Influence ofBacillus subtilisCell Walls and EDTA on Calcite Dissolution Rates and Crystal Surface Features

2003 ◽  
Vol 37 (11) ◽  
pp. 2376-2382 ◽  
Author(s):  
A. K. Friis ◽  
T. A. Davis ◽  
M. M. Figueira ◽  
J. Paquette ◽  
A. Mucci
Keyword(s):  
Crystal Surface ◽  
Dissolution Rates ◽  
Calcite Dissolution ◽  
Surface Features

scholarly journals Estimating the activation energy of bond hydrolysis by time-resolved weighing of dissolving crystals

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Philippe Ackerer ◽  
Arnaud Bouissonnié ◽  
Raphael di Chiara Roupert ◽  
Damien Daval
Keyword(s):  
Activation Energy ◽  
Crystal Surface ◽  
Calibration Method ◽  
Solute Concentration ◽  
Bond Breaking ◽  
Dissolution Rates ◽  
Experimental Conditions ◽  
Time Resolved ◽  
Crystal Dissolution ◽  
Dissolution Model

AbstractBond-breaking activation energy EB is nowadays a key parameter for understanding and modeling crystal dissolution processes. However, a methodology to estimate EB based on classical dissolution experiments still does not exist. We developed a new method based on the calibration of a Kossel type dissolution model on measured dissolution rates obtained by mass (or volume) variations over time. The dissolution model does not depend on the geometry of the crystal surface but only on the density of the different types of sites (kink, step, terrace, bulk). The calibration method was applied to different experimental setups (flow through and batch) with different ways of estimating the dissolution rates (solute concentration in the fluid, surface topography) for calcite crystals. Despite the variety of experimental conditions, the estimated bond-breaking activation energies were very close to each other (between 31 and 35 kJ/mol) and in good agreement with ab initio calculations.

scholarly journals Cave airflow patterns control calcite dissolution rates within a cave stream: Blowing Springs Cave, Arkansas, USA

2020 ◽  
Author(s):  
Matthew Covington ◽  
Katherine Knierim ◽  
Holly Young ◽  
Josue Rodriguez ◽  
Hannah Gnoza
Keyword(s):  
Dissolution Rates ◽  
Calcite Dissolution

scholarly journals A Statistical Approach for Analysis of Dissolution Rates Including Surface Morphology

Minerals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 458 ◽  
Author(s):  
Elisabete Trindade Pedrosa ◽  
Inna Kurganskaya ◽  
Cornelius Fischer ◽  
Andreas Luttge
Keyword(s):  
Mineral Dissolution ◽  
Etch Pits ◽  
Dissolution Rates ◽  
Calcite Dissolution ◽  
Crystal Dissolution ◽  
Vertical Scanning Interferometry ◽  
Surface Morphologies ◽  
Micrometer Scale ◽  
Flow Experiments

Understanding mineral dissolution is relevant for natural and industrial processes that involve the interaction of crystalline solids and fluids. The dissolution of slow dissolving minerals is typically surface controlled as opposed to diffusion/transport controlled. At these conditions, the dissolution rate is no longer constant in time or space, an outcome observed in rate maps and correspondent rate spectra. The contribution and statistical prevalence of different dissolution mechanisms is not known. Aiming to contribute to close this gap, we present a statistical analysis of the variability of calcite dissolution rates at the nano- to micrometer scale. A calcite-cemented sandstone was used to perform flow experiments. Dissolution of the calcite-filled rock pores was measured using vertical scanning interferometry. The resultant types of surface morphologies influenced the outcome of dissolution. We provide a statistical description of these morphologies and show their temporal evolution as an alternative to the lack of rate spatial variability in rate constants. Crystal size impacts dissolution rates most probably due to the contribution of the crystal edges. We propose a new methodology to analyze the highest rates (tales of rate spectra) that represent the formation of deeper etch pits. These results have application to the parametrization and upscaling of geochemical kinetic models, the characterization of industrial solid materials and the fundamental understanding of crystal dissolution.

Results of Vertical Scanning Interferometry (VSI) of Dissolved Borosilicate Glass: Evidence for Variable Surface Features and Global Surface Retreat

2002 ◽  
Vol 757 ◽  
Author(s):  
Icenhower J.P. ◽  
Lüttge A. ◽  
McGrail B.P. ◽  
Beig M.S. ◽  
Arvidson R.S. ◽  
...  
Keyword(s):  
Reaction Mechanisms ◽  
State Theory ◽  
Dissolution Rates ◽  
Surface Features ◽  
Glass Dissolution ◽  
Variable Surface ◽  
Competing Models ◽  
A New Technique ◽  
Vertical Scanning Interferometry ◽  
Glass Compositions

ABSTRACTTwo disparate reaction mechanisms have been invoked to explain the reactivity of glass in contact with aqueous solution. One model is based on arguments from Transition State Theory (TST), which postulates that glass dissolution rates are surface reaction controlled. Alternatively, the second model argues that release of elements from glass to solution is governed by diffusion through an altered layer that forms on the surface of glass. Vertical Scanning Interferometry (VSI) is a new technique that allows one to observe surface features of specimens exposed to solution and may, potentially, be used to distinguish between competing models. We performed a series of dissolution experiments with a suite of glass compositions from chemically simple (sodium borosilicate) to complex (sixteen component borosilicate). Dissolution rates were determined using single-pass flow-through (SPFT) apparatus at 90°C and pH = 9 and over a solution saturation interval. Upon termination of the experiments, glass coupons were examined by VSI techniques. Effluent chemistry and VSI measurements indicate a nearly constant rate of 2.2 to 3.4 g m-2 d-1 over the solution interval; rates calculated from both methods are identical within experimental uncertainty. We argue that this glass is phase separated, and propose a model for dissolution based on the relative rates of dissolution of the two glass compositions. The data are consistent with a modified version of TST and indicate the potency of VSI methods to elucidate glass reaction mechanisms.

