Kinetics of Pumice Catalyzed Ozonation of Trace p-Chloronitrobenzene in Aqueous Solution

2011 ◽  
Vol 90-93 ◽  
pp. 2925-2928 ◽  
Author(s):  
Lei Yuan ◽  
Ji Min Shen ◽  
Zhong Lin Chen
Keyword(s):  
Aqueous Solution ◽  
Rate Constant ◽  
Butyl Alcohol ◽  
Order Kinetic ◽  
First Order ◽  
Highly Active ◽  
Tert Butyl Alcohol ◽  
Initial Ph ◽  
Order Kinetic Model ◽  
Kinetics Of

The kinetics of pumice for decomposition of p-chloronitrobenzene (pCNB) in aqueous solution were investigate. The experiment result indicated that ozonation alone and pumice-catalyzed ozonation of trace pCNB in aqueous solution followed the Pseudo-first-order kinetic model at the reaction temperature of 296 K and the initial pH of 6.86. The rate constant of pumice-catalyzed ozonation increase 149% compared with ozonation alone. In two processes mentioned above, the rate constants of degradation of pCNB were found to decrease with increasing of tert-butyl alcohol. The rate constant of ozonation alone appeared to be decreased 73%, respectively, decreasing 194% in the process of pumice-catalyzed ozonation. Under the conditions of this experiment, ozonation alone and pumice-catalyzed ozonation for degradation of pCNB were primarily oxidized by highly active hydroxyl radicals.

scholarly journals Decolorization Kinetics of Acid Azo Dye and Basic Thiazine Dye in Aqueous Solution by UV/H2O2 and UV/Fenton: Effects of Operational Parameters

2017 ◽  
Vol 17 (1) ◽  
pp. 85-94
Author(s):  
Ayda Baffoun ◽  
Amel El Ghali ◽  
Imen Hachani
Keyword(s):  
Order Kinetic ◽  
Operational Parameters ◽  
Operational Conditions ◽  
First Order ◽  
Aqueous Effluents ◽  
Initial Ph ◽  
Order Kinetic Model ◽  
Thiazine Dye ◽  
Kinetics Of ◽  
Decolorization Kinetics

AbstractThe photochemical decolorization of two dyes, namely Acid Yellow 54 and Basic Blue 9, was studied using the UV/H2O2and UV/Fenton processes. The effects of the amount of H2O2and FeSO4as well as the initial pH solution on decolorization kinetics of both the dyes were investigated. The pseudo-first order kinetic model was applied to predict the decolorization of the selected dyes at the different operational conditions and results showed that this model fitted very well with the experimental data. The obtained results also showed the efficiency of UV/Fenton process to quickly degrade aqueous effluents polluted by Acid Yellow 54 and Basic Blue 9 compared to the UV/H2O2process.

Kinetics of bioactive compounds in functional spice Jiangpo during thermal processing

2012 ◽  
Vol 8 (3) ◽  
Author(s):  
Xiaoyan Dai ◽  
Chenhuan Yu ◽  
Qiaofeng Wu
Keyword(s):  
Kinetic Parameters ◽  
Bioactive Compounds ◽  
Thermal Processing ◽  
Order Rate Constant ◽  
Heat Processing ◽  
Order Kinetic ◽  
Time Intervals ◽  
First Order ◽  
Order Kinetic Model ◽  
Kinetics Of

Abstract Jiangpo is an increasingly popular East Asian spice which is made from Mangnolia officinalis bark and ginger juice. Since it induces bioactive compounds decomposition and has influence on final flavor and fragrance, cooking is regarded as the key operation in preparation of Jiangpo. To evaluate the bioactive compounds content changes of Jiangpo during thermal processing, kinetic parameters including reaction order, rate constant, T1/2 and activation energy of bioactive markers namely honokiol, magnolol and curcumin were determined. Cooking was set at temperatures 60, 90 and 120 °C for selected time intervals. Results displayed the thermal kinetic characteristics of the three compounds. Thermal degradation of Honokiol and magnolol both followed first order kinetic model and the loss of curcumin fitted second order. A mathematical model based on the obtained kinetic parameters has also been developed to predict the degradation of honokiol, magnolol and curcumin in non-isothermal state. All the information in this paper could contribute necessary information for optimizing the existing heat processing of Jiangpo.

