Semiconductor-Mediated Photocatalysed Degradation of Various Pesticide Derivatives and Other Priority Organic Pollutants in Aqueous Suspensions

2005 ◽  
Vol 486-487 ◽  
pp. 61-64
Author(s):  
Detlef W. Bahnemann ◽  
M. Muneer ◽  
M. Qamar ◽  
M.A. Rahman ◽  
H.K. Singh
Keyword(s):  
Titanium Dioxide ◽  
Organic Carbon ◽  
Organic Pollutants ◽  
Spectroscopic Analysis ◽  
Vibrio Fischeri ◽  
Degradation Kinetics ◽  
Irradiation Time ◽  
Aqueous Suspensions ◽  
Degradation Rates ◽  
Hplc Technique

The photocatalysed degradation of various selected pesticide derivatives, namely N,NDimethyl- a-phenyl benzene acetamide (Diphenamid) [1], 1,2-diethyl phthalate (DEP) [2], 5-bromo- 3-sec.butyl-6-methyl uracil (Bromacil) [3], 3-tert-butyl-5-chloro-6-methyluracil (Terbacil), 2,4,5- tribromoimidazole (TBI) [4], Methoxychlor, Chlorothalonil and Disulfoton [5] as well as that of two selected priority organic pollutants, namely benzidine and 1,2-diphenyhydrazine (DPH) [6], has been investigated in aqueous suspensions of titanium dioxide (TiO2) under a variety of conditions. The degradation was studied by monitoring the change in substrate concentration employing UV spectroscopic analysis or HPLC technique and the decrease in total organic carbon (TOC) content, respectively, as a function of irradiation time. The degradation kinetics was studied under different conditions such as reaction pH, substrate and photocatalyst concentration, type of photocatalysts and the presence of alternative additives such as H2O2, KBrO3 and (NH4)2S2O8 besides molecular oxygen. The degradation rates and the photonic efficiencies were found to be strongly influenced by the above parameters. A toxicity test was performed for irradiated samples of few selected systems measuring the luminescence of bacteria Vibrio fischeri after 30 minutes of incubation.

Semiconductor Mediated Photocatalysed Reaction of Two Selected Organic Compounds in Aqueous Suspensions of Titanium Dioxide

2012 ◽  
Vol 15 (2) ◽  
Author(s):  
Niyaz A. Mir ◽  
M.M. Haque ◽  
A. Khan ◽  
K. Umar ◽  
M. Muneer ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Titanium Dioxide ◽  
Organic Carbon ◽  
Photocatalytic Degradation ◽  
Organic Compounds ◽  
Substrate Concentration ◽  
Degradation Kinetics ◽  
Irradiation Time ◽  
Aqueous Suspensions ◽  
Kinetics Of

AbstractSemiconductor mediated hydrogen peroxide-assisted photocatalytic degradation of two selected pesticide compounds, chloramben (1) and cyanazine (2) has been investigated in aqueous suspensions under a variety of conditions. The degradation was studied by monitoring the depletion in total organic carbon (TOC) content and decrease in substrate concentration as a function of irradiation time. The degradation kinetics of pesticide compounds 1 and 2 were investigated under different conditions such as type of TiO

Titanium Dioxide-mediated Photocatalysed Mineralization of Two Selected Organic Pollutants in Aqueous Suspensions

2013 ◽  
Vol 16 (2) ◽  
Author(s):  
Khalid Umar ◽  
M. M. Haque ◽  
Niyaz A. Mir ◽  
M. Muneer ◽  
I. H. Farooqi
Keyword(s):  
Titanium Dioxide ◽  
Organic Pollutants ◽  
Hplc Analysis ◽  
Irradiation Time ◽  
Atmospheric Oxygen ◽  
Model Compounds ◽  
Aqueous Suspensions ◽  
Analysis Technique ◽  
Mineralization Kinetics ◽  
Kinetics Of

