scholarly journals Synergistic effect of sorption and photocatalysis on the degree of dye removal in single and multicomponent systems on ZnO-SnO2

2021 ◽  
Author(s):  
Olga Długosz ◽  
Anita Staroń ◽  
Paulina Brzoza ◽  
Marcin Banach
Keyword(s):  
Dye Removal ◽  
Uv Light ◽  
Ternary Systems ◽  
Industrial Applications ◽  
Degradation Efficiency ◽  
Anionic Dyes ◽  
Photodegradation Efficiency ◽  
Removal Efficiencies ◽  
Positively Charged ◽  
Main Factor

AbstractThe paper presents the photodegradation process of one-, two- and three-component dye mixtures by ZnO-SnO2 nanoparticles. After 60 min of running the processes, the dye removal efficiencies of 76.44, 72.69, 62.43, 77.00 and 92.46% for MB, RB, TB, MO and YQ degradation, respectively, were obtained. For binary and ternary systems, dye removal efficiencies for all cases exceeded 70%. When the binary and ternary dye mixtures were tested, the photodegradation efficiencies of ZnO-SnO2 were similar to those of the single mixtures, indicating that this material could be used in industrial applications in the future. The focus of the study was to investigate the effect of sorption on photodegradation efficiency and the presence of both cationic and anionic dyes on their degradation efficiency under UV light. The significance of the effect of sorption on the degradation efficiency allowing the interaction of the catalyst with the dyes removed was confirmed. The main factor influencing sorption and consequently photocatalysis was the nature of the dye. It was confirmed that the positively charged ZnO-SnO2 surface effectively sorbs the dyes and causes their degradation.

scholarly journals Enhanced Photocatalytic Activity of Spherical Nd3+ Substituted ZnFe2O4 Nanoparticles

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2054
Author(s):  
Loan T. T. Nguyen ◽  
Hang T. T. Nguyen ◽  
Thieng H. Le ◽  
Lan T. H. Nguyen ◽  
Hai Q. Nguyen ◽  
...  
Keyword(s):  
Grain Size ◽  
Photocatalytic Activity ◽  
Dye Removal ◽  
Catalyst Loading ◽  
Separation Mechanism ◽  
Light Radiation ◽  
Efficient Separation ◽  
Oxidant Concentration ◽  
Znfe2o4 Nanoparticles ◽  
Removal Efficiencies

In this study, nanocrystalline ZnNdxFe2−xO4 ferrites with x = 0.0, 0.01, 0.03 and 0.05 were fabricated and used as a catalyst for dye removal potential. The effect of Nd3+ ions substitution on the structural, optical and photo-Fenton activity of ZnNdxFe2−xO4 has been investigated. The addition of Nd3+ ions caused a decrease in the grain size of ferrites, the reduction of the optical bandgap energies and thus could be well exploited for the catalytic study. The photocatalytic activity of the ferrite samples was evaluated by the degradation of Rhodamine B (RhB) in the presence of H2O2 under visible light radiation. The results indicated that the ZnNdxFe2−xO4 samples exhibited higher removal efficiencies than the pure ZnFe2O4 ferrites. The highest degradation efficiency was 98.00%, attained after 210 min using the ZnNd0.03Fe1.97O4 sample. The enhanced photocatalytic activity of the ZnFe2O4 doped with Nd3+ is explained due to the efficient separation mechanism of photoinduced electron and holes. The effect of various factors (H2O2 oxidant concentration and catalyst loading) on the degradation of RhB dye was clarified.

scholarly journals Investigation of Dye Removal Capability of Blast Furnace Slag in Wastewater Treatment

2021 ◽  
Vol 13 (4) ◽  
pp. 1970
Author(s):  
Sara Yasipourtehrani ◽  
Vladimir Strezov ◽  
Tao Kan ◽  
Tim Evans
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Industrial Wastewater ◽  
Dye Removal ◽  
Treatment Time ◽  
Activated Carbons ◽  
Industrial Applications ◽  
Ore Processing ◽  
Pre Treatment ◽  
Furnace Slag