Performance of poly-o-phenylenediamine and its carbon dot composite electrode in the removal of Cu2+ from its aqueous solution

2021 ◽  
pp. 2151037
Author(s):  
Yu Meng ◽  
Qing Zhong ◽  
Arzugul Muslim
Keyword(s):  
Aqueous Solution ◽  
Electrochemical Reduction ◽  
Composite Electrode ◽  
Reduction Process ◽  
Order Kinetic ◽  
Carbon Dot ◽  
First Order ◽  
Oxidation Reduction ◽  
Order Kinetic Model ◽  
Optimal Ph

Because −NH2 and −NH− in poly-[Formula: see text]-phenylenediamine (P[Formula: see text]PD) can interact strongly with the empty orbitals of Cu to show unique electrochemical activity, P[Formula: see text]PD is suitable for the removal of Cu[Formula: see text] by electrochemical oxidation–reduction process. In this study, with P[Formula: see text]PD and its carbon dot composite (CDs/P[Formula: see text]PD) as working electrodes, the electrochemical reduction and removal of Cu[Formula: see text] in the aqueous solution were carried out with the potentiostatic method. According to effects of voltage, pH of the solution, initial concentration of Cu[Formula: see text], and electrochemical reduction time on the Cu[Formula: see text] removal, the Cu[Formula: see text] removal ratios of P[Formula: see text]PD and CDs/P[Formula: see text]PD were up to 64.69% and 73.34%, respectively, at −0.2 V and the optimal pH. Additionally, results showed that these processes were in line with the quasi-first order kinetic model. Both P[Formula: see text]PD and CDs/P[Formula: see text]PD showed good reproducibility in six cycles. After five times of repeated usage, the regeneration efficiencies of P[Formula: see text]PD and CDs/P[Formula: see text]PD dropped to 77.04% and 79.36%, respectively.

Adsorption of Chromium (VI) from Aqueous Solution by Agricultural Waste Derived Activated Carbon

2013 ◽  
Vol 726-731 ◽  
pp. 2100-2106 ◽  
Author(s):  
Hua Zhang ◽  
Xue Hong Zhang ◽  
Yi Nian Zhu ◽  
Shou Rui Yuan
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Agricultural Waste ◽  
Order Kinetic ◽  
Chromium Vi ◽  
Initial Ph ◽  
Order Kinetic Model ◽  
Grapefruit Peel ◽  
Pseudo Second Order ◽  
C 30

Activated carbon prepared from grapefruit peel, an agricultural solid waste by-product, has been used for the adsorption of Cr(VI) from aqueous solution. The effects of adsorbent dosage, pH and temperature on adsorption of Cr(VI) were investigated. The maximum adsorption yield was obtained at the initial pH of 3. The dynamical data fit very well with the pseudo-second-order kinetic model and the calculated adsorption capacities (23.98, 24.33 and 24.81 mg/g) were in good agreement with experiment results at 20°C, 30°C and 40 °C for the 100 mg/L Cr(VI) solution. The Freundlich model (R2 values were 0.9198-0.9871) fitted adsorption data better than the Langmuir model. The calculated parameters confirmed the favorable adsorption of Cr(VI) on the activated carbon prepared from grapefruit peel.

scholarly journals EFFECT OF DIATOMEAOUS EARTH TREATMENT USING HYDROGEN CHLORIDE AND SULFURIC ACID ON KINETICS OF CADMIUM(II) ADSORPTION

