Batch reactor kinetic studies on the reductive dechlorination of chlorinated ethylenes by tetrakis-(4-sulfonatophenyl)porphyrin cobalt

Abstract Catalytic wet oxidation of high concentration pharmaceutical wastewater with Fe3+ as catalyst was carried out in a batch reactor. Results showed that the degradation of pharmaceutical wastewater was enhanced significantly by Fe3+. The effects of reaction parameters, such as the catalyst dose, reaction temperature, time, and initial oxygen pressure, were discussed. The chemical oxygen demand (COD) removal increased with the increases of catalyst dose, temperature, time and oxygen supply. With the initial COD 34,000–35,000 mg/L, approximately 70% COD removal can be achieved under the conditions of catalyst 1.0 g and oxygen pressure 1.0 MPa at 250 °C after 60 min. The results of kinetic studies showed that two reaction steps existed in this oxidation process, which followed an apparent first-order rate law. This process provides an effective approach for the pretreatment of high concentration pharmaceutical wastewater.

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Evaluation of the Bioelectrochemical Approach and Different Electron Donors for Biological Trichloroethylene Reductive Dichlorination

Toxics ◽

10.3390/toxics10010037 ◽

2022 ◽

Vol 10 (1) ◽

pp. 37

Author(s):

Edoardo Dell’Armi ◽

Marta Maria Rossi ◽

Lucia Taverna ◽

Marco Petrangeli Papini ◽

Marco Zeppilli

Keyword(s):

Reductive Dechlorination ◽

Molecular Hydrogen ◽

Batch Reactor ◽

Electron Donors ◽

Utilization Efficiency ◽

Batch Reactors ◽

Organic Substrates ◽

Chlorinated Aliphatic Hydrocarbons ◽

Low Solubility ◽

Dechlorination Reaction

Trichloroethylene (TCE) and more in general chlorinated aliphatic hydrocarbons (CAHs) can be removed from a contaminated matrix thanks to microorganisms able to perform the reductive dechlorination reaction (RD). Due to the lack of electron donors in the contaminated matrix, CAHs’ reductive dechlorination can be stimulated by fermentable organic substrates, which slowly release molecular hydrogen through their fermentation. In this paper, three different electron donors constituted by lactate, hydrogen, and a biocathode of a bioelectrochemical cell have been studied in TCE dechlorination batch experiments. The batch reactors evaluated in terms of reductive dechlorination rate and utilization efficiency of the electron donor reported that the bio-electrochemical system (BES) showed a lower RD rate with respect of lactate reactor (51 ± 9 µeq/d compared to 98 ± 4 µeq/d), while the direct utilization of molecular hydrogen gave a significantly lower RD rate (19 ± 8 µeq/d), due to hydrogen low solubility in liquid media. The study also gives a comparative evaluation of the different electron donors showing the capability of the bioelectrochemical system to reach comparable efficiencies with a fermentable substrate without the use of other chemicals, 10.7 ± 3.3% for BES with respect of 3.5 ± 0.2% for the lactate-fed batch reactor. This study shows the BES capability of being an alternative at classic remediation approaches.

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3-Chlorophenol Biodegradation in a Sequencing Batch Reactor: Kinetic Study and Effect of the Filling Time

Water Air & Soil Pollution ◽

10.1007/s11270-010-0334-z ◽

2010 ◽

Vol 212 (1-4) ◽

pp. 219-229 ◽

Cited By ~ 5

Author(s):

Agostina Chiavola ◽

Renato Baciocchi ◽

Federico Barducci

Keyword(s):

Kinetic Study ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Filling Time ◽

Reactor Kinetic

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Kinetics of the Ozonation of Tetrabromobisphenol-A in Wastewater

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.2945 ◽

2011 ◽

Vol 383-390 ◽

pp. 2945-2950 ◽

Cited By ~ 1

Author(s):

Jie Zhang ◽

Shi Long He ◽

Mei Feng Hou ◽

Li Ping Wang ◽

Li Jiang Tian

Keyword(s):

Rate Constants ◽

Apparent Rate Constant ◽

Reaction Rate ◽

Batch Reactor ◽

Kinetic Studies ◽

Tetrabromobisphenol A ◽

First Order ◽

Reaction Rate Constants ◽

Pseudo First Order ◽

Kinetics Of

The kinetics of TBBPA degradation by ozonation in semi-batch reactor was studied. The reaction rate constants of TBBPA with O3 and •OH were measured by means of direct ozone attack and competition kinetics, and the values of which were 6.10 l/(mol•s), 4.8×109 l/(mol•s), respectively. Results of kinetic studies showed that TBBPA degradation by ozonation under the different conditions tested followed the pseudo-first-order. The values of apparent rate constant of TBBPA degradation increased with the increase of ozone dosage and pH, but decreased with the increase of initial TBBPA concentration.

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