Journal of the Faculty of Engineering and Architecture of Gazi University, vol.38, no.4, pp.1979-1993, 2023 (SCI-Expanded)
Conventional and sonication-assisted biosorption of Remazol Orange RGB dye by active kefir biomass was investigated. SEM, FTIR and BET analyses were used to characterise the biomass. Experiments were carried out in batch mode and the effects of pH, initial dye concentration and temperature on dye removal were examined. Biosorption of dye increased with the rise in temperature and the reduce in initial pH and initial concentration of dye in both processes. At all examined conditions due to the assistance of sonication higher biosorption yields were obtained. 74.62% and 95.18% dye removals were achieved at pH 2, initial dye concentration of 100 mg L-1 and 25℃ for conventional and sonication assisted biosorption that the equilibrium was attained respectively in 210 and 45 minutes. It was determined that the conventional biosorption process could be expressed with the pseudo first order kinetic model and the sonication assisted biosorption process could be expressed with the pseudo second order kinetic model, while the biosorption equilibrium for both processes could be expressed with the Langmuir isotherm model. The isotherm model showed that the maximum biosorption capacity values of kefir biomass in conventional and sonication assisted biosorption were 90.33 mg/g and 107.99 mg/g, respectively. Thermodynamic analysis confirmed that the biosorption processes are spontaneous, endothermic and physical in nature. The results demonstrated that sonication is an effective and useful method to improve the biosorption processes with living organisms.