蛭石吸附及解吸锌离子特性研究

Study on Adsorption and Desorption Properties of Vermiculite to Zinc

用蛭石对锌离子的吸附解吸进行了实验研究,初步探讨了其对锌离子吸附解吸的机理。研究结果表明:蛭石对Zn2+具有较强的吸附能力,吸附在8 h左右接近平衡。随着锌离子浓度的增加,蛭石的吸附量也在逐渐增加,当锌离子浓度达到400 mg/L时,吸附量趋于平稳。在完成吸附实验的基础上,分别采用过滤和取上清液的方法解吸,实验证明静置平衡后,取出上清液50 ml,再加入50 ml解吸剂的方法解吸效果较好;解吸时间在0 h到12 h,蛭石的解吸量呈现递增的趋势,且达到1.070 mg/g;在12 h到48 h内,解吸量基本没有增加,其中在24 h时达到最大解吸量1.074 mg/g。不同的解吸剂对蛭石解吸锌离子影响效果不同:蒸馏水不能使锌离子解吸;K+的影响作用相对于Na+更明显,随着两种阳离子浓度的增加,蛭石的解吸量逐渐增加。

With vermiculite to the zinc ions adsorption and desorption were studied, and adsorption mechanism of vermiculite had been preliminarily studied with its structure in the paper. The results showed that vermiculite to zinc ions have a strong absorption eapaeity and it was close to balance with about 8 h. With the increase of the concentration of zinc ions, adsorption of vermiculite was also gradually increase,when the eoneentration of zinc ions was 400 mg/L, the absorption capaeity had stabilized. On the basis of adsorption, two methods of filtration and extracting supematant fluid were used. Experiment proved that when the system was static balance, we can finish the desorption by extracting 50 ml supernatant fluid and then adding 50 ml desorption agent When the time was 0 h to 12 h, desorption capacity was gradually increase and achieved 1. 070 mg/g. When it was 12 h to 48 h, the capacity was stableand achieved the peak of 1. 074 mg/g at 24 h. Different desorption agents had different effeets on vermiculite to the zinc ions desorption： distilled water could not make zinc ions be desorption; The impact of K ^＋ to vermiculite desorption of zinc ions was more obvious than Na ^＋ ; along with two of the cation concentration, the desorption amount of vermiculite rised.