Blast Furnace Slag (BFS) is a by-product of the iron ore processing industry with potential to be used in different industrial applications. In this research, BFS was used to examine its ability for dye removal from wastewater. The efficiency of two types of BFS samples for removal of cationic methylene blue (MB) and acidic methyl orange (MO) dyes was investigated and results found that the optimal conditions for treatment of wastewater were 80 g/L of adsorbent dose and 1 h of treatment time for both dyes. BFS was found to be more effective for removal of the acidic MO dye than the cationic MB dye. Under shorter residence times, the results showed reverse trends with BFS samples removing higher concentrations of MB than MO. The BFS chemistry had additional impacts on the efficiency of dye removal. Higher basicity of BFS had lower dye removal ability for adsorption of acidic dye when applied at smaller concentrations, while for cationic dye when applied at higher concentrations. The results showed that BFS has potential role for pre-treatment of industrial wastewater contaminated with dyes and may contribute to reduced use of more expensive adsorbents, such as activated carbons.

Hybrid Pigments Based on Montmorillonite and Anionic Dyes for Leather Finishing

2021 ◽  
Vol 320 ◽  
pp. 198-203
Author(s):  
Anna Bondaryeva ◽  
Olena Mokrousova ◽  
Olena Okhmat
Keyword(s):  
Maximum Level ◽  
Steric Factor ◽  
Anionic Dyes ◽  
Mineral Particles ◽  
High Level ◽  
Leather Finishing ◽  
Positively Charged ◽  
Sodium Form

The work is focused on obtaining hybrid pigments by adsorption of anionic dyes on positively charged montmorillonite. Modification of the sodium form of montmorillonite by chromium hydroxocomplexes was provided to ensure effective adsorption of anionic dyes on the surface of mineral particles. A high level of adsorption of anionic dyes as a result of steric factor was revealed. It was shown that the adsorption of dyes depended on the pH of the medium and was characterized by a maximum level at pH 4.5 – 6.0. The scheme of obtaining hybrid pigments, which were characterized by good сovering ability, resistance to stratification, especially saturated and intense colour was proposed.

scholarly journals Thermodynamic model for solution behavior and solid-liquid equilibrium in Na-Al(III)-Fe(III)-Cr(III)-Cl-H2O system at 25°C

2018 ◽  
Vol 5 (1) ◽  
pp. 6-16
Author(s):  
Laurent André ◽  
Christomir Christov ◽  
Arnault Lassin ◽  
Mohamed Azaroual
Keyword(s):  
Thermodynamic Model ◽  
Specific Interaction ◽  
Soil Formation ◽  
Ternary Systems ◽  
Industrial Applications ◽  
Mineral Dissolution ◽  
Solution Behavior ◽  
Data Limitations ◽  
Pitzer Formalism ◽  
Solid Liquid

AbstractThe knowledge of the thermodynamic behavior of multicomponent aqueous electrolyte systems is of main interest in geo-, and environmental-sciences. The main objective of this study is the development of a high accuracy thermodynamic model for solution behavior, and highly soluble M(III)Cl3(s) (M= Al, Fe, Cr) minerals solubility in Na-Al(III)-Cr(III)-Fe(III)-Cl-H2O system at 25°C. Comprehensive thermodynamic models that accurately predict aluminium, chromium and iron aqueous chemistry and M(III) mineral solubilities as a function of pH, solution composition and concentration are critical for understanding many important geochemical and environmental processes involving these metals (e.g., mineral dissolution/alteration, rock formation, changes in rock permeability and fluid flow, soil formation, mass transport, toxic M(III) remediation). Such a model would also have many industrial applications (e.g., aluminium, chromium and iron production, and their corrosion, solve scaling problems in geothermal energy and oil production). Comparisons of solubility and activity calculations with the experimental data in binary and ternary systems indicate that model predictions are within the uncertainty of the data. Limitations of the model due to data insufficiencies are discussed. The solubility modeling approach, implemented to the Pitzer specific interaction equations is employed. The resulting parameterization was developed for the geochemical Pitzer formalism based PHREEQC database.

