Document Detail


Visible light Cr(VI) reduction and organic chemical oxidation by TiO2 photocatalysis.
MedLine Citation:
PMID:  16173589     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Here we report the simultaneous Cr(VI) reduction and 4-chlorophenol (4-CP) oxidation in water under visible light (wavelength > 400 nm) using commercial Degussa P25 TiO2. This remarkable observation was attributed to a synergistic effect among TiO2, Cr(VI), and 4-CP. It is well known that TiO2 alone cannot remove either 4-CP or Cr(VI) efficiently under visible light. Moreover, the interaction between Cr(VI) and 4-CP is minimal if not negligible. However, we found that the combination of TiO2, Cr(VI), and 4-CP together can enable efficient Cr(VI) reduction and 4-CP oxidation under visible light. The specific roles of the three ingredients in the synergistic system were studied parametrically. It was found that optimal concentrations of Cr(VI) and TiO2 exist for the Cr(VI) reduction and 4-CP oxidation. Cr(VI) was compared experimentally with other metals such as Cu(ll), Fe(lll), Mn(IV), Ce(IV), and V(V). Among all these metal ions, only Cr(VI) promotes the photocatalytic oxidation of 4-CP. The amount of 4-CP removed was directly related to the initial concentration of Cr(VI). The system was also tested with four other chemicals (aniline, salicylic acid, formic acid, and diethyl phosphoramidate). We found that the same phenomenon occurred for organics containing acid and/or phenolic groups. Cr(VI) was reduced at the same time as the organic chemicals being oxidized during photoreaction under visible light. The synergistic effect was also found with pure anatase TiO2 and rutile TiO2. This study demonstrates a possible economical way for environmental cleanup under visible light.
Authors:
Bo Sun; Ettireddy P Reddy; Panagiotis G Smirniotis
Related Documents :
24276709 - Isolation of biochemical mutants using haploid mesophyll protoplasts of hyoscyamus muti...
23679209 - Rhodium-catalyzed decarbonylative c-h arylation of 2-aryloxybenzoic acids leading to di...
24284429 - Pathways of lipid metabolism in marine algae, co-expression network, bottlenecks and ca...
25007409 - Stereospecific microbial conversion of lactic acid into 1,2-propanediol.
24808759 - Modern applications for a total sulfur reduction distillation method - what's old is ne...
24839309 - Poly(carbonate-amide)s derived from bio-based resources: poly(ferulic acid-co-tyrosine).
7204679 - Analysis of hair from alopecia congenita.
9016769 - Purification of the human rargamma ligand-binding domain and crystallization of its com...
3919969 - Intramucosal activation of pepsinogens in the pathogenesis of acute gastric erosions an...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Environmental science & technology     Volume:  39     ISSN:  0013-936X     ISO Abbreviation:  Environ. Sci. Technol.     Publication Date:  2005 Aug 
Date Detail:
Created Date:  2005-09-21     Completed Date:  2005-12-14     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0213155     Medline TA:  Environ Sci Technol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  6251-9     Citation Subset:  IM    
Affiliation:
Chemical and Material Engineering Department, University of Cincinnati, Cincinnati, Ohio 45221-0012, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Carcinogens, Environmental / chemistry*,  isolation & purification
Catalysis
Chlorophenols / chemistry
Chromium / chemistry*,  isolation & purification
Coloring Agents / chemistry
Environmental Pollution / prevention & control
Oxidation-Reduction
Photochemistry
Titanium / chemistry
Water / chemistry
Chemical
Reg. No./Substance:
0/Carcinogens, Environmental; 0/Chlorophenols; 0/Coloring Agents; 106-48-9/4-chlorophenol; 13463-67-7/titanium dioxide; 18540-29-9/chromium hexavalent ion; 7440-32-6/Titanium; 7440-47-3/Chromium; 7732-18-5/Water

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Bisphenol A removal from water by activated carbon. Effects of carbon characteristics and solution c...
Next Document:  Reducing the emission of particles from a diesel engine by adding an oxygenate to the fuel.