Physico-chemical characteristics of peat oxidative degradation products

The increased interest in the properties and methods of producing of fulvic-like acids from natural caultibolites, including primarily various peat, is caused by the appearance in their structure of compositions that provide the ability to complex formation with rare earth and heavy metals, including uranium demanded in nuclear power. The use of these fulvic-like acids in developing new technologies for the extraction of rare and heavy metals is considered to be very promising. The proposed article provides a comparative analysis of the physical and chemical properties of fulvic-like acids obtained by oxidative decomposition of peat and the humic substances of the initial peat.

Analysis of IR spectroscopy data of the initial peat (lowland and upland) and products of their oxidation with hydrogen peroxide showed that in the process of oxidative destruction occurs the breakdown of the polystranded structures of the peat with the formation of products with high content of carbonyl groups, that promote complex formation.

It was found that the oxidative destruction of peat leads to a reduction in carbon content and an increase in hydrogen and oxygen, as well as a decrease in the optical density of their solutions and an increase in solubility. The obtained molecular-mass distribution on Sephadex G-50 of initial humic acids acids and fulvic-like acids showed that destruction processes lead to a decrease in molecular weights of macromolecules of fulvic-like acids compared to the original humic acids.

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