Photocatalytic degradation of dyes in aqueous solution operating in a fluidised bed reactor.
This work reports a preliminary design of a new photochemical reactor and its application to photochemical degradation of two dyes, Crystal Violet and Azure B, operating in both batch and continuous processes. A novel kind of photocatalyst, consisting of ZnO immobilised in alginate gel beads, which is able to photodegrade organic dyes effectively, has been employed in the present study. When this photocatalyst, at a concentration of 1 g of ZnO per litre of alginate gel at 3%, was employed in batch process, almost total decolourisation of Crystal Violet in reaction times lower than 120 min was observed. Operating in continuous process at different residence times, it was possible to achieve a total decolourisation of both Crystal Violet and Azure B. Moreover, the total organic carbon content (TOC) was reduced to 90% in the former and to 52% in the latter. These results indicated that the photoreactor developed in the present work was able to degrade effectively dyes of different structures, revealing the non-specificity of the system.
Couto
S Rodríguez
SR
Department of Chemical Engineering. University of Vigo, Spain. sanroman@uvigo.es
Domínguez
A
A
Sanromán
A
A
D000464:Alginates; D001399:Azure Stains / Q000737:chemistry / Q000302:isolation & purification / Q000528:radiation effects; D019149:Bioreactors; D002244:Carbon / Q000378:metabolism; D004396:Coloring Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000528:radiation effects; D005840:Gentian Violet / Q000737:chemistry / Q000302:isolation & purification / Q000528:radiation effects; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D007220:Industrial Waste / Q000032:analysis*; D007700:Kinetics; D010782:Photolysis / Q000187:drug effects / Q000528:radiation effects*; D013053:Spectrophotometry; D014865:Waste Disposal, Fluid / Q000379:methods*; D014867:Water / Q000737:chemistry; D015034:Zinc Oxide / Q000008:administration & dosage
D000464:Alginates; D001399:Azure Stains; D004396:Coloring Agents; D006603:Hexuronic Acids; D007220:Industrial Waste; D014867:Water; D002244:Carbon; C025819:Azure B; D020723:Glucuronic Acid; D005840:Gentian Violet; D015034:Zinc Oxide