Removal of Reactive Blue 19 from Wastewaters by Physicochemical and Biological Processes-A Review

Abstract

The developments for the removal of reactive blue 19 dye (RB 19) by various physicochemical methods such as sonolysis, photocatalysis, electrochemical, ozonolysis, adsorption, hydrolysis and biological methods like microbial degradation, biosorption, chemical and biological reductive decolorization has been presented. It was found that none of the individual physical and chemical technique can be used in wastewater treatment with good economics and high energy efficiency. For example, the application of adsorption method is restricted as adsorbent materials requires frequent regenerations; ozonolysis and photocatalysis processes can efficiently decolorize and degrade the dye but these face operational difficulties are not cost effective. Similarly the performance of biological treatment processes is required to enhance by developing efficient strains of bacteria, fungi. The comparison of physiochemical and biological treatment of RB 19 dye suggested that biological treatment of RB 19 dye is comparatively cost-effective process. However, the integrated approach can be used to decolorize and degrade the dye by combining both physicochemical and biological processes.