Understanding Competitive Adsorption of NTMP and Silica on Ferric Hydroxide
| Autor: | ChenYingying, FarrellJames, C BaygentsJames |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Denticity
Dissolved silica Condensation Inorganic chemistry 02 engineering and technology 010501 environmental sciences 021001 nanoscience & nanotechnology 01 natural sciences Pollution Quantum chemistry Phosphonate chemistry.chemical_compound Adsorption Membrane chemistry Environmental Chemistry Density functional theory 0210 nano-technology Waste Management and Disposal 0105 earth and related environmental sciences |
| Zdroj: | Environmental Engineering Science. 34:401-409 |
| ISSN: | 1557-9018 |
| DOI: | 10.1089/ees.2016.0441 |
| Popis: | Ferric hydroxide adsorbents are commonly used to remove phosphonate antiscalants from membrane concentrate solutions. This research investigated competitive adsorption of nitrilotris(methylenephosphonic acid) (NTMP) and silica on ferric hydroxide. Equilibrium adsorption isotherms were measured and column breakthrough and regeneration experiments were performed for an NTMP adsorbate in simulated membrane concentrate solutions with and without dissolved orthosilicic acid. Quantum chemistry simulations using density functional theory (DFT) were used to evaluate the thermodynamic favorability of possible adsorption mechanisms for NTMP and silica. Column breakthrough experiments showed that 86 mg/L of dissolved silica decreased adsorption of NTMP by 36% after 3,685 bed volumes. DFT modeling indicated that NTMP and silica adsorption on ferric hydroxide may occur through both mono- and bidentate complex formation. NTMP adsorption through a bidentate binuclear complex was 12 kcal/mol more energetically f... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|