Coupling of chemical, electrochemical and ultrasonic energies for controlled generation of hydroxyl radicals - Direct synthesis of phenol by benzene hydroxylation

被引:37
作者
Bremner, DH [1 ]
Burgess, AE [1 ]
Li, FB [1 ]
机构
[1] Univ Abertay Dundee, Sch Sci & Engn, Div Mol & Life Sci, Dundee DD1 1HG, Scotland
基金
英国工程与自然科学研究理事会;
关键词
hydroxyl radicals; Fenton catalytic conditions; electrochemistry; ultrasound; phenol synthesis; iron catalysis; coupled energies;
D O I
10.1016/S0926-860X(00)00479-8
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
Hydroxyl radicals HO. are generated under Fenton-like (Fe2++H2O2-->HO.+OH-+Fe3+) catalytic conditions using chemical, electrochemical and ultrasonic energies in combination. The resulting hydroxyl radicals are utilised in a model reaction in which benzene is hydroxylated directly to produce phenol. Chemical energy alone using a FeCl2 catalyst supported on silica gel gives synthetic yields of ca. 2% (calculated on benzene initially present), which are increased to 13-15% when irradiated with ultrasound. Coupled chemical and electrochemical synthesis in which the Fe2+ catalyst is generated in situ through controlled dissolution of an iron electrode produces yields of 10-13%. Higher yields (15-20%) are obtained when ultrasonic energy is coupled with the chemical-electrochemical method. The merits and limitations of these different methods and the significance of the yields of the model reaction in terms of the efficiency of radical generation are discussed. it is concluded that the combined chemical-electrochemical-ultrasonic approach offers more effective control of energy input for hydroxyl radical generation appropriate to various synthetic reactions. The direct synthesis of phenol approaches a limiting yield of ca. 20% when competing side reactions, such as further oxidation, occur. (C) 2000 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:111 / 120
页数:10
相关论文
共 28 条
  • [1] [Anonymous], 1990, ADV SONOCHEMISTRY
  • [2] Investigation into the effect of ultrasound on the dimerization of pivalic acid using Fenton's reagent
    Bremner, DH
    Mitchell, SR
    Staines, H
    [J]. ULTRASONICS SONOCHEMISTRY, 1996, 3 (01) : 47 - 52
  • [3] ELECTROCHEMICAL DESTRUCTION OF ANILINE AND 4-CHLOROANILINE FOR WASTE-WATER TREATMENT USING A CARBON-PTFE O-2-FED CATHODE
    BRILLAS, E
    BASTIDA, RM
    LLOSA, E
    CASADO, J
    [J]. JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1995, 142 (06) : 1733 - 1741
  • [4] Degradation of 4-chlorophenol by anodic oxidation, electro-Fenton, photoelectro-Fenton, and peroxi-coagulation processes
    Brillas, E
    Sauleda, R
    Casado, J
    [J]. JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1998, 145 (03) : 759 - 765
  • [5] Iron(II) catalysis of the mineralization of aniline using a carbon-PTFE O-2-fed cathode
    Brillas, E
    Mur, E
    Casado, J
    [J]. JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1996, 143 (03) : L49 - L53
  • [6] SYNTHESES BY FREE-RADICAL REACTIONS .1. OXIDATIVE COUPLING EFFECTED BY HYDROXYL RADICALS
    COFFMAN, DD
    JENNER, EL
    LIPSCOMB, RD
    [J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1958, 80 (11) : 2864 - 2872
  • [7] Sonoelectrochemical production of hydrogen peroxide at polished boron-doped diamond electrodes
    Compton, RG
    Marken, F
    Goeting, CH
    McKeown, RAJ
    Foord, JS
    Scarsbrook, G
    Sussmann, RS
    Whitehead, AJ
    [J]. CHEMICAL COMMUNICATIONS, 1998, (18) : 1961 - 1962
  • [8] ELECTROCATALYSIS OF ANODIC OXYGEN-TRANSFER REACTIONS - THE ELECTROCHEMICAL INCINERATION OF BENZOQUINONE
    FENG, JR
    HOUK, LL
    JOHNSON, DC
    LOWERY, SN
    CAREY, JJ
    [J]. JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1995, 142 (11) : 3626 - 3632
  • [9] Heitz E., 1974, ADV CORROS SCI TECH, V4, P149, DOI [10.1007/978-1-4615-9059-0_3, DOI 10.1007/978-1-4615-9059-0_3]
  • [10] KEDDAM M, 1995, CORROSION MECH THEOR, P55