Photocatalytic Degradation of Methylene Blue Using Nano-ZnO at Air Lift Circulating Reactor

Nano-ZnO powder were prepared through gel-sol method with zinc acetate and lithium hydroxide as crude material. Nano-ZnO was analyzed by XRD, SEM, TEM, UV-Vis and determined photocatalytic activity at photocatalytic reactor. The results show that nano-ZnO has a integrate crystal and its size is 6.6nm with the best photocatalytic performance, when calcined at 350oC. The best ZnO dosage is 0.1g/L with 97% Methylene Blue removal after 30min. Compared with different photocatalytic reactor, the airlift reactor is obviously better than bubbling reactor and stirring reactor.

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Nano-ZnO Photocatalytic Kinetics Based on Photo-Layer Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.550-553.2819 ◽

2012 ◽

Vol 550-553 ◽

pp. 2819-2823

Author(s):

Hang Xu ◽

Min Yue Li

Keyword(s):

Methylene Blue ◽

Photocatalytic Performance ◽

Photocatalytic Process ◽

Layer Model ◽

Nano Zno ◽

Photo Catalyst ◽

Zno Powders ◽

Control Step ◽

Air Lift ◽

Crude Material

Nano-ZnO powders were prepared through gel-sol method with zinc acetate and lithium hydroxide as crude material. Nano-ZnO, as photo-catalyst, was used to decompose Methylene Blue at air lift circulating reactor and Photo-Layer model to describe photocatalytic kinetics. The results show that nano-ZnO has a integrate crystal and its size is 6.6nm with the best photocatalytic performance, when calcined at 350oC. The best ZnO dosage is 0.1g/L with 97% Methylene Blue removal after 30min. The photocatalytic process was the control step in chemical reaction. The •OH concentration inside the photo-layer in different reaction condition were calculated according to Photo-Layer model.

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Preparation of Nano-ZnO by Paralled Flaw Precipitation Method under Ultrasonic and their Photocatalytic Performance

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.953-954.999 ◽

2014 ◽

Vol 953-954 ◽

pp. 999-1002

Author(s):

Qing Ming Meng ◽

Jian Wang ◽

Bao Dong Zhu ◽

Jian Wei Zhang ◽

Yuan Yuan Wang

Keyword(s):

Methylene Blue ◽

Photocatalytic Performance ◽

Raw Materials ◽

Average Diameter ◽

Precipitation Method ◽

Methylene Blue Solution ◽

Uniform Size ◽

Nano Zno ◽

Crystal Property ◽

Blue Solution

Nano-ZnO with high photocatalytic performance was prepared by paralled flaw precipitation method under ultrasonic radiation with Zn(NO3)2·6H2O and NH3·H2O as raw materials. The prepared samples were characterized by XRD, SEM and TG/DTA. The decolorization of methylene blue solution as model reaction, the effect of calcining temperature on the structure and photocatalytic performance of the samples were investigated. The results show that nano-ZnO with well crystal property and uniform size distribution, prepared by calcining the precursor at 300 °C for 2 h, had the average diameter of about 38 nm. When 100 mL methylene blue solution with 10 mg/L of mass concentration is treated with the nano-ZnO photocatalyst for 60 min, the decolorizing efficiency of the methylene blue solution reached 62.5 %.

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Relationship between Planes of Cu2O Microcrystal and Photo-Catalytic Degradation of Methylene Blue

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.807-809.562 ◽

2013 ◽

Vol 807-809 ◽

pp. 562-566

Author(s):

Wei Dong Shi ◽

Dan Yan ◽

Wei Qiang Fan

Keyword(s):

Methylene Blue ◽

Photocatalytic Degradation ◽

Diffuse Reflectance ◽

Photocatalytic Performance ◽

Xenon Lamp ◽

X Ray Diffraction ◽

Co Catalyst ◽

X Ray ◽

Main Influence ◽

Better Than

Four kinds of Cu2O microcrystals with different morphologies are synthesized via low temperature hydrothermal synthetic method. The photocatalytic degradation of methylene blue (MB) of the above different Cu2O is preliminary explored based on this observation. 6-facet, 8-facet, 14-facet are prepared by PVP system and 26-facet is prepared by NaOH system. They are characterized by means of Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Diffuse Reflectance Spectra (DRS). Under 150 W xenon lamp irradiation, 0.5 gL1 catalyst and 0.1% (v/v) 30% H2O2 as co-catalyst are used to degrade 5% 100 mL MB solution. The reaction time is 80 min. 26-facet Cu2O polyhedral discolor about 89.48% of MB while 6-facet Cu2O microcrystal about discolor about 20.18% which is the lowest decolourization rate among all the samples. The photocatalytic performance of 8-facet Cu2O microcrystal is slight better than that of 14-facet. The decolourization rate of 8-facet and 14-facet are 56.00% and 41.08%, respectively. The main reason is that the planes of Cu2O microcrystal have a main influence on photocatalytic degradation of MB.

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