scholarly journals Taguchi Optimization of Catalytic Ozonation Process Using Modified Bone Char Ash for Removal of Methylene Blue from Aqueous Solution

2020 ◽  
Vol 7 (2) ◽  
pp. 66-71
Author(s):  
Ghorban Asgari ◽  
Somaye Akbari
Keyword(s):  
Methylene Blue ◽  
Reaction Time ◽  
Textile Industry ◽  
Ph Value ◽  
Catalytic Ozonation ◽  
Bone Char ◽  
Operational Parameters ◽  
Taguchi Optimization ◽  
Initial Ph ◽  
Ozonation Process

Methylene blue (MB) dye is an environmental contaminant that has been mostly used in textile industry. Taguchi orthogonal array design was employed as an optimization method to reduce the number of experiments. In this research, bone char ash modified by MgO-Fe catalyst was applied for degradation of MB in catalytic ozonation process (COP) system and operational parameters including initial MB dosages, initial pH, catalyst dose, and contact time were optimized with Taguchi method. Accordingly, the best condition for the removal of MB obtained at initial MB concentration of 20 mg/L, reaction time of 15 minutes, initial pH value of 10, and catalyst concentration of 0.1 g/L. Additionally, optimization of experimental set-up showed that the MB concentration had a notable effect on MB degradation in COP process (55.6%), and reaction time had a negligible effect (1.98%). At this condition, total organic carbon (TOC) removal was determined to be 31% but in longer time, its removal increased to 65%.

Advanced Treatment of Biochemical Treated Coking Wastewater by Ozonation Process

2013 ◽  
Vol 726-731 ◽  
pp. 2515-2520 ◽  
Author(s):  
De Min Yang ◽  
Jian Mei Yuan
Keyword(s):  
Reaction Time ◽  
Reaction Temperature ◽  
Ozone Concentration ◽  
Ph Value ◽  
Removal Rate ◽  
Color Removal ◽  
Advanced Treatment ◽  
Coking Wastewater ◽  
Initial Ph ◽  
Ozonation Process

Advanced treatment of biochemical treated coking wastewater was studied experimentally with ozonation process. The effects of initial pH value, ozone concentration, reaction temperature, and reaction time on the COD and color removal rate were investigated. The results showed that ozonation was an effective method for advanced treatment of biochemical treated coking wastewater. The increasing of initial pH value, ozone concentration, reaction temperature, and reaction time has enhanced the removal rate of COD and color. Meanwhile, the results also revealed that the maximal COD and color removal rate of 69.65% and 92.27% could be reached under the optimal conditions of the initial pH value is 10.5, ozone concentration is 150 mg/L, reaction temperature is 298 K, and reaction time is 30 min.

Enhanced photocatalytic activity of CeO2 using β-cyclodextrin on visible light assisted decoloration of methylene blue

2013 ◽  
Vol 69 (1) ◽  
pp. 113-119 ◽  
Author(s):  
Sakthivel Pitchaimuthu ◽  
Ponnusamy Velusamy
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Inclusion Complexation ◽  
Processing Parameters ◽  
Operational Parameters ◽  
Illumination Time ◽  
Operational Conditions ◽  
Electron Microscopy Analysis ◽  
Initial Ph

An attempt has been made to enhance the photocatalytic activity of CeO2 for visible light assisted decoloration of methylene blue (MB) dye in aqueous solutions by β-cyclodextrin (β-CD). The inclusion complexation patterns between host and guest (i.e., β-CD and MB) have been confirmed with UV–visible spectral data. The interaction between CeO2 and β-CD has also been characterized by field emission scanning electron microscopy analysis. The photocatalytic activity of the catalyst under visible light was investigated by measuring the photodegradation of MB in aqueous solution. The effects of key operational parameters such as initial dye concentration, initial pH, CeO2 concentration as well as illumination time on the decolorization extents were investigated. Among the processing parameters, the pH of the reaction solution played an important role in tuning the photocatalytic activity of CeO2. The maximum photodecoloration rate was achieved at basic pH (pH 11). Under the optimum operational conditions, approximately 99.6% dye removal was achieved within 120 min. The observed results indicate that the decolorization of the MB followed a pseudo-first order kinetics.

scholarly journals The Removal of Methylene Blue Dye from Aqueous Solutions Using Activated and Non-Activated Bentonites

2003 ◽  
Vol 21 (5) ◽  
pp. 451-462 ◽  
Author(s):  
Sameer Al-Asheh ◽  
Fawzi Banat ◽  
Leena Abu-Aitah
Keyword(s):  
Methylene Blue ◽  
Ph Value ◽  
Sodium Dodecyl ◽  
Freundlich Isotherm ◽  
Blue Dye ◽  
Batch Adsorption ◽  
Ionic Surfactant ◽  
Methylene Blue Dye ◽  
X Ray Diffraction ◽  
Initial Ph

