TWO-STAGE METHOD FOR OBTAINING METAL TIN (II) CARBOXYLATES Russian patent published in 2019 - IPC C07C51/41 C07C51/42 C01G19/00 

FIELD: chemistry; metallurgy.

SUBSTANCE: invention relates to a two-step process for the preparation of tin (II) carboxylates based on direct interaction of a metal with an acid in the absence or in the presence of an oxidizing agent, where the process is carried out at a temperature of 15–25 °C in a bead mill with a high-speed mixer and a grinding agent in a mass ratio with loading (except metal) 1:1, in the first stage glass beads are used as a grinding agent, the metal in an amount by weight of 7.42–20.01 % of the rest loading is brought into contact with an aqueous solution of nitric or hydrochloric acid with a concentration of 0.25–2.50 mol/kg taken in a metal:acid (1.01:1)÷(5.05:1) molar ratio, in the absence or presence of up to 0.25 mol/kg of ammonium salt additives and (0÷121)⋅10^-3 mol/kg of copper-containing oxidant under conditions of reliable contact of a well-stirred reaction mixture with air flowing through the gas space of the reactor and oxidation is carried out with the control over the accumulation of tin (II) compounds until the loaded metal is completely consumed or the process is automatically stopped for another reason, followed by separation of the grinding agent and unreacted metal, by filtering suspended product, washing the precipitate with water and further drying in air to constant weight or to an intermediate state with further loading some part thereof after drying immediately or through any non-fixed period of time as the beginning of the second stage into a bead mill with ferro-aluminium high-resistance alloy as a grinding agent, organic solvent, molar content of carboxylic acid and (3–15)⋅10^-3 mol/kg tribochemical catalyst multiple of (2.05–2.30) in relation to the loading of compounds of tin (II), carrying out the second stage with the current control over the course of acid consumption until the latter stops, after which the process is stopped, the grinding agent is separated from the product suspension, the latter is isolated by filtration, washed with solvent on the filter from excess acid, removed from the filter, dried and stored before use, or sent for additional purification by recrystallization.

EFFECT: two-stage process for the preparation of metal tin (II) carboxylates is proposed.

6 cl, 10 tbl, 38 ex