MANGANESE DIOXIDE IN THE CATALYTIC OXIDATION OF CARBON MONOXIDE1

1923 ◽  
Vol 45 (12) ◽  
pp. 2841-2851 ◽  
Author(s):  
W. A. Whitesell ◽  
J. C. W. Frazer
2019 ◽  
Vol 466 ◽  
pp. 441-453 ◽  
Author(s):  
Lei Miao ◽  
Jinlong Wang ◽  
Pengyi Zhang

2021 ◽  
Vol 5 (1) ◽  
pp. 20-28
Author(s):  
Jorge Luis Mendoza Bobadilla ◽  
Adolfo Enrique Guerrero Escobedo ◽  
Walter Moreno Eustaquio ◽  
Marina Ponce Zavaleta ◽  
Luisa Carbajo Arteaga

The residual effluents from the fur stage of the bovine leather tannery industry are characterized by having a high concentration of sulfides. The objective of this study was to evaluate the effects of aeration time and pH in the residual effluents of the leather stage of the tannery, with the catalysts MnO2 and MnSO4 separately; as well as, determine adjustment models through the response surface methodology and the optimal intervals of the best conditions that lead to a higher percentage of sulfide removal. For this reason, the sulphide removal percentage was evaluated from samples extracted from the pellet stage, by means of catalytic oxidation treatments; varying the catalyst, pH and aeration time. The catalysts used were manganese dioxide (MnO2) and manganese sulfate (MnSO4) and for each catalyst the pH was varied in the values ​​of 8.5; 9.5; 10.2 and 13.4; likewise, the aeration time was varied in the values ​​of 30, 60, 90, 120, 150, 180, 210 and 240 minutes. 64 treatments were carried out, with 3 repetitions each, reporting the average values ​​of the sulfide removal percentage. The response surface methodology was used to adjust the correlation of the variables to a quadratic model; Likewise, through contour graphs the regions with the highest percentage of sulfide removal were easily identified and by superimposing contour graphs the optimal ranges of the variables pH and aeration time were determined for removal percentages greater than 98%. Based on this evaluation, it is proposed for treatments with manganese dioxide, aeration times between 160 to 240 min and pH between 8.5 to 9 and for treatments with manganese sulfate, aeration times between 110 to 240 min and pH between 8.5 to 9.8. The coefficients of multiple determination R2 for the models with catalyst MnO2 and MnSO4 were 97.51% and 95.12% respectively. With the MnSO4 catalyst, higher removal percentages were achieved at a shorter aeration time, compared to the treatments carried out with the MnO2 catalyst.


The Analyst ◽  
1987 ◽  
Vol 112 (9) ◽  
pp. 1339
Author(s):  
V. Chandramouli ◽  
Ram Briksha Yadav

2013 ◽  
Vol 671-674 ◽  
pp. 2769-2772 ◽  
Author(s):  
Min Zhao ◽  
Ji Hui Jiang ◽  
Li Hui Zhou ◽  
Peng Kang Jin ◽  
Dong He

Though analysis and determination on wastewater quality of Gas Field, it can be seen that the main organic matter in wastewater is low concentration methanol. Aiming at the characteristics of higher degree of mineralization, methanol and lower pH ,the experiment is focusing on the effect of manganese dioxide & hydrogen peroxide catalytic oxidation process on methanol wastewater treatment properties and functions.The results show, for low concentration methanol wastewater,the manganese dioxide used has a diameter of 5nm with a dosage of 300mg/L, also a illumination intensity of 120Q, when the dosing ratio with hydrogen peroxide is 1:10, after 8h reaction period, the degradation rate of methanol were all above 70.0%.The methanol content after treated can meet the reference standard for Gas Field reinjection water


2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Thu-Huong Le ◽  
Thu Hong Anh Ngo ◽  
Van Thuan Doan ◽  
Le Minh Tri Nguyen ◽  
Manh Cuong Le

The laterite-coating manganese dioxide nanoparticle material (M2) prepared by the immersion method was used for the efficient removal of methylene blue (MB) from aqueous solution. The adsorption and heterogeneous Fenton catalytic oxidation experiments of M2 were investigated by changing the effective factors such as time, pH, amount of M2, and concentration of MB. The adsorption data of M2 showed good fitting with the Langmuir isotherm, suggesting that the adsorption of MB on the surface of M2 is a heterogeneous and physical adsorption process. Degradation of MB was also carried out to evaluate the heterogeneous Fenton catalytic oxidation characterization of a new catalytic oxidation material (M2). The results show that the M2 material has both adsorption and heterogeneous Fenton catalytic oxidation. However, the heterogeneous Fenton catalytic oxidation of the M2 material is the main performance. Hence, our groups have investigated the ability of the catalytic column treatment with high efficiency of 98–100% and the degradation efficiency after the sample running through the column almost does not change much. This proves that heterogeneous Fenton catalytic activity of the catalytic column is completely unaffected and reused many times after oxidizing MB. Specifically, even if the M2 material is reused for five times, the degradation efficiency still reaches 98.86%.


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