Solid Super Acid of S2O82- /FexOy-CuOx Catalytic Degradation of Orange IV

Solid super acid (S2O82-/FexOy-CuOx) was prepared and used as a heterogeneous Fenton-like catalyst to decompose H2O2for the degradation of refractory dye Orange IV in water. The factors that affected the degradation of Orange IV were discussed in this heterogeneous Fenton-like system. The catalytic activity of S2O82-/FexOy-CuOxwas evaluated by the degradation of Orange IV and the decomposition of H2O2. The results show that the catalyst S2O82-/FexOy-CuOxhas a good catalytic activity. The reaction follows pseudo-first-order kinetics; the reaction rate constant has a good relationship with the concentration of H2O2. The degradation rate of Orange IV and the decomposition rate of H2O2increase with the increase of temperature and the dosage of catalyst whereas it decreases with the increase of the initial concentration of Orange IV and the initial pH.

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Efficient degradation of naproxen by persulfate activated with zero-valent iron: performance, kinetic and degradation pathways

Water Science & Technology ◽

10.2166/wst.2020.263 ◽

2020 ◽

Vol 81 (10) ◽

pp. 2078-2091

Author(s):

Shuyu Dong ◽

Xiaoxue Zhai ◽

Ruobing Pi ◽

Jinbao Wei ◽

Yunpeng Wang ◽

...

Keyword(s):

Aqueous Solution ◽

Hydroxyl Radical ◽

Rate Constants ◽

Zero Valent Iron ◽

Degradation Pathways ◽

First Order ◽

First Order Kinetics ◽

Degradation Rates ◽

Initial Ph ◽

Pseudo First Order

Abstract Degradation of naproxen (NAP) by persulfate (PS) activated with zero-valent iron (ZVI) was investigated in our study. The NAP in aqueous solution was degraded effectively by the ZVI/PS system and the degradation exhibited a pseudo-first-order kinetics pattern. Both sulfate radical (SO4•−) and hydroxyl radical (HO•) participate in the NAP degradation. The second-order rate constants for NAP reacting with SO4•− and HO• were (5.64 ± 0.73) × 109 M−1 s−1 and (9.05 ± 0.51) × 109 M−1 s−1, respectively. Influence of key parameters (initial pH, PS dosage, ZVI dosage, and NAP dosage) on NAP degradation were evaluated systematically. Based on the detected intermediates, the pathways of NAP degradation in ZVI/PS system was proposed. It was found that the presence of ammonia accelerated the corrosion of ZVI and thus promoted the release of Fe2+, which induced the increased generation of sulfate radicals from PS and promoted the degradation of NAP. Compared to its counterpart without ammonia, the degradation rates of NAP by ZVI/PS were increased to 3.6–17.5 folds and 1.2–2.2 folds under pH 7 and pH 9, respectively.

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Reaction Kinetics of Carbon Dioxide in Aqueous Diethanolamine Solutions Using the Stopped-Flow Technique

Ecological Chemistry and Engineering S ◽

10.2478/v10216-011-0006-y ◽

2012 ◽

Vol 19 (1) ◽

pp. 55-66 ◽

Cited By ~ 5

Author(s):

Marta Siemieniec ◽

Hanna Kierzkowska-Pawlak ◽

Andrzej Chacuk

Keyword(s):

Carbon Dioxide ◽

Reaction Kinetics ◽

Rate Constants ◽

Reaction Rate ◽

Reaction Rate Constant ◽

Stopped Flow ◽

First Order ◽

Pseudo First Order ◽

Kinetics Of ◽

Good Agreement

Reaction Kinetics of Carbon Dioxide in Aqueous Diethanolamine Solutions Using the Stopped-Flow Technique The pseudo-first-order rate constants (kOV) for the reactions between CO2 and diethanolamine have been studied using the stopped-flow technique in an aqueous solution at 293, 298, 303 and 313 K. The amine concentrations ranged from 167 to 500 mol·m-3. The overall reaction rate constant was found to increase with amine concentration and temperature. Both the zwitterion and termolecular mechanisms were applied to correlate the experimentally obtained rate constants. The values of SSE quality index showed a good agreement between the experimental data and the corresponding fit by the use of both mechanisms.

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Pyrolysis Modeling in a Woodstove

Heat Transfer: Volume 3 ◽

10.1115/ht2008-56083 ◽

2008 ◽

Author(s):

Rajesh Gupta

Keyword(s):

Rate Constant ◽

Empirical Model ◽

Reaction Rate ◽

Packed Bed ◽

Reaction Rate Constant ◽

Order Reaction ◽

Pseudo First Order Reaction ◽

First Order ◽

Pseudo First Order ◽

Simple Empirical Model

A simple empirical model for predicting the pyrolysis rate of fuel packed bed of a woodstove has been presented. The thermolytic behavior of the fuel bed has been approximated by a pseudo-first order reaction. The reaction rate constant has been determined as function of temperature. The effect of orientation of twigs in the fuel bed arrangement and twig diameter on the reaction rate constant has been analyzed. It has been concluded that the effect of twig orientation is insignificant while the peak magnitude of reaction rate constant increased with increasing twig diameter.

