Acta Phys. -Chim. Sin. ›› 2016, Vol. 32 ›› Issue (3): 638-646.doi: 10.3866/PKU.WHXB201512181

• ARTICLE • Previous Articles     Next Articles

Kinetics and Thermodynamics of Lysozyme Adsorption on Mesoporous Titanium Dioxide

Qi-Liang HONG1,Yi-Hui DONG1,Wei ZHUANG2,Chao RAO1,Chang LIU1,*()   

  1. 1 State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Technology University, Nanjing 210009, P. R. China
    2 School of Biological and Pharmaceutical Engineering, Nanjing Technology University, Nanjing 211816, P. R. China
  • Received:2015-09-14 Published:2016-03-04
  • Contact: Chang LIU
  • Supported by:
    the National Key Basic Research Program of China(2013CB733501);National Natural Science Foundation of China(21136004, 21476106, 21506090);Natural Science Foundation of Jiangsu Province, China(BK20130929);Project of Priority Academic Program Development (PAPD) of Jiangsu Higher Education Institutions, China


Mesoporous TiO2 was prepared by calcinating H2Ti205 at 773.15 K. The sample was characterized by Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), Raman spectroscopy, and X-ray diffraction (XRD) analysis. The adsorption behavior and mechanism of mesoporous TiO2 for lysozyme were investigated by isothermal adsorption experiments. The results show that the equilibrium experimental data were correlated with the Langmuir isotherm equation. The adsorption capacity first increased and then decreased with increasing pH value. The capacity showed a maximum value of 72.5 mg·g-1 when the pH value was 7.2. Lysozyme adsorbed on mesoporous TiO2 was extremely stable, and its amount on mesoporous TiO2 maintained 81.6% of its initial value after five adsorption and regeneration cycles. Furthermore, kinetic analysis was conducted using pseudo-first and pseudo-second order models. The adsorption of lysozyme on mesoporous TiO2 was described well by the pseudo-second order rate equation. The rate-determining step of the adsorption was the combined action of film diffusion and intraparticle diffusion. The adsorption thermodynamic analysis suggested ΔG0 < 0, ΔH0 > 0, and ΔS0 > 0, which indicated that the adsorption was a spontaneous and endothermic process with entropy increased.

Key words: Mesoporous TiO2, Lysozyme, Adsorption, Kinetics, Thermodynamics