In this study, the authors have investigated the effects of various factors on both aerobic and anaerobic degradation of 4-t-octylphenol （4-t-OP） in granular sludge. In comparison, the aerobic degradation rate was m...In this study, the authors have investigated the effects of various factors on both aerobic and anaerobic degradation of 4-t-octylphenol （4-t-OP） in granular sludge. In comparison, the aerobic degradation rate was much higher than that of anaerobic degradation. The optimal pH values for 4-t-OP degradation in granular sludge were 9 and 7 under aerobic and anaerobic conditions, respectively. And the degradation rate decreased with an increase in the initial 4-t-OP concentration. Addition of yeast extract or homologous compounds such as phenol also enhanced the 4-t-OP degradation, especially under the aerobic condition. To investigate the bacterial community in this study, the denaturing gradient gel electrophoresis （DGGE） method was applied, based on the primers, for the 16S rDNA V3 region of bacteria, γ-proteobacteria and bacillus were identified as the major species of sludge.展开更多
A spiral photoreactor system （SPS） was developed for the degradation of 4-tert-octylphenol （4-t-OP） in aqueous phase. 4-t-OP was previously considered as a endocrine disrupting compound frequently present in water...A spiral photoreactor system （SPS） was developed for the degradation of 4-tert-octylphenol （4-t-OP） in aqueous phase. 4-t-OP was previously considered as a endocrine disrupting compound frequently present in water. The direct photodegradation reaction caused by the SPS was found to accord with the characteristic of apparent first-order reaction with reaction rate constant k = 4.8 x 10-2 min-1. However, the direct photodegradation reaction could not make the 4-t-OP mineralized. The photodegradation efficiency increased from 88% to 91.2% in 45 min irradiation period after the internal surface of SPS was sintered with TiO2 thin film as catalyst. Catalyst concentration, number of catalyst coating layers and initial concentration of 4-t-OP were proven to be the factors affecting the photocatalytic degradation performance of the SPS on aqueous 4-t-OP. The degradation mechanism was investigated and the byproducts were analyzed using total organic carbon analyzer （TOC） and LC-MS. The possible chemical structures of the products were suggested. SPS with single layer of TiO2 prepared by sintering 13.6% of TiO2 precursor was proven to be more efficient than most of previous systems for removal of 4-t-OP from aqueous phase. 28.3% of the 4-t-OP was mineralized in 45 min according to the decreased amount of TOC value.展开更多
In this study, we have investigated the degradation and primary radiolytic degradation mechanism of 4-tert-octylphenol (4-t-OP) by using of electron beam (EB) -irradiation. The results show that at an absorbed dose of...In this study, we have investigated the degradation and primary radiolytic degradation mechanism of 4-tert-octylphenol (4-t-OP) by using of electron beam (EB) -irradiation. The results show that at an absorbed dose of 10 kGy and an initial concentration of 25 mg·L -1 , the degradation of 4-t-OP in a methanol/water reduction system is higher than in a acetonitrile/water oxidation system by 19.4% and higher than in an acetone/water system by 26.8%, which is due to both of ·OH and e aq - playing an important role in the decomposition of 4-t-OP, although the latter is more effective. The degradation rate of 4-t-OP will decrease with increment of absorbed dose in a methanol/water solution, and increase with decrement of initial concentration at a constant absorbed dose. The degradation efficiency will also decrease with the addition of anions and H 2 O 2 into the solution. A system saturated with N 2 will make an increment in the degradation of 4-t-OP. The pH value of solution has been also found to affect the degradation efficiency, while the degradation is more efficient in alkaline conditions. Finally, the initial products involved in degradation reaction have been determined to be ethylbenzene, styrene, bicyclo[4.2.0]octa-1,3,5-triene, 2,2,4-trimethylpentane and p-tert-butyl-phenol, which may arise from e aq - attack at the position of the alkyl side chain of 4-t-OP molecule. The results have been revealed that EB irradiation is a promising method for degradation of 4-t-OP, and e aq - may be main reactive species to attack at the position of the alkyl side chain of 4-t-OP.展开更多
4-tert-octylphenol (OP) is environmental pollutants that have been shown widespread impact estrogenic and toxic to the cells of mammals in culture. The effects of OP on the reproductive system of adult male vertebrate...4-tert-octylphenol (OP) is environmental pollutants that have been shown widespread impact estrogenic and toxic to the cells of mammals in culture. The effects of OP on the reproductive system of adult male vertebrates especially humans are virtually unknown. Thus, in the present investigation, pregnant females of albino rats were orally treated during pregnancy and until 21 days after birth (the period of lactation) with octylphenol (OP) at doses 0 (vehicle: corn oil), 40 mg/kg and 120 mg/kg on the epididymis of male rats at puberty (12 weeks of age). The present result showed that there is non-significant in the number;the size of newborn rats and there increased in mortality rate of newborn rats of the pregnant female treatment with dose low-and high-octylphenol compared to the control group. there is increased in the average body weight and percentage of gain in body weight of male rats from mothers of small treatment (G2, G3) and the control group (G1) for 12 weeks of age. Also, histological results showed that the adrenal gland in the group which was given high dose of octylphenol (G3) show that Severe histological changes in the cortex. When examining medulla and found large areas of necrosis and cell degradation, necrosis and cell death sharply.展开更多
文摘In this study, the authors have investigated the effects of various factors on both aerobic and anaerobic degradation of 4-t-octylphenol （4-t-OP） in granular sludge. In comparison, the aerobic degradation rate was much higher than that of anaerobic degradation. The optimal pH values for 4-t-OP degradation in granular sludge were 9 and 7 under aerobic and anaerobic conditions, respectively. And the degradation rate decreased with an increase in the initial 4-t-OP concentration. Addition of yeast extract or homologous compounds such as phenol also enhanced the 4-t-OP degradation, especially under the aerobic condition. To investigate the bacterial community in this study, the denaturing gradient gel electrophoresis （DGGE） method was applied, based on the primers, for the 16S rDNA V3 region of bacteria, γ-proteobacteria and bacillus were identified as the major species of sludge.
