scholarly journals Efficient reduction of methylene blue in aqueous solution using a Fenton-like catalyst of Fe3O4/Cu

2021 ◽  
Vol 947 (1) ◽  
pp. 012015
Author(s):  
Huynh-Vu-Thanh Luong ◽  
Huynh-Giao Dang ◽  
Phuong-Lan Tran-Nguyen ◽  
Diem-Trang Phan-Thi ◽  
Lam-Gia-Hao Dao
Keyword(s):  
Methylene Blue ◽  
Contact Time ◽  
Reaction Rate ◽  
Active Oxygen Species ◽  
Reaction Rate Constant ◽  
Active Oxygen ◽  
Oxygen Species ◽  
Optimum Conditions ◽  
Efficient Reduction ◽  
Pseudo Second Order

Abstract This work aimed to investigate the efficient reduction of methylene blue (MB) by a heterogeneous magnetic nanoparticles/copper (MNs/Cu) Fenton-like catalyst. The MNs/Cu was successfully synthesized in the presence of Citrus aurantifolia extract. The characterizations showed an effective fabrication of Cu onto the surface of MNs. The reduction of MB by the MNs/Cu Fenton-like catalyst presented an efficiency of 99.5% at the optimum conditions, including MNs/Cu dose of 0.1 mg, temperature of 25°C, contact time of 75 min, pH 4.0, and 20 mL H2O2 30%, MB initial concentration of 25 mg/L. The reduction kinetics was well fitted to pseudo-second-order with reaction rate constant of 0.0029 g/mg.min. The main mechanism of the MB reduction due to active oxygen species was pointed out. The decrease of reduction yield at high pH, catalyst dose and MB concentration was elucidated in this study.

Removal of Methylene Blue and Orange-G from Waste Water Using Magnetic Biochar

2015 ◽  
Vol 14 (04) ◽  
pp. 1550009 ◽  
Author(s):  
N. M. Mubarak ◽  
Y. T. Fo ◽  
Hikmat Said Al-Salim ◽  
J. N. Sahu ◽  
E. C. Abdullah ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Contact Time ◽  
Agitation Speed ◽  
Adsorption Kinetic ◽  
Maximum Adsorption Capacity ◽  
Optimum Conditions ◽  
Magnetic Biochar ◽  
Design Expert ◽  
Orange G ◽  
Pseudo Second Order

The study on the removal of methylene blue (MB) and orange-G dyes using magnetic biochar derived from the empty fruit bunch (EFB) was carried out. Process parameters such as pH, adsorbent dosage, agitation speed and contact time were optimized using Design-Expert Software v.6.0.8. The statistical analysis reveals that the optimum conditions for the maximum adsorption of MB are at pH 2 and pH 10, dosage 1.0 g, and agitation speed and contact time of 125 rpm and 120 min respectively. While for orange-G, at pH 2, dosage 1.0 g, and agitation speed and contact time of 125 rpm and 120 min respectively. The maximum adsorption capacity of 31.25 mg/g and 32.36 mg/g for MB and orange-G respectively. The adsorption kinetic for both dyes obeyed pseudo-second order.

scholarly journals Molecular Interactions between Methylene Blue and Sodium Alginate Studied by Molecular Orbital Calculations

Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 7029
Author(s):  
Pasika Temeepresertkij ◽  
Michio Iwaoka ◽  
Satoru Iwamori
Keyword(s):  
Methylene Blue ◽  
Sodium Alginate ◽  
Molecular Orbital ◽  
Molecular Interactions ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Molecular Orbital Calculations ◽  
Oxygen Species ◽  
Computational Calculations

A methylene blue (MB) indicator embedded in sodium alginate (SA) film was previously examined for detecting active oxygen species. In a previous study, spectrometry was used to identify and characterize the MB/SA complex. However, the decolorization mechanism was not fully assessed. In this study, our aim is to conduct computational calculations at the B3LYP/6-31G(d) level to clarify the exact types and positions of the interaction that cause the decolorization in MB. The results demonstrate that MB/SA interacts with carboxylates (-COO(superscript)-(superscript)) of SA and the N, C, and S atoms of MB, confirming previous experimental observations.

scholarly journals Study Into Dynamic Behaviour of the Methylene Blue Adsorption on Activated Carbon

2021 ◽  
Vol 29 (48) ◽  
pp. 105-113
Author(s):  
Alica Pastierová ◽  
Maroš Sirotiak
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
Contact Time ◽  
Dynamic Behaviour ◽  
Time Effect ◽  
Adsorption Kinetic ◽  
Optimum Conditions ◽  
Methylene Blue Adsorption ◽  
Initial Concentration ◽  
Pseudo Second Order

