摘要
以可生物降解的聚苯乙烯磺酸钠(PSS)为分散剂,制备了能稳定分散于水中的零价纳米铁(nZVI)。未改性的零价纳米铁呈规则的球形或椭球形,平均粒径为60~80 nm,经PPS分散后的纳米铁nZVI/PSS则呈现微小的粒状分散在PSS中。pH=8时,与nZVI相比,nZVI/PSS的ζ电位由+9.4 mV降至-36.7 mV,同时等电点也由8.7变为小于5。XPS分析结果显示,nZVI和nZVI/PSS表面元素构成相同,但nZVI/PSS表面有零价铁存在,而nZVI表面则主要由铁的氧化物组成。实验结果表明,两种纳米铁对Cr(VI)的去除率非常接近,在纳米铁投加量为1.0 g.L-1,Cr(VI)初始浓度为100 mg.L-1的条件下,Cr(VI)的去除率在10 min内均能达到95%,在30 min内能达99%,表明nZVI/PSS具有较高活性。
using biod Dispersed nanoscale zero-valent iron (nZVI) dispersed in water up to 2 weeks was synthesized egradable polymer Poly(sodium-p-styrenesulfonate) (PSS) as a stabilizer. The results of TEM indicated that the bare-nZVI are largely spherical or spheroidicity , with a mean partical size of 60-80 nm, while the nZVI/PSS are dispersed in a kind of crystal coat. X-ray photoelectron spectroscopy (XPS) confirmed that the surface element composition of nZVI was just the same as nZVI/PSS, the difference was that there were zerovalent iron on the nZVI while not on the nZVI/PSS. The result of zeta ( ξ)- potential showed that the X-potential of nZVI reduced from + 9.4 mV to -36.7 mV after dispersed with PSS at pH = 8. The isoelectric point (IEP) shifted from pH = 8.7 to less than 5. Batch experiments confirmed that the capacity of effectively reducing hexavalent chromium of nZVI and nZVI/PSS was equivalent. At 1 g · L^-1 iron loading and 100 mg · L^-1 initial Cr(VI) concentration , over 95% Cr(VI) was removed in less than 10 min and 99% in less than 30 min. This result indicated that the laboratory- prepared nZVI/PSS remains high reactivity.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2012年第3期526-530,共5页
Bulletin of the Chinese Ceramic Society
基金
广东省自然科学基金(No.9451064101003289
10151064101000066)
华南理工大学基本科研业务费(2011ZM0051)
教育部高校博士点基金(No.20090172120034)
关键词
零价纳米铁
聚苯乙烯磺酸钠
六价铬
nanoscale zero-valent iron
poly (sodium-p-styrenesulfonate)
hexavalent chromium