Abstract:

:Claymineralsarewidelydistributedinsoilsandsedimentaryrocks.Thesurfacewettabilityofclaymineraliscloselyrelated toprimarypetroleummigrationinargillaceoussourcerocks,andmobilityoforganicpollutantinsoils.Aimingatinvestigatingthe influencesofsurfacewettabilityofclaymineralsontheprimarymigrationofhydrocarbon,thisstudyconstructsslitporeswithwallsof kaoliniteandillitebasalsurface.Thespatialdistributionofwaterandorganicmattersintheporesystemshasbeenrevealedusing moleculardynamicssimulations.Thedifferenceinwettabilityofclaymineralinpurewaterandinsalinewaterhasbeendisclosed. Differentbehaviorsofhydrocarbon,alcohol,andbenzenehavealsobeenrevealed.Itisindicatedthatthebasalsurfaceofillitealways presentshydrophilicaswellsiloxanesurfaceofkaoliniteishydrophobicandhydroxylsurfacehydrophilic.ThepresenceofNaClalters hydrophobicsiloxanesurfaceintototallyhydrophilic.Inaddition,theorganicmatterwithpolargroupstendstobeadsorbedonto hydrophilicclaysurfacealthoughthesemoleculesaggregatetogetherintheporewater,whichleadstotheirdifferentdistribution.

Key words: wettability;moleculardynamicssimulation;claymineral;slitpore