2010 ◽  
Vol 2 (2) ◽  
pp. 107-112
Author(s):  
Nuryono Nuryono ◽  
Narsito Narsito
Keyword(s):  
Aqueous Solution ◽  
Sulfuric Acid ◽  
Hydrogen Chloride ◽  
Rate Constant ◽  
Diatomaceous Earth ◽  
Adsorption Rate ◽  
Physical Interaction ◽  
First Order ◽  
Adsorption Rate Constant ◽  
Kinetics Of

In this research, treatment of diatomaceous earth, Sangiran, Central Java using hydrogen chloride (HCl) and sulfuric acid (H2SO4) on kinetics of Cd(II) adsorption in aqueous solution has been carried out. The work was conducted by mixing an amount of grounded diatomaceous earth (200 mesh in size) with HCl or H2SO4 solution in various concentrations for two hours at temperature range of 100 - 150oC. The mixture was then filtered and washed with water until the filtrate pH is approximately 7 and then the residue was dried for four hours at a temperature of 70oC. The product was used as an adsorbent to adsorb Cd(II) in aqueous solution with various concentrations. The Cd(II) adsorbed was determined by analyzing the rest of Cd(II) in the solution using atomic absorption spectrophotometry. The effect of treatment was evaluated from kinetic parameter of adsorption rate constant calculated based on the simple kinetic model. Results showed  that before equilibrium condition reached, adsorpstion of Cd(II) occurred through two steps, i.e. a step tends to follow a reaction of irreversible first order  (step I) followed by reaction of reversible first order (step II). Treatment with acids, either hydrogen chloride or sulfuric acid, decreased adsorption rate constant for the step I from 15.2/min to a range of 6.4 - 9.4/min.  However, increasing concentration of acid (in a range of concentration investigated) did not give significant and constant change of adsorption rate constant. For step II process,  adsorption involved physical interaction with the sufficient low adsorption energy (in a range of 311.3 - 1001 J/mol).     Keywords: adsorption, cdmium, diatomaceous earth, kinetics.

Biosorption of hexavalent chromium from aqueous solution by polyethyleneimine-modified ultrasonic-assisted acid hydrochar from Sargassum horneri

2020 ◽  
Vol 81 (6) ◽  
pp. 1114-1129 ◽  
Author(s):  
Jun Wang ◽  
Qinglong Xie ◽  
Ao Li ◽  
Xuejun Liu ◽  
Fengwen Yu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Batch Adsorption ◽  
Crosslinking Reaction ◽  
Order Kinetic ◽  
Adsorption Capacities ◽  
Initial Ph ◽  
Ultrasonic Assisted ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Abstract In this study, an efficient route to synthesizing polyethyleneimine-modified ultrasonic-assisted acid hydrochar (PEI-USAH) is developed and reported. Ultrasonic irradiation technique was used as surface modification method to shorten the crosslinking reaction for hydrochar and polyethyleneimine (PEI). The PEI-USAH showed an excellent adsorption capacity for Cr(VI) from aqueous solution. The physicochemical properties of this PEI-modified adsorbent were comparatively characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis and CNHS analysis. The effects of contact time, initial pH, and biosorbent dose on adsorption capacities were investigated. The batch adsorption experiments showed that PEI-USAH possessed the maximum adsorption capacities of 94.38 mg/g and 330.84 mg/g for initial Cr(VI) concentration of 100 mg/L and 500 mg/L, respectively. Furthermore, this adsorption process could be fitted to Langmuir adsorption and described by the pseudo second order kinetic model. Based on the above findings, PEI-USAH could be used as a potential adsorbent for removal of Cr(VI) from wastewater.

