STUDY OF THE HUMIC-LIKE COMPOUNDS FORMED FROM L-TYROSINE ON HOMOIONICCLAYS

The ability to produce humic-like polymeric compounds, with L-tyrosine as the starting material, was evaluated using different mineral syste ms, e.g. on Ca-, Al-and Cu(II)-saturated montmorillonite, nontronite a nd kaolinite, and on quartz. Clay minerals proved to be effective in t he formation of these compounds, but not quartz, except in the presenc e of Cu(II). The newly formed compounds were fractionated by alkaline extraction. With clay systems, the amounts of substances produced appe ar to be related more to the interlayer cation than to the clay type. Copper cations appear to be more effective when not associated with th e clay structure.