Application of taguchi L16 orthogonal array design to optimize hydrazine biosorption by Sargassum ilicifolium

In this work, Taguchi L-16 experimental design was applied to optimize biosorption of hydrazine by Sargassum ilicifolium in a batch system. Biosorption tests were performed with four factors concentration, pH, biosorbent dosage, and agitation time at four different levels. Optimal experimental conditions were determined by calculated signal-to-noise ratios. The best conditions for biosorption of hydrazine were determined by the Taguchi method and desirability approach as initial hydrazine concentration of 135 mg/L, pH=7.5, biosorbent dose of 0.1 g/L and time 90 min. Furthermore, thermodynamic, isotherm and kinetic studies were performed to explain the biosorption mechanism. The kinetic of hydrazine removal followed the pseudo-second-order model. A nonlinear regression was applied to fit the experimental data with several isotherm models. The Redlich-Peterson and Radke-Prausnitz isotherms showed the best concordance as equilibrium models. Nature of possible interactions between the functional groups of S. ilicifolium and hydrazine was confirmed by FTIR spectra of raw and hydrazin-loaded alga. (c) 2016 American Institute of Chemical Engineers Environ Prog, 35: 1450-1457, 2016