Recovery of silver metal from low concentrated wastewater by photocatalysis

2015 ◽  
Vol 29 (10n11) ◽  
pp. 1540028 ◽  
Author(s):  
Mali Ding ◽  
Jie Han ◽  
Wei Qiu ◽  
Weijun Zhang ◽  
Wei Gao
Keyword(s):  
Electron Microscopy ◽  
Uv Light ◽  
Superior Performance ◽  
Catalyst Loading ◽  
X Ray ◽  
Zno Nanopowder ◽  
Removal Efficiencies ◽  
Concentrated Solution ◽  
Silver Metal ◽  
Scanning Electron

This work studies the photocatalytic activity of zinc oxide ( ZnO ) nanopowder to recover silver ( Ag ) metal from low Ag + concentrated solution under artificial ultraviolet (UV) light. Benchmark titanium dioxide (P25 TiO 2) was used for comparison purpose. Experimental results indicated that ZnO exhibited superior performance for Ag recovery compared to TiO 2. Under optimal catalyst loading, the achieved Ag removal efficiencies were 100% and 99.94% at 0.2 g/L ZnO (1 h) and 2 g/L TiO 2 (2 h), respectively. An induction period at low concentration of TiO 2 (0.1 g/L) was observed and a mechanism was proposed. The photodissolution of ZnO was assessed and proved to be negligible. Recovered pure Ag metal was characterized by X-ray diffractometry (XRD) and scanning electron microscopy (SEM), showing a promising effective Ag recovery technology using ZnO photocatalyst.

scholarly journals Photodegradation of Rhodamine B in Presence of CaO and NiO-CaO Catalysts

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Tobias Kornprobst ◽  
Johann Plank
Keyword(s):  
Visible Light ◽  
Specific Surface ◽  
Surface Area ◽  
Rhodamine B ◽  
Uv Light ◽  
Mechanistic Study ◽  
Light Conditions ◽  
No Adsorption ◽  
Charged Surfaces ◽  
Positively Charged

A CaO catalyst was prepared by mild calcination (650°C) of facilely precipitated Ca(OH)2and compared to an NiO-CaO catalyst obtained from an Ni(OH)2/Ca(OH)2coprecipitate as a precursor. Both catalysts degraded rhodamine B (RB) effectively when exposed to ultraviolet light but exhibited slower degradation under visible light conditions. Under UV light, CaO was more effective than NiO-CaO, while in visible light, the opposite was observed. A mechanistic study revealed no influence of the specific surface area of the catalysts on RB degradation, no adsorption of RB on the positively charged surfaces of the catalysts, and only incomplete degradation of RB. Consequently, both materials represent nonconventional photocatalysts.

Impact of the Harsh Environment on E-Glass Epoxy Composite

2019 ◽  
Author(s):  
Amir Hussain Idrisi ◽  
Abdel-Hamid Ismail Mourad ◽  
Beckry Abdel-Magid ◽  
Mohammad Mozumder ◽  
Yaser Afifi
Keyword(s):  
High Temperature ◽  
Composite Materials ◽  
Oil And Gas ◽  
Epoxy Composite ◽  
Uv Light ◽  
Weight Ratio ◽  
High Strength ◽  
Industrial Applications ◽  
Harsh Environment ◽  
Sustained Loads

