Home – Home – Jornals – Chemistry for Sustainable Development 2006 number 3

Chemical modification of oxidized and weathered coals from the Shubarkol field (Kazakhstan) is studied. Coals are shown to be fit for the synthesis of amine derivatives via their interaction with amines (diamines) in the presence of acidic catalysts. Physical and chemical analysis data support the suggested synthesis scheme. Conductometric analysis method is developed for determining the functional composition of the oxidized coal modification products. It is demonstrated that nitrogen introduction into the coals improves their complexing ability and makes them polyampholyte. Sorption capacity of amine derivatives as pH function is shown to be a parabola with minimum at pH 4-5. This fact confirms the polyampholyte nature of these agents. Amino modified coals may be used for demineralization of mine waters and as extracting agents for metal ions precipitation from hydrometallurgy wastewaters.