Alltheusedreagents(Na2CO3,NaHCO3,NaOH,HCl)wereanalytical-gradereagentsandthechemicalpropertiesofcationicsur-factantsusedinthisstudyarerepresentedinTableS1(Supplemen-taryinformation).Doubledistilledwaterwasusedforpreparingallofthesolutionsandreagents.TheinitialpHisadjustedwith0.1MHClandNaOHsolutions.Alltheadsorptionexperimentswerecarriedoutatroomtemperature(25±1°C).