Abstract The swelling and cation exchange properties of montmorillonite are fundamental in a wide range applications ranging from nanocomposites to catalytic cracking hydrocarbons. results several factors and, though widely studied, information on the effects single factor at time is lacking. In this study, density functional theory (DFT) calculations were used obtain atomic-level montmorillonite. Molecular dynamics (MD) was investigate montmorillonites with different layer charges...

Abstract Green chemistry, sustainability and eco-efficiency are guiding the development of next generation industrial chemical processes. The use non-edible lignocellulosic biomass as a source chemicals fuels has recently raised interest due to need for an alternative fossil resources. Valorisation mainly focuses on cellulose, which been used various scale applications decades. However, creating economically more viable value chain would require exploitation other main components,...

A surface complexation model of Se(IV) sorption on biotite with one type strong sites and two types weak were developed based experimental data obtained from titration, edge isotherm experiments. Titration was collected using a batch-wise manner together backtitration to calibrate the effect mineral dissolution in 0.01 M KClO 4 background electrolytes pH 3 11 an inert atmosphere glovebox. Further calibrations titration curve include proton exchange cation which calculations occupancies...

Ab initio methods were used to study the coordination of electron donors (110) and (101) surfaces a MgCl2 support. The alcohols, ketones, esters, their model compounds. Examination interaction energies indicated that alcohols bind more strongly five-coordinated magnesium atom on surface than four-coordinated surface. This stability can be explained in terms hydrogen bonding between complexed alcohol chloride ion Like esters form most stable complexes In contrast, ketones coordinate...

Novel coating materials are constantly needed for current and future applications in the area of microelectronics, biocompatible materials, energy-related devices. Molecular layer deposition (MLD) is answering this cry an increasingly important method organic hybrid organic–inorganic thin films. In study, we have focused on inorganic–organic coatings, based trimethylaluminum, monofunctional aromatic precursors, ring-opening reactions with ozone. We present MLD processes, where films produced...

To determine the diffusion and sorption properties of radionuclides in intact crystalline rocks, a new electromigration device was built tested by running with I- Se(IV) ions. By introducing potentiostat to impose constant voltage over studied rock sample, can give more stable accurate experimental results than those from traditional devices. In addition, variation pH background electrolytes minimised adding small amount NaHCO3 as buffers. interpret confidence, an advection-dispersion model...

Abstract MX-80 bentonite colloids’ effect on radionuclide sorption was studied by batch method and transport in flow using a granitic drill core column Sr(II) as radionuclide. Batch-type desorption experiments were conducted to determine Sr(II)’s distribution coefficients colloids metatexitic gneiss. Molecular modeling assessed the radionuclide’s affinity justified differences behavior biotite versus montmorillonite. The found be hundred times greater for than rock. Strontium’s breakthrough...

A computational fluid dynamics (CFD) model was developed for fouling of calcium phosphate in heat exchangers which can consider the tendency components to precipitate and surface properties materials. In CFD precipitation inversely soluble mineral due temperature increase near-surface region heated wall modeled based on saturation ratio. The precipitates form small, spherical particles that adhere surface. function adherence modified turbulent viscosity by CFD. tested against experiments...

Abstract Fouling caused by inversely soluble salts, like CaCO3, is a general problem on heat transfer surfaces. Carbonate depositions are typically cleanable with acids, but costs of energy losses, operation, and maintenance significant. In this study, formation CaCO3 was investigated cristobalite, diamond, titanium carbide The aim the study to clarify detailed mechanisms crystallization fouling during initiation crystalline phases existing in materials used as coatings (SiOx, TiCN,...

Molecular modeling is a novel approach in the field of fouling research. A method was used to calculate reactions and molecular level interactions between heat transfer surface flowing fluid. The focus on comparison reaction mechanisms Ti(OH)4 Si(OH)4 rutile (101) surface. calculated energies indicate strong chemical bonding via condensation titanium(IV) hydroxyls weak hydrogen silanols without composition structural properties layers from real process were characterized. On surfaces,...

Abstract Potassium cobalt hexacyanoferrate(II) [K 2 CoFe(CN) 6 ] is an extremely selective ion exchanger for cesium ions. To examine the atomic level background selectivity a computational structural study using DFT modelling was carried out K and products where Cs has replaced in elemental cube cages closest to surface. In K-form compound potassium ions are not center of Co–Fe–CN elementary surface but locate about 140 pm from towards When exchanged these they much deeper surface, being...

Fouling reduces the thermal efficiency of heat transfer units, and it causes economic losses has a marked effect on CO2 releases thus climate change. In order to improve energy efficiency, deposition formation (precipitation crystallization) onto surfaces is going be mitigated. A way achieve this goal development new surface materials with controlled chemical composition morphology. study, mechanism CaCO3 depositions was investigated modified (–CH3 –COOH) organosilicon (SiOC), anatase rutile...