摘要
研究了海藻酸钠浓度及固化时间对海藻酸钠-聚氧化乙烯(SA-PEO)凝胶球性能的影响以及采用SA-PEO凝胶球对溶液中3种重金属离子(Pb2+、Cu2+、Cd2+)进行吸附实验的研究。结果表明,2.0%(质量分数)的SA溶液制成的凝胶球性能较好,固化时间对重金属去除率影响较小,但随着固化时间的增加,SA-PEO凝胶球的直径逐渐缩小,紧密程度和机械强度逐渐增加;在重金属离子溶液pH为4～6时,SA-PEO凝胶球对重金属离子去除率较高;SA-PEO凝胶球对不同重金属离子吸附效果为Pb2+>Cu2+>Cd2+;多种重金属离子共存使得SA-PEO凝胶球对Pb2+和Cd2+的吸附受一定程度的抑制,而对Cu2+吸附能力有所增强,说明SA-PEO凝胶球对重金属离子吸附有选择性;1.00mol/L的HCl溶液对Pb2+的解吸效果较好,解吸再生后的SA-PEO凝胶球可以重复利用。
The granular sodium alginate-polyethylene oxide （SA-PEO） gel adsorbent was prepared by mixing a SA solution in 0.1% PEG solution （2 ： 1 volume ratio） and then adding a small amount of 5% CaCl2 before a period of immobilization to form the adsorbent granules. The effects of SA concentration and immobilization time on the adsorbent characteristics were determined based on its adsorptive capacities for three heavy metals （Pb^2＋ ,Cu^2＋ ,Cd^2＋）. The most effective adsorbent was prepared with 2.0% SA, and a longer immobilization time resulted in a slightly more effective adsorbent for lead removal. The adsorbent was more effective when it was employed in the pH range of 4-6. A longer time of contact, up to 4-6 h, resulted in a higher capacity for each metal. The effectiveness of SA-PEO adsorbent for metal removal followed the order of Pb^2＋〉Cu^2＋ 〉Cd^2＋. The adsorbent＇s capacity for Pb and Cd was not significantly reduced by the presence of the other two metals; however, its capacity for Cu increased when Pb and Cd were also present. The adsorbent was effectively regenerated by 1.00 mol/L HC1; the regenerated adsorbent was reusable for metal removal although with a slightly reduced capacity for the target metal （Pb）.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2008年第3期50-53,共4页
Environmental Pollution & Control
基金
国家博士后基金资助项目(No.LRB05-335)
关键词
海藻酸钠
聚氧化乙烯
吸附
再生
sodium alginate
polyethylene oxide
adsorption
regeneration
