scholarly journals Preparation of Mn/Mg/Ce Ternary Ozone Catalyst and Its Mechanism for the Degradation of Printing and Dyeing Wastewater

2022 ◽  
Vol 9 ◽  
Author(s):  
Shuai Zhang ◽  
Huixue Ren ◽  
Kaifang Fu ◽  
Wenqing Cheng ◽  
Daoji Wu ◽  
...  

The printing and dyeing wastewater produced by different dyes, as well as different printing and dyeing processes, have different components. These wastewater have high toxicity, high organic concentration, and deep chromaticity. Ozone catalytic oxidation is a very promising technical method for wastewater treatment. In this paper, Mn/Mg/Ce ternary catalyst was prepared, and the ozone catalytic oxidation treatment of actual and simulated printing and dyeing wastewater was performed to study the performance of four different carrier catalysts, namely, molecular sieve (MS), silica gel (SG), attapulgite (ATP), and nano alumina (Al2O3), by simulated dynamic test. The effects of reaction time, pH, and catalyst dosage on methyl orange degradation were studied. The results showed that under the optimum treatment conditions (120 min, pH 11, and 12.5 g/L catalyst dosage), the degradation rate of methyl orange reached 96% and the removal rate of the chemical oxygen demand of printing and dyeing wastewater reached 48.7%. This study shows that the treatment effect of ozone catalytic oxidation on printing and dyeing wastewater is remarkably improved after catalyst addition. This study provides a new choice of ozone catalyst for the degradation of printing and dyeing wastewaters in the future.

2019 ◽  
Vol 80 (8) ◽  
pp. 1562-1570
Author(s):  
Shiguo Gu ◽  
Fei Lian ◽  
Kejun Yan ◽  
Wei Zhang

Abstract Polymeric ferric sulfate (PFS) was pretreated with a self-made alternating frequency magnetic field for coagulation printing and dyeing (PD) wastewater treatment. The effects of PFS dosage, magnetization intensity, frequency, and time on the removal of chemical oxygen demand (COD), color and turbidity of PD wastewater were investigated. The results indicated that the magnetized PFS significantly improved the removal efficiency in wastewater treatment. When the initial COD, color and turbidity of printing and dyeing wastewater was 464 mg/L, 180 degrees, and 54.8 NTU respectively, the maximum removal rate of COD, color and turbidity was 87.9%, 80.1%, and 95.2% respectively, under the condition of cross frequency magnetic field magnetization PFS. Moreover, the PFS treatment combined with cross-frequency magnetic field could greatly reduce the pollution of iron ions released from iron-based coagulant during wastewater treatment. Characterization of magnetized PFS flocculant by fourier transform infrared spectroscopy, ultraviolet and visible spectrophotometry, and scanning electron microscopy suggested that magnetic crystal with larger size can be formed on the surface of PFS particles.


2018 ◽  
Vol 2017 (3) ◽  
pp. 707-717 ◽  
Author(s):  
Yan Wang ◽  
Xianwei Wu ◽  
Ju Yi ◽  
Lijun Chen ◽  
Tianxiang Lan ◽  
...  

Abstract A novel iron-carbon (Fe/C) micro-electrolysis combined with H2O2 (ICMH) process was proposed to pretreat the printing and dyeing wastewater (PDW), using a micro-electrolysis filling. The effects of H2O2 concentration, reaction time, initial pH, and Fe/C dosage on chemical oxygen demand (COD) removal rate of PDW were optimized by response surface methodology (RSM). The maximum COD removal rate was approximately 77.65% after 186 min treatment, when the concentration of H2O2, initial pH and the dosage of Fe/C were 8.88 g/L, 1.5 and 837 g/L, respectively. Analysis of variance (ANOVA) showed a high coefficient of determination value (R2 = 0.9780). And H2O2 concentration and initial pH were the key factors to improve the treatment effect. UV-Vis spectra indicated that a significant blue shift at 220 nm, attributing that fused aromatic hydrocarbons were degraded effectively. 3D-EEM spectra analysis showed that the water samples of PDW mainly contained three kinds of organic matter: refractory fulvic acid, soluble microbial metabolites and aromatic proteins, and the degradation rate of these was 81.76%, 53.78% and 70.83%, respectively.


