This paper provides evidence for the degradation of organic pollutant by the photo-Fenton complex mechanism. Both the complex oxidation and HO. oxidation mechanisms were verified by p-chlorophenol degradation, UV/Vis ...This paper provides evidence for the degradation of organic pollutant by the photo-Fenton complex mechanism. Both the complex oxidation and HO. oxidation mechanisms were verified by p-chlorophenol degradation, UV/Vis spectra anaylsis, and quantum yield. The hydroxyl radical involved in the photo-Fenton process can also be generated from the decomposition of H2O2, photolysis of Fe^3＋ and degradation of hydrated Fe（Ⅵ）-complex, excepting the traditional Fenton reaction.展开更多
A phenol-degrading microorganism, Rhodococcus sp.RSP8, was used to study the substrate interactions during cell growth on phenol and p-chlorophenol dual substrates. Both phenol and p-chlorophenol could be utilized by ...A phenol-degrading microorganism, Rhodococcus sp.RSP8, was used to study the substrate interactions during cell growth on phenol and p-chlorophenol dual substrates. Both phenol and p-chlorophenol could be utilized by the bacteria as the sole carbon and energy sources. When cells grew on the mixture of phenol and p-chlorophenol, strong substrate interactions were observed. The p-chlorophenol inhibited the degradation of phenol, on the other hand, phenol also inhibited the utilization of p-chlorophenol. The overall cell growth rate depends on the co-actions of phenol and p-chlorophenol. In addition, the cell growth and substrate degradation kinetics of phenol, p-chlorophenol as single and mixed substrates for Rhodococcus sp.RSP8 in batch cultures were also investigated over a wide range of initial phenol concentrations (5-1600 mg.L–1) and initial p-chlorophenol concentrations (5 – 250 mg.L–1). The single-substrate kinetics was described well using the Haldane-type kinetic models, with model constants of μm1 = 0.15 h–1, KS1 = 2.22 mg.L–1 and Ki1 = 245.37 mg.L–1 for cell growth on phenol and of μm2 = 0.0782 h–1, KS2 = 1.30 mg.L–1 and Ki2 = 71.77 mg.L–1, K′i2 = 5480 (mg.L–1)2 for cell growth on p-chlorophenol. Proposed cell growth kinetic model was used to characterize the substrates interactions in the dual substrates system.展开更多
Study on the effects of sonolysis, ozonolysis and US/O3 system on the decomposition of p-chlorophenol in aqueous solutions indicated that in the cases of US/O3 system, individual ozonolysis and sonolysis, the decompos...Study on the effects of sonolysis, ozonolysis and US/O3 system on the decomposition of p-chlorophenol in aqueous solutions indicated that in the cases of US/O3 system, individual ozonolysis and sonolysis, the decomposition rate of p-chlorophenol reached 78.78%, 56.20%, 2.79% after a 16-min reaction while its CODcr (chemical oxygen demand) removal rate was 97.02%, 62.17%, 3.67% after a 120-min reaction. The decomposition reaction of p-chlorophenol follows pseudo-first-order kinetics. The enhancement factors of p-chlorophenol and its CODcr under US/O3 system reached 63% and 237% respectively. The main intermediates during the decomposition include catechol, hydroquinone, p-benzoquinone, phenol, fumaric acid, maleic acid, oxalic acid and formic acid. The decomposition mechanism of p-chlorophenol was also discussed.展开更多
Deep degradation of organic pollutants by sunlight-induced coupled photocatalytic and Fenton (photo-Fenton) reactions is of immense importance for water purification. In this work, we report a novel bifunctional catal...Deep degradation of organic pollutants by sunlight-induced coupled photocatalytic and Fenton (photo-Fenton) reactions is of immense importance for water purification. In this work, we report a novel bifunctional catalyst (Fe-PEI-CN) by codoping graphitic carbon nitride (CN) with polyethyleneimine ethoxylated (PEI) and Fe species, which demonstrated high activity during p-chlorophenol (p-ClPhOH) degradation via H_(2)O_(2) from the photocatalytic process. The relationship between the catalytic efficiency and the structure was explored using diff erent characterization methods. The Fe modification of CN was achieved through Fe-N coordination, which ensured high dispersion of Fe species and strong stability against leaching during liquid- phase reactions. The Fe modification initiated the Fenton reaction by activating H_(2)O_(2) into ·OH radicals for deep degradation of p-ClPhOH. In addition, it eff ectively promoted light absorption and photoelectron-hole (e-h ^(+) ) separation, corresponding to improved photocatalytic activity. On the other hand, PEI could significantly improve the ability of CN to generate H_(2)O_(2) through visible light photocatalysis. The maximum H_(2)O_(2) yield reached up to 102.6 μmol/L, which was 22 times higher than that of primitive CN. The cooperation of photocatalysis and the self-Fenton reaction has led to high-activity mineralizing organic pollutants with strong durability, indicating good potential for practical application in wastewater treatment.展开更多
文摘This paper provides evidence for the degradation of organic pollutant by the photo-Fenton complex mechanism. Both the complex oxidation and HO. oxidation mechanisms were verified by p-chlorophenol degradation, UV/Vis spectra anaylsis, and quantum yield. The hydroxyl radical involved in the photo-Fenton process can also be generated from the decomposition of H2O2, photolysis of Fe^3＋ and degradation of hydrated Fe（Ⅵ）-complex, excepting the traditional Fenton reaction.