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Degradation of Orange IV Dye Solution Catalyzed by PVDF/Fe3+-TiO2 Catalytic Membrane in the Presence of H2O2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.150-151.1705 ◽

2010 ◽

Vol 150-151 ◽

pp. 1705-1709

Author(s):

Ying Jie Zhang ◽

Li Zhang ◽

Xiao Fei Ma ◽

Li Li ◽

Jun Ma

Keyword(s):

Reaction Rate ◽

Removal Rate ◽

Sol Gel ◽

Reaction Rate Constant ◽

Catalytic Membrane ◽

Electron Hole ◽

Membrane Area ◽

First Order Kinetics ◽

Initial Ph ◽

Ph Range

A new heterogeneous PVDF/Fe3+-TiO2 catalytic membrane is prepared by sol-gel method, which had a well catalytic activity to decompose H2O2. The effect of initial pH, e initial concentration of H2O2 and Orange IV, temperature, and membrane area on the reaction rate is discussed. The PVDF/Fe3+-TiO2 catalytic membrane can effectively decolorize Orange IV in the pH range of 3.0-5.0. The optimal concentration of H2O2 is 15mmol/L. The reaction rate constant is proportional to the initial concentrations of Orange IV. The higher the temperature, the faster the reaction rate is, this reaction follows pseudo-first-order kinetics with activation energy of 1.54kJ/mol. Reuse of catalyst did not decrease the removal rate of Orange IV. The experiments of t-butanol, EDTA and XPS measurement showed that •OH, the electron hole and the ferryl are all the reactive species in the degradation of Orange IV.

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Photocatalytic Degradation of Erythrosin-B using Cadmium Cobaltite for Water Reuse: Efficiency and Degradation Pathway

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22713 ◽

2020 ◽

Vol 32 (9) ◽

pp. 2143-2148

Author(s):

JAYANTI SAMOTA ◽

SURAJ SHARMA ◽

SHIPRA BHARDWAJ ◽

KUMUD INTODIA

Keyword(s):

Photocatalytic Degradation ◽

Water Reuse ◽

Reaction Rate ◽

Degradation Pathway ◽

Photochemical Degradation ◽

Erythrosin B ◽

First Order ◽

First Order Kinetics ◽

Pseudo First Order ◽

The Impact

In present work, a photocatalytic degradation of Erythrosin-B has been studied using cadmium cobaltite. The impact of different parameters such as pH, amount of cadmium cobaltite, concentration of Erythrosin-B and light intensity have been observed on the reaction rate. Radical quenching experiments revealed that hydroxyl radicals are primarily responsible for the degradation of Erythrosin-B. The progress of reaction monitored spectrophotometrically and it followed pseudo first-order kinetics. An experimental mechanism is proposed for the photochemical degradation of Erythrosin-B.

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Influence of pH on Cadmium Removal from Wastewater by SSI

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.232.935 ◽

2012 ◽

Vol 232 ◽

pp. 935-938

Author(s):

Jun Guo Li ◽

Yan Shi ◽

Na Bi ◽

Yan Ping Feng

Keyword(s):

Reaction Rate ◽

Ph Value ◽

Direct Reduction ◽

Reaction Rate Constant ◽

Cadmium Removal ◽

First Order ◽

Initial Ph ◽

Apparent Reaction Rate Constant ◽

Influence Of Ph ◽

Apparent Reaction Rate

Spherical sponge iron (SSI) with high activity and intension could be prepared through direct reduction by hydrogen. pH value in solution increased despite initial pH because a large amount of H+ was depleted along with erosion battery reaction of SSI. It was suggested that initial pH has significant influence on pH value in solution and cadmium removal percentage by SSI. When the initial pH maintained at 2.03, cadmium removal percentages were only 10.17% and 22.00%, respectively, in 10min and 30min. While the initial pH was adjusted to 3.00, cadmium removal percentage could be elevated to 73.10% and 95.46% in similar libration time. Cadmium removal by SSI appeared to be the first-order reaction. When the initial pH was maintained at 2.03, the apparent reaction rate constant of cadmium removal by SSI was only 0.434 and 1.027 h-1, while which could be elevated to 5.882 and 5.249 h-1 when the initial pH was adjusted to 3.00.

