Abstract
In this study, adsorption of catalase enzyme onto activated carbon obtained from apple shell, kinetic parameters, and activation data of adsorption process was investigated. Temperature (15, 25, 36.5, and 45 degrees C), solution pH (5.5, 7, and 9), initial catalase enzyme concentration (1.10(-1), 2.10(-1), and 2.5.10(-1) g l(-1)), and ionic strength (1.10(-2), 5.10(-2), and 7.5.10(-2) M) have taken as kinetic parameters for the adsorption of catalase enzyme on activated carbon. In all runs, common parameters of temperature, pH, initial enzyme concentration, and ionic strength were taken as 298 K, pH 7, 0.2 g l(-1), and 5.10(-2) M, respectively. The results of experiments revealed that the adsorption of catalase enzyme onto activated carbon increased with increasing temperature (15-45 degrees C), ionic strength, and initial catalase enzyme concentration. However, the adsorption process of catalase on activated carbon was affected negatively by increased pH. The thermodynamic functions such as enthalpy (Delta H), activation energy (E-a), entropy (Delta S), and Gibbs energy (Delta G) were investigated. Delta G, E-a, Delta H, and Delta S were found to be - 70.61, 4.19, - 1.69 kJ mol(-1), and 231 J mol(-1) K-1 for catalase enzyme adsorption, respectively. The adsorption of the process was investigated using Eyring and Arrhenius equations, and the findings showed that the adsorption kinetic is coherent with the pseudo-second-order model. Eventually, activated carbon can be used as an effective adsorbent for the adsorption of catalase.