物理化学学报 >> 2016, Vol. 32 >> Issue (3): 638-646.doi: 10.3866/PKU.WHXB201512181

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介孔TiO2对溶菌酶吸附的动力学和热力学

洪启亮1,董依慧1,庄伟2,饶超1,刘畅1,*()   

  1. 1 南京工业大学, 材料化学工程国家重点实验室, 南京 210009
    2 南京工业大学生物与制药学院, 南京 211816
  • 收稿日期:2015-09-14 发布日期:2016-03-04
  • 通讯作者: 刘畅 E-mail:changliu@njtech.edu.cn
  • 基金资助:
    国家重点基础研究发展计划项目(2013CB733501);国家自然科学基金(21136004, 21476106, 21506090);江苏省自然科学基金(BK20130929);江苏高校优势学科建设工程项目

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 E-mail:changliu@njtech.edu.cn
  • 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

摘要:

773.15 K下焙烧二钛酸(H2Ti205)制备了介孔结构TiO2。采用比表面分析仪(BET)、扫描电镜(SEM)、拉曼(Raman)光谱和X射线衍射(XRD)仪进行表征研究了介孔TiO2对溶菌酶的吸附行为和机理。结果表明,该吸附过程较好地满足Langmuir吸附模型;随着溶液pH值的增高,溶菌酶在介孔TiO2上的吸附量先增大后减小。在pH = 7.2时,达到最大吸附容量72.5 mg·g-1。该介孔TiO2对溶菌酶具有良好的吸附稳定性,经过5次循环后吸附的溶菌酶残余量仍有81.6%。动力学研究表明,介孔TiO2与溶菌酶间的吸附满足准二级动力学模型,吸附传质过程由膜扩散和粒内扩散共同影响与控制。对热力学参数的计算发现,该过程ΔG0 < 0, ΔH0 > 0, ΔS0 > 0,表明介孔TiO2对溶菌酶的吸附是一个自发的、吸热的熵增过程。

关键词: 介孔TiO2, 溶菌酶, 吸附, 动力学, 热力学

Abstract:

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

MSC2000: 

  • O647