Performance of Modified Graphite Felt as Cathode in the Electro-Fenton System

2020 ◽  
Vol 12 (3) ◽  
pp. 350-356 ◽  
Author(s):  
Dongbao Song ◽  
Junfeng Li ◽  
Weiwei Liu ◽  
Zhaoyang Wang ◽  
Chun Zhao ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Removal Rate ◽  
Electrical Energy ◽  
Degradation Process ◽  
Reaction Rate Constant ◽  
Production Performance ◽  
Impregnation Method ◽  
Application Performance ◽  
Graphite Felt ◽  
Fenton System

The graphite felt (GF) was modified by the impregnation method and the potentiostatic oxidation method to improve its application performance in the electro-Fenton (E-Fenton) system. Sulfuric acid and ammonia water were used as modifying reagents. After the GF was modified, its conductivity, adsorption performance and hydrogen peroxide production performance were improved. The original graphite felt (GF0) and the modified GF were used as cathode to degrade methylene blue in the E-Fenton system to explore the practical application performance. The reaction kinetics of the methylene blue degradation process was fitted. The results showed the degradation of methylene blue followed the first-order kinetics. The GF was modified by the potentiostatic oxidation with ammonia as modifying reagent (GFEN) had the best application performance in the E-Fenton system. Degradation of methylene blue for 30 min, the reaction rate constant of GFEN cathode system was 1.71 times higher than GF0 cathode system. The GFEN electrode was reused 10 times in the E-Fenton system, the removal rate of methylene blue was only decreased by 7.14%, and the current was only decreased by 4 mA, which showed its good stability. Finally, the comparison of the electrical energy per order (EE/O) values showed that GFEN can significantly improve the current efficiency of the E-Fenton system.

scholarly journals Enhancement of Iron-Based Photo-Driven Processes by the Presence of Catechol Moieties

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 372
Author(s):  
Javier Moreno-Andrés ◽  
Iván Vallés ◽  
Paula García-Negueroles ◽  
Lucas Santos-Juanes ◽  
Antonio Arques
Keyword(s):  
Fenton Reaction ◽  
Advanced Oxidation Processes ◽  
Salt Water ◽  
Degradation Process ◽  
Contaminants Of Emerging Concern ◽  
Low Salt ◽  
Aquaculture Industry ◽  
Iron Based ◽  
Ph Range ◽  
Fenton System

Photo-induced Advanced Oxidation Processes (AOPs) using H2O2 or S2O82− as radical precursors were assessed for the abatement of six different contaminants of emerging concern (CECs). In order to increase the efficiency of these AOPs at a wider pH range, the catechol organic functional compound was studied as a potential assistant in photo-driven iron-based processes. Different salinity regimes were also studied (in terms of Cl− concentration), namely low salt water (1 g·L−1) or a salt–water (30 g·L−1) matrix. Results obtained revealed that the presence of catechol could efficiently assist the photo-Fenton system and partly promote the photo-induced S2O82− system, which was highly dependent on salinity. Regarding the behavior of individual CECs, the photo-Fenton reaction was able to enhance the degradation of all six CECs, meanwhile the S2O82−-based process showed a moderate enhancement for acetaminophen, amoxicillin or clofibric acid. Finally, a response-surface methodology was employed to determine the effect of pH and catechol concentration on the different photo-driven processes. Catechol was removed during the degradation process. According to the results obtained, the presence of catechol in organic macromolecules can bring some advantages in water treatment for either freshwater (wastewater) or seawater (maritime or aquaculture industry).

scholarly journals Superior Degradation Performance of Nanoporous Copper Catalysts on Methyl Orange

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 913
Author(s):  
Jinyi Wang ◽  
Sen Yang
Keyword(s):  
Activation Energy ◽  
Methyl Orange ◽  
High Efficiency ◽  
Low Cost ◽  
Degradation Process ◽  
Copper Catalysts ◽  
Reaction Rate Constant ◽  
Nanoporous Structure ◽  
Intra Particle Diffusion ◽  
Different Temperatures

The development of low-cost and high-efficiency catalysts for wastewater treatment is of great significance. Herein, nanoporous Cu/Cu2O catalysts were synthesized from MnCu, MnCuNi, and MnCuAl with similar ligament size through one-step dealloying. Meanwhile, the comparisons of three catalysts in performing methyl orange degradation were investigated. One of the catalysts possessed a degradation efficiency as high as 7.67 mg·g−1·min−1. With good linear fitting by the pseudo-first-order model, the reaction rate constant was evaluated. In order to better understand the degradation process, the adsorption behavior was considered, and it was divided into three stages based on the intra-particle diffusion model. Three different temperatures were applied to explore the activation energy of the degradation. As a photocatalytic agent, the nanoporous structure of Cu/Cu2O possessed a large surface area and it also had low activation energy, which were beneficial to the excellent degradation performance.

scholarly journals Influence of a Surface Finishing Method on Light Collection Behaviour of PWO Scintillator Crystals

