Removal of CI Acid Blue 29 from an aqueous solution by Aspergillus niger

Removal of C.I. Acid Blue 29 from an aqueous solution by biosorption on dea d Aspergillus niger fungus was investigated. Pretreatment with sulfuric aci d was most effective with a biosorption capacity of 13.82 mg/g biomass comp ared with 6.63 mg/g of living biomass. Batch pH, kinetic, and isotherm stud ies were conducted to evaluate the biosorption capacity of the most effecti ve pretreated biomass. The pH of the dye solution strongly affected the bio sorption capacity. The effective pH was 4 and the corresponding biosorption capacity was 18.15 mg/g biomass. The kinetic studies showed that equilibri um was reached in 24 hours, and Lagergren first-order and Ho, et al. pseudo second-order rate equations were able to provide a realistic description o f biosorption kinetics. Isotherm studies indicated that biosorption followe d the Langmuir, Freundlich, and BET isotherms models.