The use of the white-rot fungus Polyporous versicolor in Ni(II) removal as biosorbent was investigated. Kinetic and isotherm sorption experiments were conducted to evaluate the effects of pH, time, temperature. and mixing intensity. Time-course variation of Ni(II) uptake at various temperatures (20, 25, and 35 degreesC) and initial Ni(II) concentrations revealed that both the initial Ni(II) uptake rate and the Ni(II) sorption capacity increased with increasing temperature. Ni(II) biosorption isotherms determined based on the Freundlich and Langmuir models adequately described the biosorption of Ni(II). As temperature increases, the Ni(II) adsorptive capacity of P. versicolor showed an increase that was much more pronounced when the temperature was increased from 20 to 25 degreesC. An increase in the initial concentration caused the metal uptake to increase more at 25 and 35 degreesC than at 20 degreesC. The temperature 35 degreesC appeared to be optimal and a maximum adsorption capacity of 57 mg/g was attained. ( C) 2002 Elsevier Science Ltd. All rights reserved.