ИСТИНА

Experiments have been conducted on the adsorption of trace elements on various types of rocks of lateritic weathering cores under static conditions. Results were obtained on the adsorption of trace elements as a function of pH (3, 4.5, 5.5, and 7) and on the initial concentration of the solution of 1ppm-20ppb. As adsorbents, samples of rocks of the bauxite profile (from the top downwards along the section) were used: cuirass, bauxites, laterites of transition zone. It is determined that against a background of high Al content in the solution, as a result of partial dissolution of gibbsite at pH 3, an insignificant desorption of most trace elements is observed. Significant adsorption was revealed for Ga, Sc. Almost completely at pH 4.5-7 adsorbed Be, Y, As, U, Pb, REE. Partial adsorption is observed for Co, Ni, Cu and Cd. The absorption values of V, Th, and Bi by the solid phase, regardless of the rock and the pH, were 98-100%. The experimental data are in good agreement with the accumulation of trace elements in the profile of lateritic bauxiton weathering crusts.