Black clay (BC) was used as a catalyst for the decolorization of Azure B dye by Fenton process. BC was modi ed by acid, alkali, distilled water, and calcination to check their changes in characterization and e ciency ...Black clay (BC) was used as a catalyst for the decolorization of Azure B dye by Fenton process. BC was modi ed by acid, alkali, distilled water, and calcination to check their changes in characterization and e ciency on decolorization of Azure B. Among three modi ed catalysts, maximum decolorization was obtained by acid-modi ed BC (AMBC) catalyst due to the highest removal of impurities, comparatively. The characterization of AMBC was done by Fourier-transform infrared spectroscopy and X-ray di raction spectroscopy which show the presence of metal ion. The BET surface area, pore volume, pore size, and density of AMBC were calculated to be 79.402 m 2 /g, 0.0608 m 3 /g, 0.00306 nm, and 16 g/cm 3 , respectively. The highest decolorization of 97.59% was achieved only in 10 min using AMBC at optimized calcination of 100 °C and 3 h of aging. AMBC was considered as the main catalyst for optimizing the di erent process parameters. Optimized conditions were obtained: pH 2, 0.2 mL of H 2 O 2 , catalyst dose 0.3 g, room temperature (30 °C), and stirring speed 400 r/min. The catalyst has showed excellent stability and reusability. It could remove more than 85% of color even after four cycles of run and less than negligible leaching of iron. AMBC has good recycling ability among other modi ed catalysts. To check the selectivity of catalyst, di erent dyes such as Congo red and mixed dye (mixture of Azure B and Congo red) decolorization were studied. In the present work, kinetic study was also carried out and a three-stage decolorization process was found.展开更多
基金supported by Department of Science & Technology—Science & Engineering Research Board (No. YSS/2014/000996, India)
文摘Black clay (BC) was used as a catalyst for the decolorization of Azure B dye by Fenton process. BC was modi ed by acid, alkali, distilled water, and calcination to check their changes in characterization and e ciency on decolorization of Azure B. Among three modi ed catalysts, maximum decolorization was obtained by acid-modi ed BC (AMBC) catalyst due to the highest removal of impurities, comparatively. The characterization of AMBC was done by Fourier-transform infrared spectroscopy and X-ray di raction spectroscopy which show the presence of metal ion. The BET surface area, pore volume, pore size, and density of AMBC were calculated to be 79.402 m 2 /g, 0.0608 m 3 /g, 0.00306 nm, and 16 g/cm 3 , respectively. The highest decolorization of 97.59% was achieved only in 10 min using AMBC at optimized calcination of 100 °C and 3 h of aging. AMBC was considered as the main catalyst for optimizing the di erent process parameters. Optimized conditions were obtained: pH 2, 0.2 mL of H 2 O 2 , catalyst dose 0.3 g, room temperature (30 °C), and stirring speed 400 r/min. The catalyst has showed excellent stability and reusability. It could remove more than 85% of color even after four cycles of run and less than negligible leaching of iron. AMBC has good recycling ability among other modi ed catalysts. To check the selectivity of catalyst, di erent dyes such as Congo red and mixed dye (mixture of Azure B and Congo red) decolorization were studied. In the present work, kinetic study was also carried out and a three-stage decolorization process was found.