An improvement in the adsorption capacity of naturally available bentonite towards water pollutants such as Methylene Blue dye (MBD) is certainly needed. For this purpose, sodium bentonite was activated by two methods: (1) treatment with sodium dodecyl sulphate (SDS) as an ionic surfactant and (2) thermal treatment in an oven operated at 850°C. Batch adsorption tests were carried out on removing MBD from aqueous solution using the above-mentioned bentonites. It was found that the effectiveness of bentonites towards MBD removal was in the following order: thermal-bentonite > SDS-bentonite > natural bentonite. X-Ray diffraction analysis showed that an increase in the microscopic bentonite platelets on treatment with SDS was the reason behind the higher uptake of MBD. An increase in sorbent concentration or initial pH value of the solutions resulted in a greater removal of MBD from the solution. An increase in temperature led to an increase in MBD uptake by the bentonites studied in this work. The Freundlich isotherm model was employed and found to represent the experimental data well.

Effects of operational parameters on defluoridation efficiency using electrocoagulation process

2011 ◽  
Vol 6 (1) ◽  
Author(s):  
M. Behbahani ◽  
M.R. Alavi Moghaddam ◽  
M. Arami
Keyword(s):  
Reaction Time ◽  
Anode Material ◽  
Removal Efficiency ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Operational Parameters ◽  
Applied Current ◽  
Initial Ph ◽  
Electrocoagulation Process ◽  
Electrode Connection

The aim of this study is to examine the effect of operational parameters on fluoride removal using electrocoagulation method. For this purpose, various operational parameters including initial pH, initial fluoride concentration, applied current, reaction time, electrode connection mode, anode material, electrolyte salt, electrolyte concentration, number of electrodes and interelectrode distance were investigated. The highest defluoridation efficiency achieved at initial pH 6. In the case of initial fluoride concentration, maximum removal efficiency (98.5%) obtained at concentration of 25mg/l. The increase of applied current and reaction time improved defluoridation efficiency up to 99%. The difference of fluoride removal efficiencies between monopolar and bipolar series and monopolar parallel were significant, especially at reaction time of 5 min. When aluminum used as anode material, higher removal efficiency (98.5%) achieved compared to that of iron anode (67.7%). The best electrolyte salt was NaCl with the maximum defluoridation efficiency of 98.5% compared to KNO3 and Na2SO4. The increase of NaCl had no effect on defluoridation efficiency. Number of electrodes had little effect on the amounts of Al3+ ions released in the solution and as a result defluoridation efficiency. Almost the same fluoride removal efficiency obtained for different interelectrode distances.

The pretreatment of acrylonitrile and styrene with the ozonation process

1997 ◽  
Vol 36 (2-3) ◽  
pp. 263-270 ◽  
Author(s):  
Cheng-Nan Chang ◽  
Jih-Gaw Lin ◽  
Allen C. Chao ◽  
Bo-Chuan Cho ◽  
Ruey-Fang Yu
Keyword(s):  
Organic Nitrogen ◽  
Ph Value ◽  
Raw Materials ◽  
Removal Rate ◽  
Acrylonitrile Butadiene Styrene ◽  
Ozone Treatment ◽  
Oxidation Reduction ◽  
Initial Ph ◽  
Cod Removal Rate ◽  
Ozonation Process

Acrylonitrile and styrene are used as the raw materials for manufacturing acrylic fiber, thus they are often found as pollutants in the petrochemical wastewater. This study utilizes ozone to decompose the organic nitrogen contained in acrylonitrile and styrene, and the oxidation process was monitored using on-line measurements of oxidation-reduction potential (ORP) and pH. The efficiency of organic nitrogen decomposition was also estimated based on the COD, organic nitrogen, TOC, ammonia-N, nitrite, and nitrate measurements. Both the initial pH and alkalinity are observed to affect the degradation rate of organic nitrogen. The acrylonitrile sample with the lowest initial pH value (i.e., 4.0) has a shorter t1/2 of 18.9 min and that for samples of the highest initial pH (i.e., 11) was 34 min. The alkalinity of one acrylonitrile sample was boosted by adding 500 mg/l CaCO3, to simulate the field ABS (Acrylonitrile-Butadiene-Styrene) wastewater effluent. It was observed that within a short ozone contact time, the acrylonitrile sample spiked with 500 mg/l CaCO3 had the highest COD decomposition rate of 0.411 min−1, or 1.3 times more than that for samples without addition of CaCO3. Results of the ozonation process can be fitted with a modified Nernst equation for the various pH conditions. Additionally, the ozone treated synthetic ABS sample shows a faster COD removal rate in the subsequent biological process than those samples without ozone treatment.

