DIKUL - logo
ALL libraries (COBIB.SI union bibliographic/catalogue database)
  • Thermolysis of 2,4,6-trichlorophenol chemisorbed on aluminium oxides as example of fly ash mediated surface catalysis reaction in PCDD/PCDF formation
    Vončina, Ernest ; Šolmajer, Tomaž
    The influence of aluminium cation as a strong electrophilic centre on the thermolysis of chlorophenols chemisorbed on Al(OH)3 surface was investigated. If thermolysis is carried out at 300°C the ... spontaneous rupture of the bond between aluminium and oxygen of phenol takes place in the temperature range of 260 - 280°C. The thermolysis of chlorophenoxy aluminium compounds occurs through homolytic and heterolytic bond cleavage. In the case of heterolytic cleavage the leaving chlorophenoxy anion causes a simultaneous formation of the aluminium cation, which is the driving force for the rearrangement of the unstable intermediate. By homolytic cleavage of the Al-O bond the chlorophenoxy radical is formed. The isolation of reaction products of the thermolysis of the system Al(OH)3/2,4,6-trichlorophenol gave five isomers of dimeric compounds of resonance stabilised 2,4,6-trichlorophenoxy radical. The compounds are stable in nonaqueous,aprotic solution, but they are very sensitive to acid catalysis. They quickly transform into aromatic hydroxydiphenyl ethers. The process of dechlorination and aromatisation of cyclohexadienone dimers gives PCDD/PCDF.
    Source: Chemosphere. - ISSN 0045-6535 (Vol. 46, 2002, str. 1279-1286)
    Type of material - article, component part
    Publish date - 2002
    Language - english
    COBISS.SI-ID - 7018774

source: Chemosphere. - ISSN 0045-6535 (Vol. 46, 2002, str. 1279-1286)
loading ...
loading ...
loading ...