基金supported by the National Natural Science Foundation of China(No.20777012,21077027 40503011)the Research Fund for the Doctoral Program of Higher Education of China(No.200802460006)the Innovative Foundation of Fudan University
文摘A spiral photoreactor system （SPS） was developed for the degradation of 4-tert-octylphenol （4-t-OP） in aqueous phase. 4-t-OP was previously considered as a endocrine disrupting compound frequently present in water. The direct photodegradation reaction caused by the SPS was found to accord with the characteristic of apparent first-order reaction with reaction rate constant k = 4.8 x 10-2 min-1. However, the direct photodegradation reaction could not make the 4-t-OP mineralized. The photodegradation efficiency increased from 88% to 91.2% in 45 min irradiation period after the internal surface of SPS was sintered with TiO2 thin film as catalyst. Catalyst concentration, number of catalyst coating layers and initial concentration of 4-t-OP were proven to be the factors affecting the photocatalytic degradation performance of the SPS on aqueous 4-t-OP. The degradation mechanism was investigated and the byproducts were analyzed using total organic carbon analyzer （TOC） and LC-MS. The possible chemical structures of the products were suggested. SPS with single layer of TiO2 prepared by sintering 13.6% of TiO2 precursor was proven to be more efficient than most of previous systems for removal of 4-t-OP from aqueous phase. 28.3% of the 4-t-OP was mineralized in 45 min according to the decreased amount of TOC value.
基金Supported by National Natural Science Foundation of China(no.11025526,11175112 and 41073073)
文摘In this study, we have investigated the degradation and primary radiolytic degradation mechanism of 4-tert-octylphenol (4-t-OP) by using of electron beam (EB) -irradiation. The results show that at an absorbed dose of 10 kGy and an initial concentration of 25 mg·L -1 , the degradation of 4-t-OP in a methanol/water reduction system is higher than in a acetonitrile/water oxidation system by 19.4% and higher than in an acetone/water system by 26.8%, which is due to both of ·OH and e aq - playing an important role in the decomposition of 4-t-OP, although the latter is more effective. The degradation rate of 4-t-OP will decrease with increment of absorbed dose in a methanol/water solution, and increase with decrement of initial concentration at a constant absorbed dose. The degradation efficiency will also decrease with the addition of anions and H 2 O 2 into the solution. A system saturated with N 2 will make an increment in the degradation of 4-t-OP. The pH value of solution has been also found to affect the degradation efficiency, while the degradation is more efficient in alkaline conditions. Finally, the initial products involved in degradation reaction have been determined to be ethylbenzene, styrene, bicyclo[4.2.0]octa-1,3,5-triene, 2,2,4-trimethylpentane and p-tert-butyl-phenol, which may arise from e aq - attack at the position of the alkyl side chain of 4-t-OP molecule. The results have been revealed that EB irradiation is a promising method for degradation of 4-t-OP, and e aq - may be main reactive species to attack at the position of the alkyl side chain of 4-t-OP.
文摘4-tert-octylphenol (OP) is environmental pollutants that have been shown widespread impact estrogenic and toxic to the cells of mammals in culture. The effects of OP on the reproductive system of adult male vertebrates especially humans are virtually unknown. Thus, in the present investigation, pregnant females of albino rats were orally treated during pregnancy and until 21 days after birth (the period of lactation) with octylphenol (OP) at doses 0 (vehicle: corn oil), 40 mg/kg and 120 mg/kg on the epididymis of male rats at puberty (12 weeks of age). The present result showed that there is non-significant in the number;the size of newborn rats and there increased in mortality rate of newborn rats of the pregnant female treatment with dose low-and high-octylphenol compared to the control group. there is increased in the average body weight and percentage of gain in body weight of male rats from mothers of small treatment (G2, G3) and the control group (G1) for 12 weeks of age. Also, histological results showed that the adrenal gland in the group which was given high dose of octylphenol (G3) show that Severe histological changes in the cortex. When examining medulla and found large areas of necrosis and cell degradation, necrosis and cell death sharply.
