Adsorption of Molecules onto (10(1)over-bar4) Dolomite Surface: An Application of Computational Studies for Microcalorimetry

作者：Escamilla Roa Elizabeth^*; Ignacio Sainz Diaz C; Javier Huertas F; Hernandez Laguna Alfonso

来源：Journal of Physical Chemistry C, 2013, 117(34): 17583-17590.

DOI：10.1021/jp404529e

Dolomite (CaMg(CO3)(2)) is a sedimentary mineral that is found in the majority of natural carbonate rocks. Dolomite has been used in the treatment of polluting agents, and as a potential adsorbent of CO2. Dolomite is usually associated with oil deposits. Secondary oil recovery is a problem related to the adsorption processes of hydrocarbons onto rocks covering the rock surface as a film. The aim of the present study is to investigate the adsorption processes of water and several organic molecules (hexane, cyclohexane, cyclohexene, and benzene) onto the most stable (10 (1) over bar4) dolomite surface by means of Density Functional Theory (DFT) calculations for microcalorimetry applications. One molecule was adsorbed per surface, and different adsorption configurations were explored. Adsorption energy (AE) of water was 16.27 kcal/mol, whereas the AE of the different organic compounds investigated ranged between 3.14 and 5.00 kcal/mol, being much lower than water due to the lack of H bonding and electrostatic interactions that are present in the adsorption of water. Surface tension (sigma) was calculated in all adsorption complexes. The difference of a between the pristine surface and the adsorption complexes was correlated with the experimental enthalpy of immersion, finding a good agreement.

• 出版日期2013-8-29