skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on January 1, 2017

Title: Sulfate Separation by Selective Crystallization with a Bis-iminoguanidinium Ligand

One simple and effective method for selective sulfate separation from aqueous solutions by crystallization with a bis-guanidinium ligand, 1,4-benzene-bis(iminoguanidinium) (BBIG), is demonstrated. The ligand is synthesized as the chloride salt (BBIG-Cl) by in situ imine condensation of terephthalaldehyde with aminoguanidinium chloride in water, followed by crystallization as the sulfate salt (BBIG-SO4). Alternatively, BBIG-Cl is synthesized ex situ in larger scale from ethanol. Furthermore, the sulfate separation ability of the BBIG ligand is demonstrated by selective and quantitative crystallization of sulfate from seawater. These ligands can then be recycled by neutralization of BBIG-SO4 with aqueous NaOH and crystallization of the neutral bis-iminoguanidine, which can be converted back into BBIG-Cl with aqueous HCl and reused in another separation cycle. Finally, 35S-labeled sulfate and β liquid scintillation counting are employed for monitoring the sulfate concentration in solution. Overall, this protocol will instruct the user in the necessary skills to synthesize a ligand, employ it in the selective crystallization of sulfate from aqueous solutions, and quantify the separation efficiency.
Authors:
 [1] ;  [2] ;  [3]
  1. Univ. of Texas, Austin, TX (United States). Dept. of Chemistry
  2. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemistry
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Division
Publication Date:
OSTI Identifier:
1325430
Grant/Contract Number:
AC05-00OR22725
Type:
Accepted Manuscript
Journal Name:
Journal of Visualized Experiments
Additional Journal Information:
Journal Volume: 115; Journal Issue: 115; Journal ID: ISSN 1940-087X
Publisher:
MyJoVE Corp.
Research Org:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY crystallization; separations; guanidinium; self-assembly; sulfate; water