Study of the fast kinetic decolourisation of textile dyes by ozone using Quench-Flow method (CAT#: STEM-AC-0040-WXH)

Introduction

The environmental concern resulting from the increasing contamination of natural water supplies by refractory pollutants makes the use of less conventional depuration technologies highly pertinent, as it is the case of chemical oxidation. Thus, the powerful oxidizing capabilities of ozone alone or in combination with UV radiation and hydrogen peroxide are being increasingly applied to the treatment of wastewater effluents containing hazardous organic and inorganic compounds, namely pharmaceuticals, pesticides, aromatic compounds, absorbable organic halogens, textile dyes and many other chemicals, which are difficult or expensive to remove through biodegradation or through other physicochemical processes. Ozonation can be applied to achieve pollutants complete oxidation (i.e. mineralization) or for biodegradability enhancement through chemical breakdown of refractory compounds into smaller and less recalcitrant molecules by partial oxidation.<br />Under acidic conditions, ozone can directly react with organic substrates as an electrophile. Ozone is frequently used for decolorizing dye wastewaters because it attacks conjugated double bonds which are often associated with color.