响应面法优化聚丙烯酸/腐殖酸/累托石吸附剂的制备条件

Optimization of preparation conditions of polyacrylic acid/humic acid/ rectorite adsorbent based on response surface methodology

以累托石、丙烯酸及腐殖酸为原料制备出能同时吸附重金属和多环芳烃的吸附剂聚丙烯酸/腐殖酸/累托石,采用响应面试验设计法优化吸附剂的制备条件。利用Design Expert软件,建立了预测吸附剂对Cd2+、菲吸附量的二次回归模型,对回归模型进行了方差分析,并确定了吸附剂的最佳制备条件。结果表明,二次回归模型能较好地模拟Cd2+、菲的吸附量与影响因子丙烯酸中和度、引发剂量和交联剂量之间的关系。各因子对Cd2+吸附量的影响次序为:交联剂量>引发剂量>丙烯酸中和度;对菲吸附量的影响次序为引发剂量>交联剂量>丙烯酸中和度。吸附剂的最佳制备条件为:累托石、丙烯酸和腐殖酸三者的质量比为65∶30∶5,丙烯酸中和度、引发剂量和交联剂量分别为75.16%、2.57%和0.44%。在此优化条件下制备的吸附剂对Cd2+和菲的吸附量分别为170.19 mg/g和7.36 mg/g。

Rectorite, acrylic acid and humic acid were used to prepare polyacrylic acid/humic acid/rectorite adsorbent which can absorb heavy metal ion and PAHs in water simultaneously. Response surface methodology was adopted to optimize the conditions for preparation of the absorbent. A quadratic model was established to calculate adsorption capacity of metal ion and PAHs, and analysis of variance was performed by Design Expert. The results indicate that the quadratic model could fit the relationship between sorption capacity and factors. The order of influence on sorption capacity of Cd2＋ was as follows： cross-linker 〉 initiator 〉 neutralization degree, while the sequence on adsorption capacity of phenanthrene was initiator 〉 cross-linker 〉 neutralization degree. The maximum adsorption capacity of Cd and phenanthrene were up to 170.19 mg/g and 7.36 mg/g when ratio of rectorite, acrylic acid and humic acid was 65：30： 5, the neutralization degree was 75.16% , initiator was 2.57% , cross-linker was O. 44% , respectively.