Photonics ◽  
2018 ◽  
Vol 5 (4) ◽  
pp. 47 ◽  
Author(s):  
Daniele Rinaldi ◽  
Luigi Montalto ◽  
Michel Lebeau ◽  
Paolo Mengucci
Keyword(s):  
High Energy Physics ◽  
Collection Efficiency ◽  
Removal Rate ◽  
Light Yield ◽  
Grazing Incidence ◽  
Structural Condition ◽  
High Energy ◽  
Production Performance ◽  
Surface Finishing ◽  
Light Collection

In the field of scintillators, high scintillation and light production performance require high-quality crystals. Although the composition and structure of crystals are fundamental in this direction, their ultimate optical performance is strongly dependent on the surface finishing treatment. This paper compares two surface finishing methods in terms of the final structural condition of the surface and the relative light yield performances. The first polishing method is the conventional “Mechanical Diamond Polishing” (MDP) technique. The second polishing technique is a method applied in the electronics industry which is envisaged for finishing the surface treatment of scintillator crystals. This method, named “Chemical Mechanical Polishing” (CMP), is efficient in terms of the cost and material removal rate and is expected to produce low perturbed surface layers, with a possible improvement of the internal reflectivity and, in turn, the light collection efficiency. The two methods have been applied to a lead tungstate PbWO4 (PWO) single crystal due to the wide diffusion of this material in high energy physics (CERN, PANDA project) and diagnostic medical applications. The light yield (LY) values of both the MDP and CMP treated crystals were measured by using the facilities at CERN while their surface structure was investigated by Scanning Electron Microscopy (SEM) and Grazing Incidence X-ray Diffraction (GID). We present here the corresponding optical results and their relationship with the processing conditions and subsurface structure.

Influence Factors of Denitration Study on Catalyst Mn-Ce/TiO2

2013 ◽  
Vol 634-638 ◽  
pp. 526-530
Author(s):  
Chun Xiang Geng ◽  
Qian Qian Chai ◽  
Wei Yao ◽  
Chen Long Wang
Keyword(s):  
Reaction Temperature ◽  
Catalytic Reduction ◽  
Removal Rate ◽  
Load Capacity ◽  
Fixed Bed ◽  
Influence Factors ◽  
Space Velocity ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Ammonia Gas

Selective Catalytic Reduction (SCR) processes have been one of the most widely used denitration methods at present and the property of low tempreture catalyst becomes a hot research. The Mn-Ce/TiO2 catalyst was prepared by incipient impregnation method. The influence of load capacity, reaction temperature, O2 content, etc. on denitration were studied by a fixed bed catalyst reactor with ammonia gas. Results showed that catalyst with load capacity 18% performed high NO removal rate of 90% at conditions of reaction temperature 160°C, low space velocity, NH3/NO molar ratio 1: 1, O2 concentration 6%.

Preparation of Nanosized TiO2-Photocatalyst From-Sludge (TFS) and the Characteristics of Concrete Sidewalk Blocks Using TFS

2021 ◽  
Vol 21 (7) ◽  
pp. 3882-3886
Author(s):  
Yong-Wook Jung ◽  
Jong Kyu Kim
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Degradation ◽  
Air Pollutants ◽  
Removal Rate ◽  
Low Cost ◽  
Sewage Treatment ◽  
Mixing Ratio ◽  
Tio2 Photocatalyst ◽  
And Performance ◽  
Nanosized Tio2

In this study, nano-sized low cost titanium dioxide (TFS) was prepared using sludge from sewage treatment and performance was verified. To remove air pollutants, the photocatalytic degradation of methylene blue and efflorescence characteristics is assessed according to the mixing ratio of the nano-sized TFS by applying them to concrete sidewalk blocks. The photocatalytic degradation performance of concrete sidewalk blocks shows that the methylene blue removal rate of specimens containing 2.5%, 5%, and 10% of nano-sized TFS is 29%, 27%, and 38%, respectively. When the nano-sized TFS is mingled on the surface of the sidewalk block, the performance of anti-corrosion and antifouling showed excellency mainly due to the moisture blocking derived by the antifouling function of photocatalysts.

Iron-Cobalt Magnetic Activated Carbon as an Effective Adsorbent for the Removal of Methylene Blue and Acid Blue 80

NANO ◽  
2021 ◽  
pp. 2150068
Author(s):  
Zhao Yang ◽  
Zhongwei Zhao ◽  
Xuan Yang ◽  
Zongli Ren
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
Organic Dyes ◽  
Removal Rate ◽  
Recovery Process ◽  
Adsorption Activity ◽  
Magnetic Activated Carbon ◽  
Pseudo Second Order ◽  
Repeated Use ◽  
Acid Blue

For the treatment of dye wastewater, it is of great significance to develop new adsorbents with high adsorption capacity and good separation effect. In this study, the Fe-Co magnetic activated carbon material (CN-Fe-Co-AC) was first prepared by high-temperature calcination. CN-Fe-Co-AC is physically characterized by various methods. CN-Fe-Co-AC can efficiently and quickly remove the organic dyes methylene blue (MB) and acid blue 80 (AB80). The adsorption of MB and acid blue based on CN-Fe-Co-AC adsorbent is mainly through the specific surface area and the functional groups on the surface. During this recovery process, the adsorption activity of CN-Fe-Co-AC for MB and AB80 decreased slightly. Kinetic data can be described using a Pseudo-second-order model and the data for adsorption equilibrium can be described using the Langmuir isotherm. The theoretical adsorption capacities of MB and AB80 are 104.82[Formula: see text]mg/g and 26.94[Formula: see text]mg/g, respectively. After repeated use of five times, the removal rate of MB exceeded 96%, and the removal rate of AB80 exceeded 75%. The excellent adsorption performance and recyclability of CN-Fe-Co-AC indicate that this material has certain potential application value.