Abstract Composite materials are being used in many industrial applications such as automobile, aerospace, marine, oil and gas industries due to their high strength to weight ratio. The long-term effect of sustained loads and environmental factors that include exposure to UV light, temperature, and moisture have been under investigation by many researchers. The major objective of this study is to evaluate the effects of harsh environment (e.g. seawater and high temperature) on the structural properties of E-glass epoxy composite materials. These effects were studied in terms of seawater absorption, permeation of salt and contaminants, chemical and physical bonds at the interface and degradation in mechanical properties. Samples were immersed in seawater at room temperature (23°C), 65°C and 90°C for the duration of 6 months. Results show that seawater absorption increased with immersion time at 23°C and 65°C, whereas the weight of the specimens decreased at 90°C. The moisture causes swelling at 23°C and 65°C and breakdown of chemical bonds between fiber and matrix at 90°C. It is observed that high temperature accelerates the degradation of the E-glass epoxy composite. At 90°C, the tensile strength of E-glass epoxy sharply decreased by 72.92% but no significant change was observed in modulus of elasticity of the composite.

scholarly journals Catalytic Removal of Alizarin Red Using Chromium Manganese Oxide Nanorods: Degradation and Kinetic Studies

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1150
Author(s):  
Muhammad Hamza ◽  
Ataf Ali Altaf ◽  
Samia Kausar ◽  
Shahzad Murtaza ◽  
Nasir Rasool ◽  
...  
Keyword(s):  
Kinetic Model ◽  
Manganese Oxide ◽  
Dye Removal ◽  
Dye Degradation ◽  
Uv Light ◽  
Kinetic Studies ◽  
Research Area ◽  
Alizarin Red ◽  
X Ray ◽  
Catalytic Removal

Dye removal through photocatalytic degradation employing nanomaterials as catalysts is a growing research area. In current studies, photocatalytic alizarin red (AR) dye degradation has been investigated by designing a series of Cr based manganese oxide nanomaterials (MH1–MH5). Synthesized nanomaterials were characterized by powder X-ray diffraction, scanning electron microscopy/energy dispersive x-ray, Brunauer–Emmett–Teller, and photoluminescence techniques and were utilized for photocatalytic AR dye degradation under UV light. AR dye degradation was monitored by UV–visible spectroscopy and percent degradation was studied for the effect of time, catalyst dose, different dye concentrations, and different pH values of dye solution. All the catalysts have shown more than 80% dye degradation exhibiting good catalytic efficiencies for dye removal. The catalytic pathway was analyzed by applying the kinetic model. A pseudo second-order model was found the best fitted kinetic model indicating a chemically-rate controlled mechanism. Values of constant R2 for all the factors studied were close to unity depicting a good correlation between experimental data.

scholarly journals The Decoloration of Anionic and Cationic Dyes Using ZnO and ZnO-Cu2O

Crystals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 229 ◽  
Author(s):  
Jiang Dong Dai ◽  
Luo Gan ◽  
Hai Yan Zhang ◽  
Chun Ming Liu
Keyword(s):  
Ultrasonic Irradiation ◽  
Aluminum Foam ◽  
Depletion Layer ◽  
Cationic Dyes ◽  
Free Electrons ◽  
Anionic Dyes ◽  
Adsorption Ability ◽  
Positively Charged ◽  
Adsorption Capability ◽  
Better Than

ZnO and ZnO-Cu2O were grown on aluminum foam using hydrothermal method. Due to the positively charged sites on the surface, both ZnO and ZnO-Cu2O show higher adsorption capability towards anionic dyes, but poorer adsorption capability towards cationic dyes. The adsorption ability of ZnO-Cu2O is smaller than that of ZnO since there is a depletion layer at the interface. In order to decolorize cationic dyes, ZnO and ZnO-Cu2O are used as sono-catalyst with ultrasonic irradiation. The ZnO-Cu2O is better than ZnO in sono-catalysis decoloration of cationic dyes. This may be due to the enhanced piezoelectricity and electrochemical activity, as the free electrons in ZnO are reduced in the depletion layer.

Sign in / Sign up

Export Citation Format

Share Document