skip to main content


This content will become publicly available on November 7, 2018

Title: Exceptional selectivity for dissolved silicas in industrial waters using mixed oxides

The removal of silica, ubiquitous in produced and industrial waters, by novel mixed oxides is investigated in this present study. We have combined the advantage of high selectivity hydrotalcite (HTC, (Mg 6Al 2(OH) 16(CO 3)·4H 2O)), with large surface area of active alumina (AA, (Al 2O 3)) for effective removing of the dissolved silica from cooling tower water. The batch test results indicated the combined HTC/AA is a more effective method for removing silica from CTW than using each of HTC or AA separately. The silica uptake was confirmed by Fourier transform infrared (FTIR), and Energy dispersive spectroscopy (EDS). Our results indicate HTC/AA effectively removes silica from cooling tower water (CTW), even in the presence of large concentrations of competing anions, such as Cl -, NO 3 - HCO 3 -, CO 3 2- and SO 4 2-. The Single Path Flow Through (SPFT) tests confirmed to rapid uptake of silica by combined HTC/AA during column filtration. The experimental data of silica adsorption fit best to Freundlich isotherm model.
 [1] ;  [1] ;  [1] ;  [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2214-7144; PII: S2214714417305093
Grant/Contract Number:
AC04-94AL85000; NA0003525
Accepted Manuscript
Journal Name:
Journal of Water Process Engineering
Additional Journal Information:
Journal Volume: 20; Journal Issue: C; Journal ID: ISSN 2214-7144
Research Org:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; dissolved silica; industrial water recycles; hydrotalcite; active alumina; water treatment
OSTI Identifier: