2种核桃果皮炭粉吸附去除Cu 2+的动力学研究

Kinetic Study on the Removal of Cu^(2+) by Two kinds of Powdered Carbon Derived from Walnut Peel

以核桃外果皮为原料,制备了未提取水溶性混合物的炭粉(WTQC)和已提取水溶性混合物的炭粉(YTQC)2种吸附剂。通过静态吸附试验,研究了接触时间、投加量、温度以及pH对2种吸附剂吸附去除Cu^(2+)的影响和吸附过程的动力学机理。结果表明,WTQC和YTQC分别在30 min、45 min基本达到吸附平衡,2种吸附剂的最佳吸附pH范围为3~5.7,吸附过程更符合准二级动力学模型,并且在投加量浓度分别为2.5g/L/和2g/L时,WTQC和YTQC对Cu^(2+)的去除率最高,WTQC对Cu^(2+)的去除率显著高于YTQC。试验表明,这两种炭粉对Cu^(2+)的去除率高,吸附效果好,是一种制备工艺简单,廉价易得的吸附剂。

Walnut peel was used as precursor to prepare two powdered carbon such WTQC(in which water-soluble mixture didn’t been extracted)and YTQC(in which water-soluble mixture had been extracted)as adsorbents.The effect of contact time,dosage,temperature and pH on the removal of Cu 2+for two adsorbents and the dynamic mechanism of adsorption process were investigated by static adsorption test.The results showed that WTQC and YTQC almost reached at equilibrium in 30 min and 45min,respectively.The optimum pH range is 3~5.7 and the adsorption process was in accord with pseudo-second-order equation for two kinds of adsorbents.WTQC had the highest removal rate of Cu 2+at the dosage of 2.5 g/L/whereas the dosage of 2 g/L for YTQC.WTQC was significantly higher than that of YTQC on the removal rate of Cu 2+.It was indicated that the two kinds of powdered carbon have good adsorption effect for high removal rate of Cu 2+,and which are cheap and easy to be obtained with simple preparation process as adsorbents.