AbstractTitanium dioxide-mediated photocatalytic mineralization of two selected organic pollutants such as Metalaxyl (ML) and Tinidazole (TN) has been investigated in aqueous suspensions in the presence of atmospheric oxygen under a variety of conditions. The mineralization was studied by monitoring the depletion in total organic carbon (TOC) content as a function of irradiation time. In addition HPLC analysis technique was also used to monitor the degradation of model compounds under investigations. The mineralization kinetics of both compounds were investigated under different conditions such as type of TiO

Semiconductor-mediated photocatalysed degradation of two selected pesticide derivatives, terbacil and 2,4,5-tribromoimidazole, in aqueous suspension

2001 ◽  
Vol 44 (5) ◽  
pp. 331-337 ◽  
Author(s):  
M. Muneer ◽  
D. Bahnemann
Keyword(s):  
Hplc Analysis ◽  
Model Compound ◽  
Vibrio Fischeri ◽  
Degradation Kinetics ◽  
Irradiation Time ◽  
Aqueous Suspension ◽  
Toxicity Tests ◽  
Tio2 Photocatalyst ◽  
Degradation Rates ◽  
Ph Stat

The photocatalysed degradation of two selected pesticide derivatives, namely 3-tert-butyl-5-chloro-6-methyluracil (terbacil) and 2,4,5-tribromoimidazole (TBI) has been investigated in aqueous suspensions of titanium dioxide (TiO2) under a variety of conditions employing a pH-stat technique. The degradation was studied by monitoring the change in substrate concentration of the model compound employing HPLC analysis, and the decrease in total organic carbon (TOC) content, respectively, as a function of irradiation time. The degradation kinetics were studied under different conditions such as reaction pH, substrate and photocatalyst concentration, type of TiO2 photocatalyst and the presence of alternative additives such as H2O2, KBrO3 and (NH4)2S2O8 besides molecular oxygen. The degradation rates and the photonic efficiencies were found to be strongly influenced by the above parameters. Toxicity tests for the irradiated samples of the pesticide derivatives measuring the luminescence of bacteria Vibrio fischeri after 30 minutes of incubation were also performed.

Assessment of the use of red mud as a catalyst for photodegradation of bisphenol A in wastewater treatment

2016 ◽  
Vol 74 (6) ◽  
pp. 1283-1295 ◽  
Author(s):  
Raquel Vieira Busto ◽  
Maraisa Gonçalves ◽  
Lúcia Helena Gomes Coelho
Keyword(s):  
Wastewater Treatment ◽  
Bisphenol A ◽  
Red Mud ◽  
Vibrio Fischeri ◽  
Degradation Kinetics ◽  
Chemical Reduction ◽  
Aluminum Production ◽  
Synthetic Sample ◽  
Effluent Sample ◽  
Degradation Rates

This study aimed to investigate the use of red mud (RM) – a byproduct of aluminum production, as a photocatalyst, which was characterized physical-chemically and used in the photodegradation of the target compound bisphenol A (BPA). Chemical processing was performed in the RM (acid treatment, chemical reduction and calcination) to verify the most active catalyst. From the results obtained, a complete degradation kinetics of BPA was carried out using a synthetic matrix (BPA in deionized water) and a real matrix (BPA in wastewater) using natural RM/calcined and TiO2 for comparison. The results indicated the potential use of the RM/calcined, which was able to degrade between 88 and 100% of the pollutant in a synthetic sample. Tests on a real effluent sample resulted in degradation rates that ranged from 59 to 100% with chemical oxygen demand reductions of up to 23% using natural RM/calcined in comparison to TiO2. The blank system (irradiation of the solution without the use of a photocatalyst) and the natural RM/calcined one, resulted in reductions of the toxicity in the effluent sample (measured by EC20 using the marine bacteria Vibrio fischeri) of about 12 times, whereas the same treatment using TiO2 resulted in a toxicity reduction of only seven times. Within these results, the RM/calcined showed potential to be used in wastewater treatment in polishing processes.

