Triarylmethane Dye Decolorization by Pellets of Pycnoporus sanguineus: Statistical Optimization and Effects of Novel Impeller Geometry

ABSTRACT

A study was carried out to optimize selected parameters for decolorization of a triarylmethane dye, such as crystal violet by white rot fungus, Pycnoporus sanguineus, pellets. The parameters studied were initial dye concentration (ppm), agitation speed (rpm), and process time (days) and were optimized using response surface methodology (RSM). It is shown that process time, agitation speed, and their interactions have significant effects on the decolorization process. Following the optimization, the decolorization study was extended to a stirred tank reactor (STR) process. Effects of different geometry of impellers on the decolorization process and power consumption were studied. Novel impeller geometries, such as 180° curved blade and 60° angled blade impellers, were used in the STR. The application of 180° curved blade impeller resulted in higher percentage of decolorization at a relatively less power consumption as compared with 60° angled blade impeller.

KEYWORDS:

• crystal violet
• decolorization
• impeller geometry
• power consumption
• Pycnoporus sanguineus
• response surface methodology

ACKNOWLEDGMENTS

The authors acknowledge University of Malaya for research grants RP024-2012A and UM.C/625/1/HIR/ MOHE/05, and they thank Dr. S. Vikineswary from Institute of Biological Sciences, University of Malaya, for providing the fungal strain.