2020 ◽  
Vol 49 (1) ◽  
pp. 46-54 ◽  
Author(s):  
Wei Zhang ◽  
Weiwei Lv ◽  
Xiaoyan Li ◽  
Jiming Yao

Purpose In this study, the oxidative degradation performance of indigo wastewater based on electrochemical systems was explored. The decolourization degrees, removal rate of chemical oxygen demand and biochemical oxygen demand of the indigo wastewater after degradation were evaluated and optimized treatment conditions being obtained. Design/methodology/approach The single factor method was first used to select the electrolyte system and electrode materials. Then the response surface analysis based on Box–Behnken Design was chosen to determine the influence of four independent variables such as FeCl3 concentration, NaCl concentration, decolourization time and voltage on the degradation efficiency. Findings On the basis of single factor experiment, the electrode material of stainless steel was selected in the double cell, and the indigo wastewater was electrolyzed with FeCl3 and NaCl electrolytes. The process conditions of electrochemical degradation of indigo wastewater were optimized by response surface analysis: the concentration of FeCl3 and NaCl was of 16 and 9 g/L, respectively, with a decolourization time of 50 min, voltage of 10 V and decolourization percentage of 98.94. The maximum removal rate of chemical oxygen demand reached 75.46 per cent. The highest ratio of B/C was 3.77, which was considered to be more biodegradable. Research limitations/implications Dyeing wastewater is bringing out more and more pollution problems to the environment. However, there are some shortcomings in traditional technologies such as adsorption and filtration. As a kind of efficient and clean water treatment technology, electrochemical oxidation has been applied to the treatments of various types of wastewater. The decolourization and degradation of indigo wastewater is taken as an example to provide reference for the treatment of wastewater in actual plants. Practical implications The developed method provided a simple and practical solution for efficiently degrading indigo wastewater. Originality/value The method for the electrochemical oxidation technology was novel and could find numerous applications in the degradation of printing and dyeing wastewater.


2016 ◽  
Vol 87 (1) ◽  
pp. 102-109 ◽  
Author(s):  
Chunyan Ma ◽  
Xiaoqian Wu ◽  
Zhenhong Liu

Filtration performance and fouling behavior of a five-bore hollow fiber membrane was investigated in a membrane bioreactor (MBR) treating printing and dyeing wastewater. A normal single-bore hollow fiber membrane module was used in the same bioreactor for comparison. During an operation over 30 days, the results of chemical oxygen demand (COD) and color removals demonstrated that the five-bore membrane was favorable for this wastewater treatment. The critical flux ( Jc) of the five-bore membrane and the single-bore membrane was determined at 21 and 15 L/(m2·h), respectively, using a flux-step method. During a steady running at sub-critical flux of 10 L/(m2·h) without cleaning for 50 days, the average increasing rates of trans-membrane pressure (TMP) for five-bore and single-bore membranes were 0.356 kPa/d and 0.444 kPa/d, respectively, indicating that the five-bore membrane had better fouling resistance. The total resistance values of five-bore membrane and single-bore membrane were 8.68 and 14.1 m−1, respectively. Scanning electron microscope (SEM) and atomic force microscope (AFM) results confirmed the cake layer resistance for five-bore membrane was much lower than single-bore membrane. It was expected that the membrane structure, especially the membrane diameter, influenced the anti-fouling property of five-bore membrane.


2011 ◽  
Vol 71-78 ◽  
pp. 3075-3078
Author(s):  
Ai Hua Gao ◽  
Shui Jiao Yang ◽  
Shang Bin Hu ◽  
Xiao Qing He ◽  
Zhi Guo Lu

The treatment of industrial wastewaters collected from petrochemical works, gypsum plant, and printing and dyeing mill, was investigated at atmospheric pressure in air discharge plasma. The degradation effects of organic contaminants in water were compared for the printing and dyeing wastewater under different discharging conditions and for the wastewater from the other two plants under the same discharging conditions. The influences of several factors on chemical oxygen demand (COD) remove rate were studied experimentally. The results showed that the treatment effects for the same industrial wastewater differed significant under different discharge conditions. There may be a suitable discharge plasma treatment to specific industrial wastewater. Due to the removal rates of COD of industrial wastewaters with discharge plasma isn’t very high, therefore the discharge plasma water treating needs to combine conventional water treating methods or addition other catalyst to effectively remove organic pollutants in wastewater and obtain the expected treatment effect.


