Nucleation-Growth Process of Scale Electrodeposition Influence of the Supersaturation

A conductive transparent electrode is used to observe and quantify the nucleation-growth process of scale deposition. The deposition is accelerated by increasing the interfacial pH induced by an electrochemical reaction on the electrode surface. Three measurements were simultaneously obtained with respect to time. The chronoelectrogravimetric and chronoamperometric curves showed that an increase of the supersaturation in the vicinity of the electrode increased the rate of scale deposition. This result was highlighted in the first instants of deposition when overlapping of crystals was not predominant. The third measurement was the in situ observation by a microscope through the transparent electrode. It allowed the count of crystals and the surface of the individualized crystals to be measured vs. time. It was shown that the increase of the local concentration of calcium and carbonate ions had no influence on the growth rate of both varieties of crystal present on the electrode surface, namely, vaterite and calcite. On the contrary, the count of the particles showed that the increase of the kinetic of scale deposition was only due to the enhancement of the nucleation rate. Thus, for the lowest investigated supersaturation, the number of nuclei increased linearly with time, whereas the highest supersaturation promoted a faster nucleation rate and a higher proportion of calcite. © 2003 The Electrochemical Society. All rights reserved.

[1]  M. Keddam,et al.  An Electrochemical Method for Testing the Scaling Susceptibility of Insulating Materials , 2001 .

[2]  B. Tribollet,et al.  Nucleation-Growth Processes of Scale Crystallization under Electrochemical Reaction Investigated by In Situ Microscopy , 2001 .

[3]  H. Cachet,et al.  In situ Investigation of Crystallization Processes by Coupling of Electrochemical and Optical Measurements: Application to CaCO 3 Deposit , 2001 .

[4]  Yuping Zhang,et al.  The kinetics of carbonate scaling—application for the prediction of downhole carbonate scaling , 2001 .

[5]  C. Gabrielli,et al.  Investigation of electrochemical calcareous scaling: Nuclei counting and morphology , 2001 .

[6]  M. Euvrard,et al.  A cell to study in situ electrocrystallization of calcium carbonate , 2000 .

[7]  J. J. García-Jareño,et al.  Influence of Water Composition and Substrate on Electrochemical Scaling , 2000 .

[8]  B. Tribollet,et al.  Characterization of calcareous deposits in artificial sea water by impedances techniques: 2-deposit of Mg(OH)2 without CaCO3 , 2000 .

[9]  Claude Gabrielli,et al.  Nucleation and growth of calcium carbonate by an electrochemical scaling process , 1999 .

[10]  M. Keddam,et al.  Quartz Crystal Microbalance Investigation of Electrochemical Calcium Carbonate Scaling , 1998 .

[11]  R. Dawe,et al.  Kinetics of calcium carbonate scaling using observations from glass micromodels , 1997 .

[12]  A. Karabelas,et al.  Morphology and Structure of CaCO3 Scale Layers Formed under Isothermal Flow Conditions , 1997 .

[13]  B. Tribollet,et al.  Interfacial pH measurement during the reduction of dissolved oxygen in a submerged impinging jet cell , 1997 .

[14]  M. Keddam,et al.  Characterization of the efficiency of antiscale treatments of water. Part II: Physical processes , 1996 .

[15]  M. Keddam,et al.  Estimation of the deposition rate of thermal calcareous scaling by the electrochemical impedance technique , 1996 .

[16]  J. Christoffersen,et al.  Kinetics of spiral growth of calcite crystals and determination of the absolute rate constant , 1990 .

[17]  B. Scharifker,et al.  Three-dimensional nucleation with diffusion controlled growth: Part I. Number density of active sites and nucleation rates per site , 1984 .

[18]  M. Y. Abyaneh,et al.  The electrocrystallisation of nickel , 1981 .

[19]  G. H. Nancollas,et al.  Kinetics of growth of calcium sulfate crystals at heated metal surfaces , 1980 .

[20]  D. Chin,et al.  Mass Transfer to an Impinging Jet Electrode , 1978 .