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Degradation and mineralization of violet-3B dye using C-N-codoped TiO2 photocatalyst

Environmental Engineering Research ◽

10.4491/eer.2019.196 ◽

2019 ◽

Vol 25 (4) ◽

pp. 529-535 ◽

Cited By ~ 1

Author(s):

Reza Audina Putri ◽

Safni Safni ◽

Novesar Jamarun ◽

Upita Septiani ◽

Moon-Kyung Kim ◽

...

Keyword(s):

Reaction Rate ◽

Sol Gel ◽

Organic Dye ◽

Halogen Lamp ◽

Acidic Ph ◽

Initial Concentration ◽

First Order ◽

First Order Kinetics ◽

Pseudo First Order ◽

Catalyst Dosage

The present study investigated the photodegradation of synthetic organic dye; violet-3B, without and with the addition of C-N-codoped TiO2 catalyst using a visible halogen-lamp as a light source. The catalyst was synthesized by using a peroxo sol-gel method with free-organic solvent. The effects of initial dye concentration, catalyst dosage, and pH solution on the photodegradation of violet-3B were examined. The efficiency of the photodegradation process for violet-3B dye was higher at neutral to less acidic pH. The kinetics reaction rate of photodegradation of violet-3B dye with the addition of C-N-codoped TiO2 followed pseudo-first order kinetics represented by the Langmuir-Hinshelwood model, and increasing the initial concentration of dyes decreased rate constants of photodegradation. Photodegradation of 5 mg L-1 violet-3B dye achieved 96% color removal within 240 min of irradiation in the presence of C-N-codoped TiO2 catalyst, and approximately 44% TOC was removed as a result of the mineralization.

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Enzymatic Nitrate Assay by a Kinetic Method Employing Escherichia coli Nitrate Reductase

Zeitschrift für Naturforschung C ◽

10.1515/znc-1985-1-226 ◽

1985 ◽

Vol 40 (1-2) ◽

pp. 134-137 ◽

Cited By ~ 4

Author(s):

Johannes Schild ◽

Jobst-Heinrich Klemme

Keyword(s):

Nitrate Reductase ◽

Reaction Rate ◽

Kinetic Method ◽

Test System ◽

Enzymatic Assay ◽

E Coli ◽

First Order ◽

First Order Kinetics ◽

Membrane Bound ◽

Pseudo First Order

Abstract An enzymatic assay system for nitrate employing the membrane-bound nitrate reductase (EC 1.7.99.4) of E. coli is described. Contrary to previous enzymatic assay systems, the present method is a kinetic one, i.e. the substrate, nitrate, is assayed by measuring the reaction rate of the nitrate reductase-catalyzed reaction. Based on the observation that the nitrate reductase-catalyzed reaction obeys pseudo-first order kinetics, a test system is described allowing the assay of nitrate at a concentration as low as 1 ppm. The relatively high M ichaelis-M enten constant for nitrate (0.3 mᴍ) of the E. coli nitrate reductase favours nitrate assay by the kinetic method.

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Electro-photocatalytic degradation of amoxicillin using calcium titanate

Open Chemistry ◽

10.1515/chem-2018-0108 ◽

2018 ◽

Vol 16 (1) ◽

pp. 949-955 ◽

Cited By ~ 3

Author(s):

Lvshan Zhou ◽

Xiaogang Guo ◽

Chuan Lai ◽

Wei Wang

Keyword(s):

Photocatalytic Degradation ◽

Reaction Rate ◽

Irradiation Time ◽

Oxygen Demand ◽

Reaction Rate Constant ◽

Calcium Titanate ◽

Experimental Conditions ◽

Exponential Factor ◽

First Order ◽

First Order Kinetics

AbstractThe electro-photocatalytic degradation of amoxicillin in aqueous solution was investigated using single factor test by the potassium permanganate method for measuring the values of chemical oxygen demand (CODMn). Batch experiments were carried out successfully under different conditions, including initial amoxicillin concentration, calcium titanate dosage, pH, UV irradiation time, electrolyte and temperature. The experimental results show that there is a great difference between electro-photocatalytic and photocatalitic degradation. The maximum electro-photocatalytic degradation efficiency can increase to 79% under the experimental conditions of 200 mL amoxicillin solution (100 mg L-1) with 0.5 g calcium titanate by pH=3 for 120 min irradiation and 0.058 g sodium chloride as electrolyte at 318.5K. In addition, the reaction rate constant of 0.00848~0.01349 min-1, activation energy of 9.8934 kJ mol-1 and the pre-exponential factor of 0.5728 were obtained based on kinetics studies, indicating that the electro-photocatalytic reaction approximately followed the first-order kinetics model.

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