fe(III), pyruvate and DMP on photodegradation efficiency of DMP were discussed in detail. The result indicates that DMP could be decomposed efficiently in Fe(III)-pyruvate system. The degradation efficiency of DMP are dependent on initial pH value, Fe (III) initial concentration and pyruvate initial concentration. The optimum pH for photodegration of DMP is 3.0. The degradation efficiency of DMP increases with increase of the initial concentrations of Fe(III) or pyruvate, whereas decreases with increase of the initial concentrations of DMP. Various light sources including metal halide lamps, daylight lamps, UV disinfection lamps and sunlight can be adopted in the system.

scholarly journals Biodegradation of Dimethyl Phthalate by Freshwater Unicellular Cyanobacteria

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaohui Zhang ◽  
Lincong Liu ◽  
Siping Zhang ◽  
Yan Pan ◽  
Jing Li ◽  
...  
Keyword(s):  
Degradation Product ◽  
Phthalic Acid ◽  
Ph Value ◽  
Degradation Process ◽  
Degradation Efficiency ◽  
Culture Solution ◽  
Optimum Temperature ◽  
Dimethyl Phthalate ◽  
Initial Ph ◽  
Unicellular Organisms

The biodegradation characteristics of dimethyl phthalate (DMP) by three freshwater unicellular organisms were investigated in this study. The findings revealed that all the organisms were capable of metabolizing DMP; among them, Cyanothece sp. PCC7822 achieved the highest degradation efficiency. Lower concentration of DMP supported the growth of the Cyanobacteria; however, with the increase of DMP concentration growth of Cyanobacteria was inhibited remarkably. Phthalic acid (PA) was detected to be an intermediate degradation product of DMP and accumulated in the culture solution. The optimal initial pH value for the degradation was detected to be 9.0, which mitigated the decrease of pH resulting from the production of PA. The optimum temperature for DMP degradation of the three species of organisms is 30°C. After 72 hours’ incubation, no more than 11.8% of the residual of DMP aggregated in Cyanobacteria cells while majority of DMP remained in the medium. Moreover, esterase was induced by DMP and the activity kept increasing during the degradation process. This suggested that esterase could assist in the degradation of DMP.

scholarly journals Comparison of sorption efficiency of natural and MnO2 coated zeolite for copper removal from model solutions

2021 ◽  
Vol 900 (1) ◽  
pp. 012003
Author(s):  
M Balintova ◽  
Z Kovacova ◽  
S Demcak ◽  
Y Chernysh ◽  
N Junakova
Keyword(s):  
Heavy Metals ◽  
Removal Efficiency ◽  
Ph Value ◽  
Batch Experiments ◽  
Modified Zeolite ◽  
Optimum Ph ◽  
Removal Of Heavy Metals ◽  
Initial Ph ◽  
Correlation Factors ◽  
Maximum Removal

Abstract Removal of heavy metals from the environment is important for living beings. The present work investigates the applicability of the natural and MnO2 - coated zeolite as sorbent for the removal of copper from synthetic solutions. Batch experiments were carried out to identify the influence of initial pH and concentration in the process of adsorption. A maximum removal efficiency of Cu(II) was observed in 10 mg/L for natural (95.6%) and modified (96.4%) zeolite, where the values was almost identical, but at concentration of 500 mg/L was the removal efficiency of modified zeolite three times higher. Based on the correlation factors R2, the Langmuir isotherms better describe the decontamination process than Freundlich. The optimum pH value was set at 5.0.

scholarly journals Sorption Efficiency of a New Sorbent towards Cadmium(II): Methylphosphonic Acid Grafted Polystyrene Resin

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Nacer Ferrah ◽  
Omar Abderrahim ◽  
Mohamed Amine Didi ◽  
Didier Villemin
Keyword(s):  
Metal Ion ◽  
Ph Value ◽  
Ion Concentration ◽  
Methylphosphonic Acid ◽  
Order Kinetic ◽  
Elementary Analysis ◽  
Optimum Ph ◽  
Initial Ph ◽  
Pseudo Second Order ◽  
Polystyrene Resin

A new chelating polymeric sorbent has been developed using polystyrene resin grafted with phosphonic acid. After characterization by FTIR and elementary analysis, the new resin has been investigated in liquid-solid extraction of cadmium(II). The results indicated that phosphonic resin could adsorb Cd(II) ion effectively from aqueous solution. The adsorption was strongly dependent on the pH of the medium and the optimum pH value level for better sorption was between 3.2 and 5.2. The influence of other analytical parameters including contact time, amount of resin, metal ion concentration, and the presence of some electrolytes was investigated. The maximum uptake capacity of Cd(II) ions was 37,9 mg·g−1grafted resin at ambient temperature, at an initial pH value of 5.0. The overall adsorption process was best described by pseudo second-order kinetic. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. Furthermore, more than 92% of Cd(II) could be eluted by using 1.0 mol·L−1HCl in one cycle.