scholarly journals Electromechanical Dynamics Model of Ultrasonic Transducer in Ultrasonic Machining Based on Equivalent Circuit Approach

Sensors ◽  
2019 ◽  
Vol 19 (6) ◽  
pp. 1405
Author(s):  
Jian-Guo Zhang ◽  
Zhi-Li Long ◽  
Wen-Ju Ma ◽  
Guang-Hao Hu ◽  
Yang-Min Li
Keyword(s):  
Removal Rate ◽  
Ultrasonic Transducer ◽  
Mechanical Vibration ◽  
Electrical Energy ◽  
Structure Design ◽  
Machining Process ◽  
Ultrasonic Machining ◽  
Impedance Model ◽  
Impedance Characteristics ◽  
Electromechanical Dynamics

Ultrasonic transducer is a piezoelectric actuator that converts AC electrical energy into ultrasonic mechanical vibration to accelerate the material removal rate of workpiece in rotary ultrasonic machining (RUM). In this study, an impedance model of the ultrasonic transducer is established by the electromechanical equivalent approach. The impedance model not only facilitates the structure design of the ultrasonic transducer, but also predicts the effects of different mechanical structural dimensions on the impedance characteristics of the ultrasonic transducer. Moreover, the effects of extension length of the machining tool and the tightening torque of the clamping nut on the impedance characteristics of the ultrasonic transducer are investigated. Finally, through experimental analysis, the impedance transfer function with external force is established to analyze the dynamic characteristics of machining process.

Enhanced Biodegradation of Aniline under Anoxic Condition

2011 ◽  
Vol 356-360 ◽  
pp. 25-30 ◽  
Author(s):  
Jin You Shen ◽  
Chao Zhang ◽  
Xiu Yun Sun ◽  
Jian Sheng Li ◽  
Lian Jun Wang
Keyword(s):  
Performance Analysis ◽  
Benzene Ring ◽  
Organic Pollutants ◽  
Degradation Rate ◽  
Removal Rate ◽  
Degradation Process ◽  
Anoxic Condition ◽  
Aerobic Degradation ◽  
Industrial Wastewaters ◽  
Enhanced Biodegradation

Recalcitrant and toxic organic pollutants such as aniline from numerous industrial wastewaters can not be efficiently removed using the conventional methods. This study reported a concept for mineralization of aniline in an anoxic reactor, where enhanced biodegradation of aniline were achieved under anoxic conditions. The results indicated that with the presence of nitrate, the degradation rate of aniline was greatly improved compared with the absence of nitrate. From the UV-vis adsorption spectra, COD analysis and denitrification performance analysis, it could be inferred that the cleavage of benzene ring of aniline occurred, aniline could be mineralization by microorganisms under the anoxic condition. However, aniline removal rate was lower compared to aerobic degradation process, and thus needs a significant improvement.

Modification and adsorption performance of ultrafine iron matrix composite powder

2014 ◽  
Vol 21 (1) ◽  
pp. 39-47
Author(s):  
Li Zhang ◽  
Yao Ding ◽  
Yu-Juan Liu ◽  
Xi Zheng ◽  
Sheng-Li Liu
Keyword(s):  
Methylene Blue ◽  
Matrix Composite ◽  
Composite Powder ◽  
Milling Time ◽  
Removal Rate ◽  
Weight Ratio ◽  
Slurry Concentration ◽  
Adsorption Performance ◽  
Preparation Conditions ◽  
Optimum Parameters

AbstractUltrafine matrix composite powder was prepared from brown corundum slag, grinding balls, anhydrous ethanol, and modifier using a planetary ball mill. The adsorption material was used for dyeing wastewater treatment. A pH instrument, spectrophotometer, and digital water bath oscillator were used to study the amount of modifier, milling speed, milling time, ball-to-powder weight ratio, and slurry concentration to investigate the effects of preparation conditions on the adsorption performance of adsorbent material. The prepared adsorbents and activated carbon were used to adsorb methylene blue in solution under the same conditions to compare adsorbent dosage, adsorption time, temperature, pH of solution, and initial concentration of methylene blue and to study their effects on methylene blue decolorization rate. The experiment results show that dosage of R of 7.5%, ball-to-powder weight ratio of 14:1, rotational speed of 500 rpm, slurry concentration of 20%, and ball milling time of 2.5 h were the optimum parameters. The composite powder (4 g/l) was added to methylene blue wastewater (35 mg/l), pH was adjusted to 6, and adsorption was carried out for 0.5 h at 30°C. The removal rate reached 99.4%.

Sign in / Sign up

Export Citation Format

Share Document