马尾松松针对磺胺二甲基嘧啶的吸附特性

以马尾松松针为吸附剂,研究其对水中磺胺二甲基嘧啶的吸附特性。考察了磺胺二甲基嘧啶的初始浓度为10 mg·L-1、温度为25 ℃时松针吸附剂饱和吸附量及饱和吸附时间,分析了温度、pH值对其吸附能力的影响,研究了吸附过程的动力学和热力学特点,并进行了相应的分析和计算。实验结果表明,在实验条件下,松针对磺胺二甲基嘧啶的吸附在 35 min达到饱和,其饱和吸附量为 0.229 mg·g-1。经准一级动力学方程拟合出的 qe为 0.24 mg·g-1与实验所得值0.229 mg·g-1接近,且相关系数R2=0.998 1,说明准一级动力学模型能较好地描述松针对磺胺二甲基嘧啶的吸附行为,且满足Langmuir 等温吸附模型。分析表明,松针对磺胺二甲基嘧啶的吸附行为为单分子层的自发吸附,且以物理吸附为主。

Adsorption characteristics of pine needles of Pinus massoniana Lamb for sulfadimidine

The adsorption characteristics of the prepared masson pine needles,which were used as biological adsorbents for sulfadimidine in water,were studied.An initial solution with a sulfadimidine concentration of 10 mg·L-1 and temperature of 25 ℃ was investigated to determine the saturated adsorption capacity and time for adsorption by the pine needles.The influence of factors,such as temperature and pH,on the adsorption capacity was analyzed; characteristics of the dynamics and thermodynamics in the adsorption process were studied; and corresponding analysis and calculation were performed.The experimental results showed that it took approximately 35 minutes for saturated adsorption of the pine needles with sulfadimidine,and the adsorption capacity was 0.229 mg·g-1 under the experimental conditions.The adsorption behavior (kinetics) of pine needles for sulfadimidine could be interpreted by the linear fitting of pseudo-first-order kinetics because the experimental saturated adsorption capacity was 0.229 mg·g-1,which approximated the calculated value (qe=0.24 mg·g-1),and the line correlation coefficient was R2=0.998 1.In addition,the adsorption thermodynamics were adopted to the Langmuir isotherm adsorption model.Analysis of the experimental results showed that the adsorption of sulfadimidine by pine needles was spontaneous and mainly occurred by a monolayer adsorption process and physical adsorption.