Immobilization of Nano-TiO2 on Expanded Perlite for Photocatalytic Degradation of Rhodamine B

2011 ◽  
Vol 110-116 ◽  
pp. 3795-3800 ◽  
Author(s):  
Xiao Zhi Wang ◽  
Wei Wei Yong ◽  
Wei Qin Yin ◽  
Ke Feng ◽  
Rong Guo
Keyword(s):  
Catalytic Activity ◽  
Photocatalytic Degradation ◽  
Rhodamine B ◽  
Degradation Kinetics ◽  
Irradiation Time ◽  
Sol Gel ◽  
Polluted Water ◽  
Order Kinetic ◽  
Expanded Perlite ◽  
Initial Concentration

Expanded perlite (EP) modified titanium dioxide (TiO2) with different loading times were prepared by Sol-Gel method. Photocatalytic degradation kinetics of Rhodamine B (RhB) in polluted water by the materials (EP-nanoTiO2), as well as the effects of different loading times and the initial concentration of RhB on photocatalysis rate were examined. The catalytic activity of the regenerated photocatalyst was also tested. The results showed that photocatalyst modified three times with TiO2had the highest catalytic activity. Degradation ratio of RhB by EP-nanoTiO2(modified three times) under irradiation for 6 h were 98.0%, 75.6% and 63.2% for 10 mg/L, 20 mg/L and 30 mg/L, respectively.The photocatalyst activity has little change after the five times recycling, and the degradation rate of RhB decreased less than 8%. The reaction of photocatalysis for RhB with irradiation time can be expressed as first-order kinetic mode within the initial concentration range of RhB between 10mg/L and 30 mg/L. EP-nanoTiO2photocatalyst has a higher activity and stability to degrade RhB in aqueous solution.

Iron(III) Phthalocyanine-Modified Titanium Dioxide:  A Novel Photocatalyst for the Enhanced Photodegradation of Organic Pollutants

1998 ◽  
Vol 102 (47) ◽  
pp. 9397-9403 ◽  
Author(s):  
Koodali T. Ranjit ◽  
Itamar Willner ◽  
Stefan Bossmann ◽  
André Braun
Keyword(s):  
Titanium Dioxide ◽  
Organic Pollutants

Chemical characteristics and in situ ruminal parameters of barley for cattle: Comparison of the malting cultivar AC Metcalfe and five feed cultivars

2008 ◽  
Vol 88 (4) ◽  
pp. 711-719 ◽  
Author(s):  
Kenton J Hart ◽  
Brian G Rossnagel ◽  
Peiqiang Yu
Keyword(s):  
Nutritive Value ◽  
Degradation Kinetics ◽  
Starch Degradation ◽  
Barley Cultivars ◽  
Degradation Rates ◽  
Key Words Barley ◽  
In Situ Degradation ◽  
The Mean ◽  
Pass Through

The objective of this study was to compare the most widely grown barley cultivar in Canada, AC Metcalfe, a malting type barley, with five feed cultivars. Barley cultivars were grown at one location during 3 consecutive years and barley samples were milled to pass through a 1-mm screen and analysed to determine nutritive value. Additional samples were passed through a roller mill with a gap set at 1.12 mm and incubated ruminally for 0, 2, 4, 8, 12, 24, and 48 h in 3 dry Holstein cows fitted with rumen cannulae. The rate and extent of rumen digestion were estimated. AC Metcalfe had a higher (P < 0.001) concentration of NDF, and lower (P < 0.05) concentrations of non structural carbohydrates, starch, ADF, total digestible nutrients, and fermentable cell wall carbohydrates compared with the mean of the feed cultivars. The malting cultivar had a higher (P < 0.001) soluble DM fraction, lower (P < 0.05) CP and starch degradation rates, and a lower (P < 0.001) ruminally degradable starch concentration compared with the mean of the five feed cultivars. The results demonstrate that there are only small differences in terms of chemical composition and in situ degradation kinetics between the malting cultivar AC Metcalfe and the five feed cultivars of barley reported here. Key words: Barley, energy, protein, ruminants

Sign in / Sign up

Export Citation Format

Share Document