Thermodynamic study of Zn2+ inhibition properties and mechanism on calcium carbonate precipitation by chemical and electrochemical methods
Autor: | Salah Benslimane, Kamel-Eddine Bouhidel, Hubert Perrot, Rima Bennezar |
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Přispěvatelé: | Laboratory of Chemistry & Environmental Chemistry (LCCE), University of Batna Hadj Lakhder [Algeria], Laboratoire Interfaces et Systèmes Electrochimiques (LISE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS) |
Jazyk: | angličtina |
Rok vydání: | 2016 |
Předmět: |
inorganic chemicals
General Chemical Engineering Complex formation Inorganic chemistry 02 engineering and technology Electrochemistry 020401 chemical engineering [CHIM]Chemical Sciences General Materials Science Lewis acids and bases 0204 chemical engineering Calcium carbonate precipitation Volume concentration Water Science and Technology Chemistry Precipitation (chemistry) Mechanical Engineering zinc inhibition mechanism Water thermodynamic speciation General Chemistry 021001 nanoscience & nanotechnology scaling inhibitor Experimental methods 0210 nano-technology [CHIM.OTHE]Chemical Sciences/Other Stoichiometry |
Zdroj: | Desalination Desalination, Elsevier, 2016, 398, pp.114-120. ⟨10.1016/j.desal.2016.07.013⟩ Desalination, 2016, 398, pp.114-120. ⟨10.1016/j.desal.2016.07.013⟩ |
ISSN: | 0011-9164 1873-4464 |
Popis: | In this paper, The Zn 2 + inhibition mechanism on CaCO 3 precipitation was investigated. It is well established that Zn 2 + delays the precipitation, even at very low concentrations; however, the related mechanism remains not well understood. This paper proposes a novel thermodynamic mechanism to explain the key inhibiting pre-precipitation step of Zn 2 + on CaCO 3 precipitation. It is based on the hypothesis of the Zn 2 + /OH – spontaneous complexation reaction to form ZnOH + . This OH – removal by Zn 2 + , an established Lewis acid, prevents the HCO 3 − /OH – reaction. These predictions were verified thermodynamically. It confirms the spontaneous formation and predominance of ZnOH + complex in the 7.0–9.0 pH range. This Zn 2 + inhibiting property is strengthened by other complex formation (ZnCO 3(aq) ° , Zn(CO 3 ) 2 2 − , Zn(OH) 2(aq) ° ) and by the absence of any Zn precipitate at low Zn 2 + concentrations. Furthermore, the comparison of chemical-electrochemical experimental methods clarified their differences and evidenced more the thermodynamic and stoichiometric inhibition mechanisms. |
Databáze: | OpenAIRE |
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