Simultaneous adsorption of MIB and NOM onto activated carbon: II. Competitive effects

The adsorption of an odour compound common in drinking water, 2-methylisoborneol (MIB), was studied on six activated carbons in the presence of six well-characterised natural organic matter (NOM) solutions. It was found that, although the carbons and the NOM solutions had a wide range of characteristics, the major competitive mechanism was the same in all cases. The low-molecular-weight NOM compounds were the most competitive, participating in direct competition with MIB for adsorption sites. Equivalent background compound calculations indicated a relatively low concentration of directly competing compounds in the NOM. Some evidence of pore blockage and/or restriction was also seen, with microporous carbons being the most affected by low-molecular-weight NOM and mesoporous carbons impacted by the higher-molecular-weight compounds.