A comparative study between Keggin-type tungstophosphates and tungstosilicates in the oxidation of cyclooctane with hydrogen peroxide

2004 ◽  
Vol 222 (1-2) ◽  
pp. 159-165 ◽  
Author(s):  
M. Salete S. Balula ◽  
Isabel C.M.S. Santos ◽  
Mário M.Q. Simões ◽  
M. Graça P.M.S. Neves ◽  
José A.S. Cavaleiro ◽  
...  
2008 ◽  
Vol 9 (14) ◽  
pp. 2411-2416 ◽  
Author(s):  
Valiollah Mirkhani ◽  
Majid Moghadam ◽  
Shahram Tangestaninejad ◽  
Iraj Mohammadpoor-Baltork ◽  
Nahid Rasouli

2016 ◽  
Vol 6 (9) ◽  
pp. 3271-3278 ◽  
Author(s):  
Tiago A. G. Duarte ◽  
Sónia M. G. Pires ◽  
Isabel C. M. S. Santos ◽  
Mário M. Q. Simões ◽  
M. Graça P. M. S. Neves ◽  
...  

A manganese monosubstituted Keggin-type polyoxometalate was used as a catalyst in the oxidation of recalcitrant organosulfur compounds by hydrogen peroxide at room temperature.


Carbon ◽  
2011 ◽  
Vol 49 (8) ◽  
pp. 2842-2851 ◽  
Author(s):  
M.H.M.T. Assumpção ◽  
R.F.B. De Souza ◽  
D.C. Rascio ◽  
J.C.M. Silva ◽  
M.L. Calegaro ◽  
...  

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Dongzhuang Hou ◽  
Lang Liu ◽  
Qixing Yang ◽  
Bo Zhang ◽  
Huafu Qiu ◽  
...  

Cyanidation is widely used by most gold mine worldwide and will remain prevail in years (or decades) to come, while cyanide is hazardous, toxic pollutants whose presence in wastewater and tailings can seriously affect human and its environment; hence, it is necessary to control these contaminants. The purpose of this study was to examine the effects through the investigation of changes in pH, concentration, and contact time, and the optimal conditions were obtained. It has been proven that the decomposition of cyanide in solution and tailings increased as the alkalinity in the presence of 0.5 g/L Na2S2O5. An increase in H2O2 (30%) concentration (from 1 to 4 mL/L) increased the decomposition in solution, while the effect on removing cyanide was better when pH was 9 than 8 and 10 in tailings. The cyanide in tailings decreased in the first 4 h and increased after 4 h. The effective and economic conditions for maximum decomposition of cyanide from leach tailings are first treated in 0.5 g/L Na2S2O5 at pH 10 for 3 hours and then 2 mL/L H2O2 (30%) is added to the tailings at pH 9 for 4 hours through comparative study. The findings provide the basis to optimize the decomposition of cyanide from gold leaching tailings in mining or backfilling by using the synergetic effect of Na2S2O5 and H2O2.


2013 ◽  
Vol 781-784 ◽  
pp. 219-222
Author(s):  
Qiu Ying Huang ◽  
Bei Bei Dong ◽  
Xiu Cheng Zheng

Dodecatungstophosphoric acid was synthesized and used as catalyst for oxidation of benzaldehyde to benzoic acid with aqueous hydrogen peroxide. The effect of various catalytic reaction parameters including time, temperatures, and the amount of catalyst on the yield of benzoic acid was investigated in details. The results indicated that the as-prepared sample was in the keggin-type structure and the optimal parameters under the reaction conditions were as follows: 0.5 g of catalyst, reacted at 80 C for 5 h.


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