Effect of UV Intensity and Wavelengh on Photocatalytic Degradation of Polycyclic Aromatic Hydrocarbons

2011 ◽  
Vol 233-235 ◽  
pp. 466-469
Author(s):  
Li Hong Zhang ◽  
Cheng Bin Xu ◽  
Zhong Lin Chen ◽  
Xue Mei Li

The photocatalytic degradation of pyrene (PYRE) and benzo[a]pyrene (BaP) on soil surfaces in the presence of Fe2O3 using ultraviolet (UV) light source was investigated in a photo chamber, in which the temperature was maintained 30 . The effects of UV irradiation intensity and UV wavelength on the degradation performance of polycyclic aromatic hydrocarbons (PAHs) were studied. The results show that with the intensity of UV irradiation being enhanced, the photocatalytic degradation rates of PAHs were increased. Photocatalytic degradation rates of PYRE and BaP on soil surfaces with 5% Fe2O3 were different at UV irradiation wavelengths of 254, 310 and 365 nm, respectively.

2011 ◽  
Vol 189-193 ◽  
pp. 420-423 ◽  
Author(s):  
Li Hong Zhang ◽  
Nan Jia ◽  
Cheng Bin Xu ◽  
Xue Mei Li

The photocatalytic degradation of phenanthrene (PHE), pyrene (PYRE) and benzo[a]pyrene (BaP) on soil surfaces in the presence of Fe2O3 using ultraviolet (UV) light source was investigated. The effects of various factors, namely Fe2O3, soil pH, and humic acid, on the degradation performance of polycyclic aromatic hydrocarbons (PAHs) were studied. The results show that photocatalytic degradation of PAHs follows the pseudo-first-order kinetics. Catalyst Fe2O3 accelerated the photodegradation of PHE, PYRE and BaP significantly. In acidic or alkaline conditions, the photocatalytic degradation rates of the PAHs were greater than those in neutral conditions. Humic acid significantly enhanced the PAH photocatalytic degradation by sensitizing radicals capable of oxidizing PAHs.


2021 ◽  
Author(s):  
Zhao Wang ◽  
Xiangzi Jin ◽  
Han Yeong Kaw ◽  
Zakia Fatima ◽  
Maurizio Quinto ◽  
...  

Abstract Due to their wide distribution and availability, plant leaves can be considered interesting candidates as biomonitoring substrates for the evaluation of atmospheric pollution. In addition, some species can also retain historical information, for example, related to environmental pollution, due to their leaf class age. In this study, the content of polycyclic aromatic hydrocarbons (PAHs) in Abies holophylla and Pinus tabuliformis needle samples in function of their class age has been investigated to obtain information regarding the degradation constant for each PAH under investigation (α values ranging from 0.173 to 1.870) and to evaluate the possibility to correlate the presence of PAHs in needles with some important pollution environmental factors. Considering air pollutant variables registered in Jilin Province, significant correlations (at 95% confidence level) have been found between coal consumption per year and anthracene contents in needles, while fluorene, phenanthrene, and anthracene resulted correlated with coal consumption. Furthermore, it has been demonstrated that the total PAH concentration in needles, for both species, increased with their age (from 804 to 3604 ng g− 1 dry weight), showing a general tendency to accumulate these substances through years. PAH degradation rates increased instead with molecular complexity. This study could be considered a first trial to obtain historical environmental information by pine needles biomonitoring.


2015 ◽  
Vol 3 (2) ◽  
pp. 600-607 ◽  
Author(s):  
Hanxing Chen ◽  
Ming Wen ◽  
Zaidi Huang ◽  
Qingsheng Wu ◽  
Jiali Liu ◽  
...  

Novel Cu@ZnO core–shell nanobrushes exhibit high-performance photocatalytic selective degradation of polycyclic aromatic hydrocarbons (PAHs) under UV irradiation.


2021 ◽  
Author(s):  
Zhao Wang ◽  
Xiangzi Jin ◽  
Han Yeong Kaw ◽  
Zakia Fatima ◽  
Maurizio Quinto ◽  
...  

Abstract Due to their wide distribution and availability, plant leaves can be considered interesting candidates as biomonitoring substrates for the evaluation of atmospheric pollution. In addition, some species can also retain historical information, for example, related to environmental pollution, due to their leaf class age. In this study, the content of polycyclic aromatic hydrocarbons (PAHs) in Abies holophylla and Pinus tabuliformis needle samples in function of their class age has been investigated to obtain information regarding the degradation constant for each PAH under investigation (α values ranging from 0.173 to 1.870) and to evaluate the possibility to correlate the presence of PAHs in needles with some important pollution environmental factors. Considering air pollutant variables registered in Jilin Province, significant correlations (at 95% confidence level) have been found between coal consumption per year and anthracene contents in needles, while fluorene, phenanthrene, and anthracene resulted correlated with coal consumption. Furthermore, it has been demonstrated that the total PAH concentration in needles, for both species, increased with their age (from 804 to 3604 ng g− 1 dry weight), showing a general tendency to accumulate these substances through years. PAH degradation rates increased instead with molecular complexity. This study could be considered a first trial to obtain historical environmental information by pine needles biomonitoring.


2018 ◽  
Vol 83 (5) ◽  
pp. 549-559 ◽  
Author(s):  
Xin Wang ◽  
Yu Shi ◽  
Zi Ni ◽  
Zhao Li ◽  
Jia Bao

The biodegradation of polycyclic aromatic hydrocarbons (PAHs) in soils by laccase is reported. However, the low laccase activities of free laccase have limited its applications in environmental bioremediation. In this study, polluted soil was made with 3:1 volume ratio of soil to PAH solution. Subsequently, the adsorption?cross-link composite immobilization method was applied to immobilize laccase derived from fungi onto nylon net and chitosan, respectively. These two kinds of immobilized laccase were used in the degradation of pyrene (Pyr) and benzo[a]pyrene (BaP), and their degradation efficiencies under different temperature and pH conditions were investigated. Consequently, the optimal laboratory experimental parameters were determined as follows: first, compared with free laccase, the degradation rates of Pyr and BaP by immobilized laccase increased by around 10?30 %; second, the degradation efficiency of chitosan as a carrier of immobilized laccase was much better than that of nylon net as a carrier of the immobilized laccase; finally, when the temperature was set at 40?C and the pH was set at 4, the degradation efficiency achieved by immobilized laccase was the best.


Author(s):  
Rekha Nagwanshi ◽  
Dr. Jeeven Singh Solanki ◽  
Sandhya Bageriab ◽  
Shubha Jain

Polycyclic aromatic hydrocarbons (PAHs) are a class of genotoxic environmentalcontaminants and are always exposed to solar radiations. Fluorenes are important PAHswidely distributed in nature and hence the studies in the effect of light on them are of ulmostsignificance. Therefore in this paper, we have studied the photo irradiations of fluorene (1)and 9-fluorenone (2) with UV light in different solvents, which results in the formation ofdifferent products.


2021 ◽  
Author(s):  
Andrew D. McQueen ◽  
Mark L. Ballentine ◽  
Lauren R. May ◽  
Charles H. Laber ◽  
Arit Das ◽  
...  

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