Combined UV catalytic ozonation process on iron loaded peanut shell ash for the removal of methylene blue from aqueous solution

2020 ◽  
Vol 200 ◽  
pp. 231-240
Author(s):  
Amir Ikhlaq ◽  
Farhan Javed ◽  
Ayesha Niaz ◽  
Hafiz Muhammad Shahzad Munir ◽  
Fei Qi
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Catalytic Ozonation ◽  
Peanut Shell ◽  
Ozonation Process

The efficiency and mechanism of γ-alumina catalytic ozonation of 2-methylisoborneol in drinking water

2006 ◽  
Vol 6 (3) ◽  
pp. 43-51 ◽  
Author(s):  
L. Chen ◽  
F. Qi ◽  
B. Xu ◽  
Z. Xu ◽  
J. Shen ◽  
...  
Keyword(s):  
Drinking Water ◽  
Ph Value ◽  
Relative Concentration ◽  
Catalytic Ozonation ◽  
Hydroxyl Group ◽  
Ozone Decomposition ◽  
Group Status ◽  
Remarkable Effect ◽  
Surface Hydroxyl ◽  
Ozonation Process

The efficiency and mechanism in degradation of 2-methylisoborneol (MIB) as a taste and odour compound in drinking water were studied under the condition where γ-alumina catalysed ozonation. As a result, γ-alumina can show distinct activity in enhancing the efficiency of ozonation of MIB. Tert-butyl alcohol had a remarkable effect on the removal efficiency of catalytic ozonation of MIB. The surface charge status, surface hydroxyl group status of γ-alumina, and pH values of the solution can be linked together. When the pH value of the solution was near the pHzpc of γ-Al2O3, there was observable activity in the catalysed ozonation process. Rct, which denoted the relative concentration of hydroxyl radical (·OH), was much higher in the catalysed ozonation process than in the ozonation process. This result further illuminated that γ-Al2O3 can promote ozone decomposition to produce ·OH. Finally, the effect of rP/I on catalysed ozone decomposition and ozone decomposition was investigated.

Oxidative Decolorization of Azo Dyes with Copper Phthalocyanine Supported Mg-Al Hydrotalcites

2016 ◽  
Vol 703 ◽  
pp. 306-310
Author(s):  
Min Hong Xu ◽  
Jian Li Ma ◽  
Meng Xia Qian ◽  
Hui Na Qin
Keyword(s):  
Molecular Structure ◽  
Methylene Blue ◽  
Methyl Orange ◽  
Azo Dyes ◽  
Acidic Solution ◽  
Copper Phthalocyanine ◽  
Ph Value ◽  
Influence Factors ◽  
Amido Black ◽  
Initial Ph

Oxidative decolorization of azo dyes with a heterogeneous catalyst copper phthalocyanine supported Mg-Al hydrotalcites was studied and the influence factors such as initial pH value, temperature, H2O2 and CuPc-LDHs/H2O2 system were discussed. The results indicated that acidic solution and high temperature were conducive to oxidative decoloration of methyl orange. CuPc-LDHs/H2O2 system showed excellent oxidative decoloration capacity to remove azo dyes. The effects of oxidative decolorization of azo dyes were related to the molecular structure and weight of azo dyes. Oxidative decoloration effects followed the order as congo red > amido black > methyl blue> methyl orange> methylene blue.

scholarly journals Complete mineralization of acetic acid using catalytic ozonation with a high energy efficiency enhanced by MnO2/γ-Al2O3

2021 ◽  
Author(s):  
Ruiyun Meng ◽  
Shuiliang Yao ◽  
Erhao Gao ◽  
Zuliang Wu ◽  
Jing Li ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Acetic Acid ◽  
Ph Value ◽  
Acetic Acid Solution ◽  
High Energy ◽  
Catalytic Ozonation ◽  
Acid Oxidation ◽  
Initial Ph ◽  
Catalyst Powder ◽  
Complete Mineralization

Abstract The complete mineralization of acetic acid in a biodegradation process is difficult due to the α-position methyl on the carboxyl group of acetic acid. This study explores the complete oxidation of acetic acid by catalytic ozonation. Metal oxides of MnO2, Co3O4, Fe3O4, and CeO2 loaded on γ-Al2O3 power were used as the catalysts. The experimental results showed that MnO2/γ-Al2O3 catalyst had the best mineralization performance for acetic acid. Typically, the mineralization of acetic acid is as high as 88.4% after 300 min ozonation of 100 mL of 1.0 g L‒1 acetic acid catalysed by 3.0 g 1.0wt.% MnO2/γ-Al2O3 catalyst powder with an energy efficiency of 15 g kWh‒1. However, without a catalyst, the mineralization of acetic acid is only 33.2% with an energy efficiency of 5.1 g kWh−1. The effects of MnO2 loading, catalyst dosage, acetic acid concentration, O3 concentration, ozonation temperature, and initial pH value of the acetic acid solution were systematically investigated. Radical quenchers and in-situ DRIFTS analyses indicated that •OH radical and reactive oxygen species on catalyst surface played an important role in the ozonation of acetic acid to CO2 and H2O. The mechanism of acetic acid oxidation on MnO2/γ-Al2O3 is proposed.

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