2011 ◽  
Vol 415-417 ◽  
pp. 438-441
Author(s):  
Jin Xia Yan ◽  
Dong Fang Li ◽  
Shao Feng Dong

The printing and dyeing wastewater was treated by internal electrolysis method. The results show the chromaticity removal rate was up to 98.53 percent and COD removal rate 85.98 percent under the optimum conditions of wastewater pH 4, reaction time 30 minutes, the electric conductivity 1450μm/cm, the value BOD5/COD increases from 0.34 to 0.51. Moreover, the pH, Fe2+ concentration and absorbance of wastewater changed in the process, the mechanism of that was also analyzed.


2011 ◽  
Vol 71-78 ◽  
pp. 2689-2694 ◽  
Author(s):  
Wen Song Chen ◽  
Hua Shi Lin ◽  
Shuo Feng Zhang

Treatment of printing and dyeing wastewater by the device of high gradient magnetic separation (HGMS) developed by author was tested. The results showed that printing and dyeing wastewater contained varied chemical composition and whose initial concentration of chromaticity and COD were 800 and 565mg/L respectively can be well cleaned by Fenton oxidation—magnetic seed coagulation—HGMS. The removal rate of chromaticity and COD was up to 92.6% and 79.5% respectively. The effluent can meet the national drainage criterion. The optimum technological parameters are as follows: pH=6, [FeSO4·7H2O]=250mg/L, [H2O2]=1.3ml/L, [PAM]=0.75 mg/L, dose of magnetic particle W=150mg/L,current intensity I=8A, current velocity U=2.420L/min, packing density of stainless steel wire R=1.00%-1.43%. Recovery rate of magnetic particle was up to 90% by regenerated technique of chemistry in combination with physics.


2013 ◽  
Vol 467 ◽  
pp. 133-137
Author(s):  
Yong Li Zhang ◽  
Yan Ling Shun

Catalytic Wet Air Oxidation (CWAO) is one of advanced oxidation methods about organic wastewater treatment, and the treatment effect of high concentration organic wastewater is remarkable with this method. In this study, the influence factors of the reaction temperature, the reaction pressure and the influent pH were researched on the treatment of the printing and dyeing wastewater with Cu-Fe-La/FSC catalyst, by the single factor experiments and Catalytic Wet Air Oxidation (CWAO) method. Then the catalysts were evaluated by two aspects of the activity and stability. The results show that: with the increase of the reaction temperatures and the reaction pressures, and with the decrease of the influent pH, the CODCrremoval rate improved and the effluent pH reduced. However, the amount of dissolution catalyst components increased with the improvement of treatment effect and the extension of reaction time. By weighing the activity and stability of the catalysts, the optimized reaction temperature, the reaction pressure and the influent pH are 180 °C, 2.5 MPa and 7.25, respectively. Under the optimized operating conditions, the printing and dyeing wastewater with CODCrof 2000 mg/L reaches the CODCrremoval rate of 78.2%, and the dissolvedC[Cu] andC[Fe] of the catalysts are 12.2 and 10.9 mg/L, respectively. Therefore, the catalyst Cu-Fe-La/FSC presents the high activity and stability.


2020 ◽  
Vol 82 (4) ◽  
pp. 695-703
Author(s):  
Amel Ounnar ◽  
Abdelkrim Bouzaza ◽  
Lidia Favier ◽  
Fatiha Bentahar

Abstract The current work investigates the removal of two hazardous macrolide molecules, spiramycin and tylosin, by photodegradation under external UV-light irradiation conditions in a slurry photoreactor using titanium dioxide as a catalyst. The kinetics of degradation and effects of main process parameters such as catalyst dosage, initial macrolide concentration, light intensity and stirring rate on the degradation rate of pollutants have been examined in detail in order to obtain the optimum operational conditions. It was found that the process followed a pseudo first-order kinetics according to the Langmuir–Hinshelwood model. The optimum conditions for the degradation of spiramycin and tylosin were low compound concentration, 1 g L−1 of catalyst dosage, 100 W m−2 light intensity and 560 rpm stirring rate. Then, a maximum removal (more than 90%) was obtained after 300 min of irradiation time. Furthermore, results show that the selection of optimized operational parameters leads to satisfactory total organic carbon removal rate (up to 51%) and biochemical oxygen demand to chemical oxygen demand ratio (∼1) confirming the good potential of this technique to remove complex macrolides from aqueous solutions.


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