THE DECOMPOSITION OF SILYL PEROXIDES

1964 ◽  
Vol 42 (5) ◽  
pp. 985-989 ◽  
Author(s):  
Richard R. Hiatt
Keyword(s):  
Thermal Decomposition ◽  
Rate Constant ◽  
Half Life ◽  
Order Rate Constant ◽  
Butyl Alcohol ◽  
Base Catalysis ◽  
First Order ◽  
Tert Butyl ◽  
Tert Butyl Alcohol ◽  
Acid And Base

The thermal decomposition of tert-butyl trimethylsilyl peroxide has been investigated and found to be sensitive to acid and base catalysis and to the nature of the solvent. In heptane and iso-octane the first-order rate constant could be expressed as 1.09 × 1015e−41200/RT and in 1-octene as 3.90 × 1015e−41200/RT (sec−1). The half life at 203 °C was about 1 hour. The reaction was faster in aromatic solvents; in chlorobenzene it was complicated by formation of HCl from the solvent.Products of the reaction were acetone, tert-butyl alcohol and hexamethyldisiloxane.

Radicals induced from peroxomonosulfate by nanoscale zero-valent copper in the acidic solution

2016 ◽  
Vol 74 (8) ◽  
pp. 1946-1952 ◽  
Author(s):  
Peng Zhou ◽  
Bei Liu ◽  
Jing Zhang ◽  
Yongli Zhang ◽  
Gucheng Zhang ◽  
...  
Keyword(s):  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Acidic Solution ◽  
Butyl Alcohol ◽  
First Order ◽  
First Order Kinetics ◽  
Tert Butyl Alcohol ◽  
Initial Ph ◽  
Reactive Radicals ◽  
Reactive Oxidant

A highly efficient advanced oxidation process for the degradation of benzoic acid (BA) during activation of peroxomonosulfate (PMS) by nanoscale zero-valent copper (nZVC) in acidic solution is reported. BA degradation was almost completely achieved after 10 min in the nZVC/PMS process at initial pH 3.0. PMS could accelerate the corrosion of nZVC in acidic to release Cu+ which can further activate PMS to produce reactive radicals. Both sulfate radical (SO4−•) and hydroxyl radical (•OH) were considered as the primary reactive oxidant in the nZVC/PMS process with the experiments of methyl (MA) and tert-butyl alcohol quenching. Acidic condition (initial pH ≤ 3.0) facilitated BA degradation and pH is a decisive factor to affect the oxidation capacity in the nZVC/PMS process. Moreover, BA degradation in the nZVC/PMS process followed the pseudo-first-order kinetics, and BA degradation efficiency increased with the increase of the nZVC dosage.

scholarly journals Stability of tetracycline residues in honey

2012 ◽  
Vol 77 (7) ◽  
pp. 879-886 ◽  
Author(s):  
Cara Cristina ◽  
Dumitrel Gabriela-Alina ◽  
Glevitzky Mirel ◽  
Perju Delia
Keyword(s):  
Life Time ◽  
Order Kinetic ◽  
First Order ◽  
Reaction Rate Constants ◽  
Veterinary Medicines ◽  
West Region ◽  
Tetracycline Degradation ◽  
Order Kinetic Model ◽  
Tetracycline Residues ◽  
Kinetics Of

The problem of availability of veterinary medicines to treat honeybees is discussed extensively worldwide. An uncontrolled administration of antibiotics may lead to contamination of beehive products and contributes to the problem of food safety. In this study, the kinetics of tetracycline (TC) degradation in honey was studied for samples provided by four sideline beekeepers located in the west region of Romania. The samples of honey were stored in the dark at room temperature for 30 days and subsamples were analyzed every 3 days by Elisa method. The results of the study revealed that the level of tetracycline decreases in time for all honey samples. The tetracycline degradation follows a first-order kinetic model with reaction rate constants between 1.2?10-3 - 2?10-3 days-1. The half-life time of tetracycline in monofloral honeys: acacia and lime was 251 and 232 days respectively. Tetracycline degradation in polyfloral honey was accelerated since ?1/2 of TC was 151 days.

Sign in / Sign up

Export Citation Format

Share Document