Solar photocatalytic degradation of phenol by TiO2/AC prepared by temperature impregnation method

摘要

Solar photocatalytic degradation of phenol by TiO2 (p25), which was immobilized on powdered activated carbon (TiO2/AC) by temperature impregnation method, was investigated. Solar compound parabolic collectors reactor with a capacity of 4.0L was used. Characterization of TiO2/AC by Brunauer-Emmett-Teller analysis, Fourier transform infrared spectroscopy, and scanning electron microscope revealed successful impregnation of TiO2 particles on activated carbon (AC). Fifty three percent degradation of phenol was recorded at irradiation time of 30min and increased up to 80% after 150min using TiO2. This was not the case for TiO2/AC, where the phenol was rapidly removed by a value of 40% within 15min and complete degradation of phenol was attained at illumination time of 120min. This indicates that immobilization of TiO2 on AC is very effective for phenol degradation. Moreover, in TiO2/AC photocatalysis, the presence of aromatic intermediates (catechol, hydroquinone, and p-benzoquinone) was relatively lower as compared to TiO2 photocatalysis. However, TiO2/AC photocatalysis of phenol degradation is strongly affected by pH values and dosage of the catalyst, i.e. complete degradation of phenol was occurred at pH value of 5.3 and dosage of 1.2g/L. The photocatalytic degradation of phenol by TiO2/AC followed the pseudo-first-order kinetic according to Langmuir-Hinshelwood model. Costs estimation of full-scale solar oxidation plant with life time of 20years was assessed. The results showed that complete removal of phenol using TiO2/AC costs 3.19 (sic)/m(3).