镁盐改性石英砂的制备及其吸附Zn^2＋影响因素

摘要

In order to improve the efficiency of adsorption,quartz sand was modified with the chemical and physical methods.In this experiment quartz sand was chosen as a carrier to be coated by magnesium salt with the deposition process at alkaline condition,and then the adsorption capability and influencing factors for zinc removal by magnesium salt modified sand were investigated respectively.The experimental results showed that the specific surface area of magnesium salt modified sand was 1.475 m2/g,and it was 6.12 times of raw quartz sand.Under the condition of pH value 7.00,the removal of Zn2＋ by raw quartz sand was approximately 41%,in contrast,the removal efficiency reached 54% by magnesium salt modified sand.The adsorption effects of magnesium salt modified sand was better than raw quartz sand.It was also found that the removal rate of Zn2＋ by the magnesium salt modified sand reduced with the increase of initial concentration of Zn2＋.And the removal rate of Zn2＋ enhanced with the increase of pH value,with the Zn2＋ removal of almost 95% under the condition of pH value 9.0.%通过改变石英砂表面的物理化学性质,提高滤料的吸附效率,并考察其对废水中Zn2＋的去除效果。以石英砂为载体,用碱性沉积法制备了镁盐改性砂,测定了镁盐改性砂的比表面积,考察了镁盐改性砂对锌的吸附性能及其影响因素。结果表明,镁盐改性砂的比表面积为1.475 m2/g,比石英原砂比表面积提高了6.12倍;在pH值为中性的条件下,石英原砂对Zn2＋去除率为41%,镁盐改性砂对Zn2＋去除率可达到54%;镁盐改性砂的吸附效果优于石英原砂;随着Zn2＋初始浓度的增大,镁盐改性砂对Zn2＋的去除率逐渐减少;pH值是影响Zn2＋吸附的主要因素,随着pH值增加,吸附效果提高,当pH值接近9时,镁盐改性石英砂的Zn2＋去除率达到95%左右。