Expression, Enzymatic Characterization, and High-Level Production of Glucose Isomerase from Actinoplanes missouriensis CICIM B0118(A) in Escherichia coli

2011 ◽  
Vol 66 (11-12) ◽  
pp. 605-613 ◽  
Author(s):  
He Wang ◽  
Ruijin Yang ◽  
Xiao Hua ◽  
Zhong Zhang ◽  
Wei Zhao ◽  
...  
Keyword(s):  
Ph Value ◽  
Glucose Isomerase ◽  
Medium Composition ◽  
Gene Encoding ◽  
E Coli ◽  
Optimum Ph ◽  
One Step ◽  
Ph Range ◽  
High Level ◽  
Level Production

High-level production of recombinant glucose isomerase (rGI) is desirable for lactulose synthesis. In this study, the xylA gene encoding glucose isomerase from Actinoplanes missouriensis CICIM B0118(A) was cloned and expressed in E. coli BL21(DE3), and high-level production was performed by optimization of the medium composition. rGI was purified from a recombinant E. coli BL21(DE3) and characterized. The optimum pH value of the purified enzyme was 8.0 and it was relatively stable within the pH range of 7.0 - 9.0. Its optimum temperature was around 85 °C, and it exhibited good thermostability when the temperature was lower than 90 °C. The maximum enzyme activity required the presence of both Co2+ and Mg2+, at the concentrations of 200 μM and 8 mM, respectively. With high-level expression and the simple one-step chromatographic purification of the His-tagged recombinant enzyme, this GI could be used in industrial production of lactulose as a potential economic tool

Optimum and Efficiency of Chloramphenicol Degradation by UV/H2O2 Process

2013 ◽  
Vol 838-841 ◽  
pp. 2677-2680 ◽  
Author(s):  
Yan Bo Li ◽  
Cui Ping Wang ◽  
Ming Yue Zheng ◽  
Kai Jun Wang
Keyword(s):  
Reaction Time ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Ph Value ◽  
Advanced Oxidation ◽  
Degradation Efficiency ◽  
Complete Degradation ◽  
Initial Ph ◽  
Operation Parameters

Degradation of chloramphenicol (CAP) by an advanced oxidation process, UV/H2O2, was investigated. Firstly, effect of H2O2 concentration, initial pH value, K2S2O8 concentration and reaction time on chloramphenicol degradation by UV/H2O2 process was studied. In addition, all the operation parameters mentioned above were optimized. The results showed that the degradation efficiency of CAP can be obviously enhanced with increasing both H2O2 concentration and K2S2O8 concentration. Moreover, initial pH value had unapparent impact on the efficiency of chloramphenicol degradation. Nearly complete degradation of chloramphenicol was achieved under the conditions of H2O2 concentration 2mM, initial pH value 7.7, K2S2O8 concentration 1mM and reaction time 15min.

scholarly journals Decoloration of methylene blue simulated wastewater using a UV-H2O2 combined system

2011 ◽  
Vol 1 (1) ◽  
pp. 45-51 ◽  
Author(s):  
L. V. Jian-xiao ◽  
Cui Ying ◽  
Xie Guo-hong ◽  
Zhou Ling-yun ◽  
Wang Su-fen
Keyword(s):  
Methylene Blue ◽  
Ph Value ◽  
Order Kinetic ◽  
Combined System ◽  
Initial Stage ◽  
Optimum Ph ◽  
Initial Ph ◽  
Simulated Wastewater ◽  
Kinetics Of ◽  
Order Kinetic Equation

Methylene blue simulated wastewater was treated with a UV-H2O2 combined system. Influences of factors such as reaction time, initial pH value and H2O2 dosage were investigated, and the reaction kinetics of the process was explored. Results showed that the degradation of methylene blue happened only in the presence of both conditions: UV irradiation and H2O2 addition. Initial pH and H2O2 dosage had a remarkable influence on the degradation efficiency. Through several groups of univariate experiments, the optimum pH and H2O2 dosage of the photolysis process were found to be 4–5 and 0.165 mL 30% H2O2 per milligram of methylene blue, respectively. The photolysis process was relatively fast at the initial stage and, 20 min later, it was approximately in accordance with the first-order kinetic equation.

