Photocatalytic ozonation of phenolic wastewaters: Syringic acid, tyrosol and gallic acid.
The photocatalytic ozonation of a mixture of 3 phenols (gallic acid, tyrosol and syringic acid) has been conducted under different operating conditions. The individual adsorption of the phenol type compounds onto titanium dioxide (photocatalyst) has been first evaluated. Equilibrium conditions are attained in less than an hour while the isotherm curves reveal that adsorption intensity increases in order: syringic acid < tyrosol < gallic acid. When the photocatalytic ozonation is applied, an optimum in titanium dioxide concentration is experienced (1.5 g L(-1)). Direct comparison of the photocatalytic ozonation to other less sophisticated oxidation systems (i.e., single ozonation, catalytic ozonation, photo-ozonation, etc.) indicates a higher efficiency of the former in terms of ozone uptake.
Gimeno
Olga
O
Departamento de Ingeniería Química y Química Física, Edificio Jose Luis Sotelo, Facultad de Ciencias, Badajoz, Spain. ogimeno@unex.es
Fernandez
Lidia A
LA
Carbajo
Maria
M
Beltran
Fernando
F
Rivas
Javier
J
D000327:Adsorption; D002384:Catalysis; D010083:Oxidants, Photochemical / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry / Q000528:radiation effects; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000528:radiation effects; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000528:radiation effects; D018508:Water Purification / Q000379:methods
D010083:Oxidants, Photochemical; D010636:Phenols; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; C011867:4-hydroxyphenylethanol; D010126:Ozone; D014025:Titanium; D010626:Phenylethyl Alcohol