Abstract:
Dialysis of humic organic matter separates the material into molecular weight fractions or, more correctly, fractions
which can pass through specifically sized pores. In the course of investigating the structure of humic organic matter in
different industrial processes, we have found some unusual properties of humic fractions from the Bayer process for
separating alumina from ferric oxide, The dialysis process appeared not to discriminate against certain small molecules
of organic matter produced from a plant operating at 250-255°C. In this paper, we demonstrate that these small
molecules appear to be bound to large molecules by physical entrapment and/or noncovalent interactions. Evidence for
this supposition is given by proton nuclear magnetic resonance and by derivatisation of polar groups, which then
releases the entrapped small molecules that can be detected and identified by gas chromatography/mass spectrometry.
A host-guest theory is proposed that may have wide ramifications into the nature of the bonding of other low molecular
weight substances to larger humic materials such as those in aqueous solutions in streams, rivers and seas.