Pore-Scale Controls on Calcite Dissolution Rates from Flow-through Laboratory and Numerical Experiments

2014 ◽  
Vol 48 (13) ◽  
pp. 7453-7460 ◽  
Author(s):  
Sergi Molins ◽  
David Trebotich ◽  
Li Yang ◽  
Jonathan B. Ajo-Franklin ◽  
Terry J. Ligocki ◽  
...  
Keyword(s):  
Numerical Experiments ◽  
Pore Scale ◽  
Dissolution Rates ◽  
Calcite Dissolution ◽  
Flow Through

scholarly journals The contribution of hydrodynamic processes to calcite dissolution rates and rate spectra

2021 ◽  
Author(s):  
Priyanka Agrawal ◽  
Till Bollermann ◽  
Amir Raoof ◽  
Oleg Iliev ◽  
Cornelius Fischer ◽  
...  
Keyword(s):  
Dissolution Rates ◽  
Calcite Dissolution ◽  
Hydrodynamic Processes

Impact of Surface Reactivity on the Simulation of Mineral Dissolution Rates

2021 ◽  
Author(s):  
Jonas Schabernack ◽  
Cornelius Fischer
Keyword(s):  
Nuclear Waste ◽  
Safety Assessment ◽  
Large Time ◽  
Crystal Surface ◽  
Surface Reactivity ◽  
Mineral Dissolution ◽  
Dissolution Rates ◽  
Rate Laws ◽  
Rate Calculation ◽  
Waste Repositories

<p>The kinetics of mineral dissolution plays a key role in many environmental and technical fields, e.g., weathering, building materials, as well as host rock characterization for potential nuclear waste repositories. Mineral dissolution rates are controlled by two parameters: (1) transport of dissolved species over and from the interface determined by advective fluid flow and diffusion (transport control) and (2) availability and distribution of reactive sites on the crystal surface (surface reactivity control). Reactive transport models (RTM) simulating species transport commonly calculate mineral dissolution by using rate laws [1]. However, the applied rate laws solely depend on species concentration in the fluid. While the effect of transport-controlled processes is addressed in current RTM approaches, the intrinsic variability of surface reactivity is neglected. Experimental studies under surface-controlled dissolution conditions have shown that surface reactivity is heterogeneously distributed over the surface [e.g., 2]. This heterogeneity in reactivity is largely caused by nanotopographical structures on the crystal surface, such as steps and etch pits. These structures are generated through defects in the crystal lattice. At these structures, the high density of reactive kink sites is leading to a local increase in surface reactivity observable through high dissolution rates.</p><p>In this study, we test whether the current rate calculation approach applied in RTMs is sufficient to reproduce experimentally observed rate heterogeneities. We apply a standard RTM approach combined with the measured surface topography of a calcite single crystal [2]. Calcite is an important mineral component in the sandy facies of the Opalinus clay formation, that is under investigation for nuclear waste storage. The modeled surface dissolution rate maps are compared to experimentally derived rate maps. Results show that the current RTM is not able to reproduce the measured rate heterogeneities on the calcite surface. To improve the predictive capabilities of RTMs over the large time scales required for the safety assessment of nuclear waste repositories, the surface reactivity that is intrinsic to the mineral needs to be implemented into future rate calculations. Investigating calcite surface reactivity in the context of dissolution can also yield information about other kinetic surface processes such as the adsorption of radionuclides during transport. We show the integration of surface reactivity into rate calculation by using a proxy parameter. The slope of the crystal surface at the nm scale is applied. We show that by adding a factor based on the slope to the rate law the RTM is able to approximate experimental rate maps. Other proxy parameters such as surface roughness could yield similar results as well. The implementation of surface reactivity proxy parameters will allow for a more precise prediction of host rock-fluid interaction over large time scales in RTMs, relevant for safety assessment of nuclear waste repositories.</p><p>[1] Agrawal, P., Raoof, A., Iliev, O. and Wolthers, M. (2020), Advances in Water Resources, 136, 103480. [2] Bibi, I., Arvidson, R.S., Fischer, C. and Lüttge, A. (2018), Minerals, 8, 256.</p>

Effects of the Biologically Produced Polymer Alginic Acid on Macroscopic and Microscopic Calcite Dissolution Rates

2004 ◽  
Vol 38 (11) ◽  
pp. 3040-3046 ◽  
Author(s):  
Perry ◽  
Owen W. Duckworth ◽  
Christopher J. McNamara ◽  
Scot T. Martin ◽  
Ralph Mitchell
Keyword(s):  
Alginic Acid ◽  
Dissolution Rates ◽  
Calcite Dissolution

Calcite dissolution rates in texturally diverse calcareous rocks

2014 ◽  
Vol 406 (1) ◽  
pp. 81-94 ◽  
Author(s):  
Yael Levenson ◽  
May Schiller ◽  
Yevgeny Kreisserman ◽  
Simon Emmanuel
Keyword(s):  
Dissolution Rates ◽  
Calcite Dissolution
Sign in / Sign up

Export Citation Format

Share Document