process for the removal of low levels of trace elements and minerals contained in rocks or very poor

摘要

1,183,612. Extraction of trace elements from rocks or ores. BUREAU DE RECHERCHES GEOLOGIQUES ET MINIERES. 8 March, 1967 [8 March, 1966], No. 8897/67. Heading C2C. [Also in Division C1] Trace elements, particularly metals, contained in a rock material or an ore, may be removed without the destruction of the crystalline system of the rock material or the ore, by chelation of the trace element by treatment with at least one organic chelating agent. The rock material or ore is preferably subdivided to a suitable size to improve the contact between the chelating agent or agents and the trace elements; the chelating agent may be percolated through or agitated with the said material or ore. Specific examples describe the treatment of a rock material with a mixture of oxalic and citric acids.