Separation of Ni (II) from industrial wastewater by Kombucha Scoby as a colony consisted from bacteria and yeast: Kinetic and equilibrium studies

Abstract

Kombucha Scoby is a colony consisted from bacteria, yeast and cellulosic pellicle which has unique outcomes and performances in variety of fields. Along with antimicrobial and anti-toxicity of kombucha, it can be adapted to develop reactors for removal of heavy metals from waste water. The main objective of this study is to investigate the removal of Ni (II) ions from wastewater by Kombucha as a microorganism by considering the pH, time, temperature, the electrolyte solution, the buffer volume and type. The adsorption experiments indicated that the maximum adsorption capacity of Ni (II) occurred at the pH of 7, contact time of 15 min and temperature of 25 °C. In the optimal conditions, 94.5% of Ni (II) ions was removed from the solution, which clarify the significant effectiveness of Kombucha Scoby in matter of heavy metal removal. Besides, equilibrium experiments fitted well with the Langmuir isotherm model and the maximum Kombucha Scoby adsorption capacity at 25 °C was determined to be a very high adsorption capacity of 454.54 mg/g. Additionall, adsorption kinetic behaviour of Ni (II) on to the Kombucha Scoby can be described using the pseudo-second order model.