scholarly journals Physical Properties of PVDF-GO/Black-TiO2 Nanofibers and its Photocatalytic Degradation of Methylene Blue and Malachite Green Dyes

2020 ◽  
Author(s):  
M K Abdelmaksoud ◽  
Alaa Mohamed ◽  
Abderrahman Sayed ◽  
S A Khairy
Keyword(s):  
Methylene Blue ◽  
Graphene Oxide ◽  
Malachite Green ◽  
Diffuse Reflectance Spectroscopy ◽  
Ph Value ◽  
Degradation Efficiency ◽  
Tio2 Nanofibers ◽  
Particle Distributions ◽  
Optimum Ph ◽  
Visible Light Driven

Abstract BackgroundBlack TiO2 and Graphene Oxide (GO) have attracted intensive attention as an effective catalyst on visible light driven for photodegrading of dyes. In this study, nano-black TiO2 was prepared by a simple hydrogenation of the anatase titanium oxide and the graphene oxide was prepared by applying the modified Hummers method. The prepared powders and nanofiber membranes are carefully examined to ensure their single phase and compound structure formation as well as to measure the equivalent crystallite size and particle distributions. ResultsThe optimum degradation efficiency of malachite green and methylene blue dyes occurred at pH values of 8 and 10, respectively. Afterwards, at the optimum pH value of 8, for malachite green, the degradation efficiency is peaked at 20 mg of the nano-black TiO2 concentration. Then, a comparison of the degradation efficiency of the two mentioned dyes are performed as the fore-mentioned nanofibers are loaded with 20 mg nano-black TiO2 at the corresponding optimum pH vales. ConclusionsThe diffuse reflectance spectroscopy has been investigated to find out the optical energy gaps of the treated and nano-black samples. Finally, a schematic of the redox reaction mechanism has been proposed.

scholarly journals Silica Removal from a Paper Mill Effluent by Adsorption on Pseudoboehmite and γ-Al2O3

Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2031
Author(s):  
Ruben Miranda ◽  
Isabel Latour ◽  
Angeles Blanco
Keyword(s):  
Paper Mill ◽  
Ph Adjustment ◽  
Paper Mill Effluent ◽  
Kinetics Studies ◽  
Silica Removal ◽  
Industrial Water Use ◽  
Optimum Ph ◽  
Initial Ph ◽  
Equilibrium And Kinetics ◽  
Kinetics Of

Effluent reuse is a common practice for sustainable industrial water use. Salt removal is usually carried out by a combination of membrane processes with a final reverse osmosis (RO). However, the presence of silica limits the RO efficiency due to its high scaling potential and the difficulty of cleaning the fouled membranes. Silica adsorption has many advantages compared to coagulation and precipitation at high pHs: pH adjustment is not necessary, the conductivity of treated waters is not increased, and there is no sludge generation. Therefore, this study investigates the feasibility of using pseudoboehmite and its calcination product (γ-Al2O3) for silica adsorption from a paper mill effluent. The effect of sorbent dosage, pH, and temperature, including both equilibrium and kinetics studies, were studied. γ-Al2O3 was clearly more efficient than pseudoboehmite, with optimal dosages around 2.5–5 g/L vs. 7.5–15 g/L. The optimum pH is around 8.5–10, which fits well with the initial pH of the effluent. The kinetics of silica adsorption is fast, especially at high dosages and temperatures: 80–90% of the removable silica is removed in 1 h. At these conditions, silica removal is around 75–85% (<50 mg/L SiO2 in the treated water).

scholarly journals Hydrothermal Synthesis of Various Shape-Controlled Europium Hydroxides

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 529
Author(s):  
Hongjuan Zheng ◽  
Kongjun Zhu ◽  
Ayumu Onda ◽  
Kazumichi Yanagisawa
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ph Value ◽  
Hydrothermal Temperature ◽  
X Ray ◽  
Hydrothermal Reactions ◽  
Starting Solution ◽  
Initial Ph ◽  
Shape Controlled ◽  
Scanning Electron

Eu(OH)3 with various shape-controlled morphologies and size, such as plate, rod, tube, prism and nanoparticles was successfully synthesized through simple hydrothermal reactions. The products were characterized by XRD (X-Ray Powder Diffraction), FE-SEM (Field Emission- Scanning Electron Microscopy) and TG (Thermogravimetry). The influence of the initial pH value of the starting solution and reaction temperature on the crystalline phase and morphology of the hydrothermal products was investigated. A possible formation process to control morphologies and size of europium products by changing the hydrothermal temperature and initial pH value of the starting solution was proposed.

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