PMID- 16262326
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20070504
LR  - 20051102
IS  - 0743-7463 (Print)
IS  - 0743-7463 (Linking)
VI  - 21
IP  - 23
DP  - 2005 Nov 8
TI  - Enhanced photodegradation of 2,4,6-trichlorophenol over palladium 
      phthalocyaninesulfonate modified organobentonite.
PG  - 10602-7
AB  - This article explores a supported photocatalyst of palladium(II) 
      phthalocyaninesulfonate (PdPcS) onto organoclay for removal of 
      2,4,6-trichlorophenol (TCP) from water under visible light (lambda > or = 450 nm) 
      irradiation. The composite clay was not only a good sorbent for uptake of TCP 
      from water, but it also exhibited notable activity for TCP oxidation via singlet 
      molecular oxygen, generated in situ from PdPcS photosensitization. Complete 
      dechlorination of TCP could be achieved after TCP was totally oxidized. The 
      initial rate of TCP degradation was observed to increase with the initial amount 
      of TCP sorption, the kinetics following well the Langmuir-Hinshelwood equation. 
      The resulting rate constant of TCP oxidation was found to increase with the alkyl 
      chain length of the intercalated surfactant from dodecyltrimethylammonium to 
      cetyltrimethylammonium and to octadecyltrimethylammonium. Such the trend in 
      photoactivity was in agreement with the catalyst capacity for TCP sorption from 
      aqueous medium. The result showed that enrichment of toxic TCP on the catalyst 
      was indeed an efficient way for enhancement of the photosensitized degradation of 
      target pollutant. However, PdPcS loading led to a notable decrease in TCP 
      sorption, because of partial blocking of the sorptive sites. The optimal loading 
      of PdPcS was about 1.0 wt %. The catalyst was characterized by nitrogen 
      adsorption, X-ray diffraction, visible diffuse reflectance spectroscopy, and TCP 
      sorption, which revealed that the incorporated PdPcS, mainly in the form of 
      photoactive monomer, coexisted with the intercalated surfactant in the bentonite 
      interlayers. Seven repeated experiments demonstrated that the composite clay was 
      relatively stable and could be repeatedly used for sorption and degradation of 
      TCP pollutant via molecular oxygen and visible light.
FAU - Xiong, Zhigang
AU  - Xiong Z
AD  - Department of Chemistry, Zhejiang University, Hangzhou, China.
FAU - Xu, Yiming
AU  - Xu Y
FAU - Zhu, Lizhong
AU  - Zhu L
FAU - Zhao, Jincai
AU  - Zhao J
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Langmuir
JT  - Langmuir : the ACS journal of surfaces and colloids
JID - 9882736
EDAT- 2005/11/03 09:00
MHDA- 2005/11/03 09:01
CRDT- 2005/11/03 09:00
PHST- 2005/11/03 09:00 [pubmed]
PHST- 2005/11/03 09:01 [medline]
PHST- 2005/11/03 09:00 [entrez]
AID - 10.1021/la051714w [doi]
PST - ppublish
SO  - Langmuir. 2005 Nov 8;21(23):10602-7. doi: 10.1021/la051714w.