EQUILIBRIUM AND THERMODYNAMICS OF AZO DYES BIOSORPTION ONTO Spirulina platensis

作者：Dotto G L; Vieira M L G; Esquerdo V M; Pinto L A A^*

来源：Brazilian Journal of Chemical Engineering, 2013, 30(1): 13-21.

DOI：10.1590/s0104-66322013000100003

• Biosorption
• Spirulina platensis
• Azo dyes

The equilibrium and thermodynamics of azo dye (tartrazine and allura red) biosorption onto Spirulina platensis biomass were investigated. The equilibrium curves were obtained at 298, 308, 318 and 328 K, and four isotherm models were fitted the experimental data. Biosorption thermodynamic parameters (Delta G, Delta H and Delta S) were estimated. The results showed that the biosorption was favored by a temperature decrease. For both dyes, the Sips model was the best to represent the equilibrium experimental data (R-2>0.99 and ARE<5.0%) and the maximum biosorption capacities were 363.2 and 468.7 mg g(-1) for tartrazine and allura red, respectively, obtained at 298 K. The negative values of Delta G and Delta H showed that the biosorption of both dyes was spontaneous, favorable and exothermic. The positive values of Delta S suggested that the system disorder increases during the biosorption process.

• 出版日期2013-3