tailieunhanh - Báo cáo hóa học: " Photocatalytic Degradation of Two Commercial Reactive Dyes in Aqueous Phase Using Nanophotocatalysts"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Photocatalytic Degradation of Two Commercial Reactive Dyes in Aqueous Phase Using Nanophotocatalysts | Nanoscale Res Lett 2009 4 709-716 DOI s11671-009-9300-3 NANO EXPRESS Photocatalytic Degradation of Two Commercial Reactive Dyes in Aqueous Phase Using Nanophotocatalysts Sushil Kumar Kansal Navjeet Kaur Sukhmehar Singh Received 12 November 2008 Accepted 24 March 2009 Published online 10 April 2009 to the authors 2009 Abstract This study involves the photocatalytic degradation of Reactive Black 5 RB5 and Reactive Orange 4 RO4 dyes employing heterogeneous photocatalytic process. Photocatalytic activity of different semiconductors such as titanium dioxide TiO2 and zinc oxide ZnO has been investigated. An attempt has been made to study the effect of process parameters through amount of catalyst concentration of dye and pH on photocatalytic degradation of RB5 and RO4. The experiments were carried out by varying pH 3-11 amount of catalyst g L and initial concentration of dye 10-100 mg L . The optimum catalyst dose was found to be and 1 g L for RB5 and RO4 respectively. In the case of RB5 maximum rate of decolorization was observed in acidic medium at pH 4 whereas the decolorization of RO4 reached maximum in basic region at pH 11. The performance of photocatalytic system employing ZnO UV light was observed to be better than TiO2 UV system. The complete decolorization of RB5 was observed after 7 min with ZnO whereas with TiO2 only 75 dye degraded in 7 min. In the case of RO4 92 and 62 decolorization was noticed in the same duration. Keywords Decolorization Azo dye Reactive Black 5 Reactive Orange 4 Photocatalysis Zinc oxide Nanophotocatalyst S. K. Kansal El N. Kaur S. Singh Department of Chemical Engineering Technology Panjab University Chandigarh 160014 India e-mail sushilkk1@ Introduction Textile industries produce large volume of colored dye effluents which are toxic and non-biodegradable 1 . Among the different types of dyes used in textile industries 60-70 are azo compounds. These dyes create severe environmental pollution problems by