Abstract This paper presents a study into dynamic behaviour of the methylene blue adsorption (MB) on activated carbon. Effect of four parameters were studied: effect of the adsorbent dosage, effect of contact time, effect of pH, and effect of the initial concentration of methylene blue. The adsorption kinetic data were modelled using the pseudo-first and pseudo-second orders. Results show that, based on the experimental data, the pseudo-second order could be considered satisfactory. Thermodynamic parameters proved that adsorption of dye was spontaneous owing to increase in temperature and endothermic nature. Taguchi method was applied to determine the optimum conditions for removal of methylene blue by activated carbon. The optimum conditions were found to be pH = 7, contact time 60 min, initial concentration of MB 4 mg/L.

scholarly journals Active oxygen species adsorbed on the catalyst surface and its effect on formaldehyde oxidation over Pt/TiO2 catalysts at room temperature; role of the Pt valence state on this reaction?

RSC Advances ◽  
2018 ◽  
Vol 8 (7) ◽  
pp. 3626-3636 ◽  
Author(s):  
Geo Jong Kim ◽  
Sang Moon Lee ◽  
Sung Chang Hong ◽  
Sung Su Kim
Keyword(s):  
Valence State ◽  
Room Temperature ◽  
Reaction Rate ◽  
Catalyst Surface ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Oxygen Species ◽  
Temperature Oxidation ◽  
Formaldehyde Oxidation

Two catalyst factors were identified that affected the reaction rate in the room temperature oxidation of HCHO.

Characterization and functional properties of new everbearing strawberry (Fragaria x ananasa Duch.) cultivar, ‘Summertiara’ berries

2014 ◽  
Vol 4 (1) ◽  
pp. 1 ◽  
Author(s):  
Takeshi Nagai ◽  
Misuzu Tamai ◽  
Masato Sato ◽  
Yasuhiro Tanoue ◽  
Norihisa Kai ◽  
...  
Keyword(s):  
Vitamin C ◽  
Sensory Evaluation ◽  
Functional Properties ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Antihypertensive Activity ◽  
Oxygen Species ◽  
Total Anthocyanins ◽  
Strawberry Cultivar ◽  
The Stability

Background: In recent years, a new everbearing strawberry cultivar, ‘Summertiara’ was cultivated to supply the strawberries in pre-harvest season from July to October in Japan. For highly research and development of processing of this cultivar, ‘Summertiara’ berries, the objective of this study was to characterize these berries, with relation to chemical parameters, total phenols, total flavonoids, total vitamin C, and total anthocyanins, and was to investigate the solubility and the stability of anthocyanins from the berries. Moreover, the functional properties such as antioxidative activity, active oxygen species scavenging activity, and antihypertensive activity were also evaluated.Methods: Chemical analysis, colour measurement, and sensory evaluation of new everbearing strawberry cultivar, ‘Summertiara’ berries were performed. Next, the solubility of anthocyanins from the berries and stability of these against pH, temperature, and an incandescent lighting were investigated. Moreover, functional properties of the extracts prepared from berries were elucidated using 5 different methods.Results: The contents of water, proteins, lipids, carbohydrates, and ash were the same as those of other cultivar berries. The sugar-acid ratio in the berries was low; these were acidulous. By sensory evaluation, the main factors were vivid red colour, aroma, and acidity. The berries were rich in phenols, flavonoids, vitamin C, and anthocyanins. The anthocyanins of the berries became unstable by heat treatment and light exposures such as visible rays. On the other hand, the extracts prepared from the berries showed the functionalities such as antioxidant activity, active oxygen species scavenging activities, and antihypertensive activity.  Conclusions: The strawberry cultivar, ‘Summertiara’ berries were the most suitable for processing ingredient of strawberry-derived products with superior health promoting functionalities.Keywords: Summertiara, everbearing strawberry cultivar, characterization, sensory evaluation, color and storage, functional property

Identifying the Active Oxygen Species in SnO2 Based Gas Sensing Materials: An Operando IR Spectrsocopy Study

2015 ◽  
Vol 119 (21) ◽  
pp. 11792-11799 ◽  
Author(s):  
David Degler ◽  
Susanne Wicker ◽  
Udo Weimar ◽  
Nicolae Barsan
Keyword(s):  
Gas Sensing ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Oxygen Species ◽  
Ir Spectrsocopy
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