Application of polymer-modified nanoporous silica to adsorbents of uranyl ions

作者：Jung Yonju; Kimb Seok; Park Soo Jin; Kim Ji Man^*

来源：Colloids and Surfaces A: Physicochemical and Engineering Aspects , 2008, 313: 162-166.

DOI：10.1016/j.colsurfa.2007.04.087

• nanoporous silicas (MSU-H)
• uranyl ions (UO22+)
• carboxymethylated polyethyleneimine (CMPEI)
• polyethyleneimine (PEI)
• polyacrylic acid (PAA)

The surface modification of nanoporous silicas (MSU-H) of submicron-scale particle size with polyethyleneimine (PEI), polyacrylic acid (PAA), and carboxymethylated polyethylenei mine (CMPEI) was carried out for the extraction of uranyl ions. Adsorption behaviors of uranyl ions onto the polymer-modified silicas, denoted as PEI/MSU-H, PAA/MSU-H and CMPEI/MSU-H, were examined in batch experiments. In 0.05 mM UO22+ solution, it was found that the nearly complete removal of uranyl ions can be achieved by the CMPEI-modified MSU-H (CMPEI/MSU-H). Especially, the CMPEI/MSU-H exhibited significantly high distribution coefficient value (K-d = 2.30 x 10(6)). In concentrated UO22+ solution (ca. I mM), uranium-uptake capacities onto the three polymer-modified nanoporous silicas were in the following order: CMPEI/MSU-H>PAA/MSUH>PEI/MSU-H. It is noteworthy that CMPEI/MSU-H showed excellent uranium-uptake capacity (124mg-U/g-adsorbent), based on the total weight of polymer and silica. In addition, the loading stability of uranium on the adsorbent was examined with time. It was observed that about 15% of uranium was discharged from CMPEI/MSU-H in a day and additional 5% uranium was released with a relatively slow desorption rate in 12 days.

• 出版日期2008-2-1