文摘A phenol-degrading microorganism, Rhodococcus sp.RSP8, was used to study the substrate interactions during cell growth on phenol and p-chlorophenol dual substrates. Both phenol and p-chlorophenol could be utilized by the bacteria as the sole carbon and energy sources. When cells grew on the mixture of phenol and p-chlorophenol, strong substrate interactions were observed. The p-chlorophenol inhibited the degradation of phenol, on the other hand, phenol also inhibited the utilization of p-chlorophenol. The overall cell growth rate depends on the co-actions of phenol and p-chlorophenol. In addition, the cell growth and substrate degradation kinetics of phenol, p-chlorophenol as single and mixed substrates for Rhodococcus sp.RSP8 in batch cultures were also investigated over a wide range of initial phenol concentrations (5-1600 mg.L–1) and initial p-chlorophenol concentrations (5 – 250 mg.L–1). The single-substrate kinetics was described well using the Haldane-type kinetic models, with model constants of μm1 = 0.15 h–1, KS1 = 2.22 mg.L–1 and Ki1 = 245.37 mg.L–1 for cell growth on phenol and of μm2 = 0.0782 h–1, KS2 = 1.30 mg.L–1 and Ki2 = 71.77 mg.L–1, K′i2 = 5480 (mg.L–1)2 for cell growth on p-chlorophenol. Proposed cell growth kinetic model was used to characterize the substrates interactions in the dual substrates system.
文摘Study on the effects of sonolysis, ozonolysis and US/O3 system on the decomposition of p-chlorophenol in aqueous solutions indicated that in the cases of US/O3 system, individual ozonolysis and sonolysis, the decomposition rate of p-chlorophenol reached 78.78%, 56.20%, 2.79% after a 16-min reaction while its CODcr (chemical oxygen demand) removal rate was 97.02%, 62.17%, 3.67% after a 120-min reaction. The decomposition reaction of p-chlorophenol follows pseudo-first-order kinetics. The enhancement factors of p-chlorophenol and its CODcr under US/O3 system reached 63% and 237% respectively. The main intermediates during the decomposition include catechol, hydroquinone, p-benzoquinone, phenol, fumaric acid, maleic acid, oxalic acid and formic acid. The decomposition mechanism of p-chlorophenol was also discussed.
基金the National Key Research and Development Program of China (No. 2020YFA0211004)Key Grant of Nation Science Funding of China (No. 22236005)+5 种基金Nation Science Funding of China (No. 22376141)Ministry of Education of China (No. PCSIRT_IRT_16R49)“111” Innovation and Talent Recruitment Base (D18020)Shanghai Government (No. 20ZR1440700)Shanghai Engineering Research Center of Green Energy Chemical Engineering (No. 18DZ2254200)Scientific and Technological Innovation Team for Green Catalysis and Energy Materialien Yunnan Institutions of Higher Learning, and Surface project of Yunnan Province science and technology Department (No. 20210 A070001-050).
文摘Deep degradation of organic pollutants by sunlight-induced coupled photocatalytic and Fenton (photo-Fenton) reactions is of immense importance for water purification. In this work, we report a novel bifunctional catalyst (Fe-PEI-CN) by codoping graphitic carbon nitride (CN) with polyethyleneimine ethoxylated (PEI) and Fe species, which demonstrated high activity during p-chlorophenol (p-ClPhOH) degradation via H_(2)O_(2) from the photocatalytic process. The relationship between the catalytic efficiency and the structure was explored using diff erent characterization methods. The Fe modification of CN was achieved through Fe-N coordination, which ensured high dispersion of Fe species and strong stability against leaching during liquid- phase reactions. The Fe modification initiated the Fenton reaction by activating H_(2)O_(2) into ·OH radicals for deep degradation of p-ClPhOH. In addition, it eff ectively promoted light absorption and photoelectron-hole (e-h ^(+) ) separation, corresponding to improved photocatalytic activity. On the other hand, PEI could significantly improve the ability of CN to generate H_(2)O_(2) through visible light photocatalysis. The maximum H_(2)O_(2) yield reached up to 102.6 μmol/L, which was 22 times higher than that of primitive CN. The cooperation of photocatalysis and the self-Fenton reaction has led to high-activity mineralizing organic pollutants with strong durability, indicating good potential for practical application in wastewater treatment.
