Zhu Hui-jie, Jia Yong-feng, Yao Shu-hu, Wu Xing, Wang Shu-ying
Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
Huan Jing Ke Xue. 2009 Dec;30(12):3562-7.
A new adsorbent, activated carbon impregnated with nano zero-valent iron was prepared, which size of the needle-shaped iron particles in the pores of carbon was (30-500) nm x (1000-3000) nm and approximately 8.2% of iron was loaded onto it. The arsenate removal percentage was 99.5% by 1.5 g/L NZVI/AC in the 2 mg/L arsenic solution at pH 6.5 and (25 +/- 2) degrees C. The adsorption capacity was about 15.4 mg/g when equilibrium concentration was 1.0 mg/L. Kinetics revealed that uptake of arsenate ion by NZVI/AC was 91.4% in the first 12 h and equilibrium time was about 72 h. The intraparticle diffusion model was applied to study the mechanics of arsenate in the activated carbon. The presence of phosphate and silicate could significantly decrease arsenate removal while the effects of the other anions and cations on the arsenic removal were neglectable. NZVI/AC can be effectively regenerated when elution is done with 0.1 mol/L NaOH solution. Our results suggest that NZVI/AC is a suitable candidate for drinking water treatment due to its high reactivity.
制备了一种新型吸附剂——负载纳米零价铁的活性炭，碳孔中针状铁颗粒的尺寸为(30 - 500)nm×(1000 - 3000)nm，铁负载量约为8.2%。在pH值为6.5、温度为(25±2)℃的2mg/L砷溶液中，1.5g/L的纳米零价铁/活性炭对砷酸盐的去除率为99.5%。当平衡浓度为1.0mg/L时，吸附容量约为15.4mg/g。动力学研究表明，纳米零价铁/活性炭在最初12小时内对砷酸根离子的摄取率为91.4%，平衡时间约为72小时。采用颗粒内扩散模型研究了活性炭中砷酸盐的吸附机理。磷酸盐和硅酸盐的存在会显著降低砷酸盐的去除率，而其他阴离子和阳离子对砷去除的影响可忽略不计。用0.1mol/L的氢氧化钠溶液洗脱时，纳米零价铁/活性炭可有效再生。我们的研究结果表明，由于其高反应活性，纳米零价铁/活性炭是饮用水处理的合适候选材料。
