【摘要】 用锆氧基离子与果胶反应制得果胶锆凝胶球,采用扫描电镜和红外光谱初步表征了凝胶球的结构,并测定了凝胶球的机械强度。研究了该凝胶球对苯甲酸的吸附性能。分别考察了果胶浓度、锆氧基离子浓度、吸附时间、p H值、温度及苯甲酸浓度对吸附性能的影响。结果表明,在298K下,果胶锆凝胶球对苯甲酸的吸附在4.5h左右达到平衡,当果胶的质量分数为3.0%,锆氧基离子质量分数为1.0%,苯甲酸初始浓度为500mg/L,吸附量可达73.89mg/g。所研究的吸附体系既适用于Freundlich方程,又适用于Langmuir方程;吸附过程为自发的放热、熵减过程,降低温度对吸附更有利。更多还原

【Abstract】 Pectin zirconium gel microsphere was synthesized by crosslinking pectin with zirconium oxygen ion, and characterized by scanning electron microscopy, Fourier transform infrared spectra and mechanical strength. The adsorption performance of pectin zirconium gel microsphere for benzoic acid was investigated. The influence of several parameters, such as adsorption time, p H, pectin concentration, zirconium oxygen ion concentration, temperature and benzoic acid concentration, on adsorption capacity were studied. The results showed that the adsorption equilibrium could be established in about 4.5h at 298 K. The adsorption capacity of 73.89mg/g was achieved when the concentration of benzoic acid was 500mg/L, the mass ratio of pectin was 3.0%, and the mass ratio of Zr O2+ was 1.0%. The adsorption system could be described by either Freundlich equation or Langmuir equation. The adsorption was a spontaneously exothermic process with entropy decreasing. Lower temperature was favourable for the adsorption.更多还原