Process for preparing transition metal carbonates

Abstract

A process for preparing transition metal carbonates with a mean particle diameter in the range from 6 to 19 μm (D50), which comprises combining, in a stirred vessel, at least one solution of at least one transition metal salt with at least one solution of at least one alkali metal carbonate or alkali metal hydrogencarbonate to prepare an aqueous suspension of transition metal carbonate, and, in at least one further compartment, continuously introducing a mechanical power in the range from 50 to 10 000 W/l in a proportion of the suspension in each case, based on the proportion of the suspension, and then recycling the proportion into the stirred vessel.

1 . A process for preparing transition metal carbonates with a mean particle diameter in the range from 6 to 19 μm (D50), which comprises combining, in a stirred vessel, at least one aqueous solution of at least one transition metal salt with at least one aqueous solution of at least one alkali metal carbonate or alkali metal hydrogencarbonate to prepare an aqueous suspension of transition metal carbonate, and, in at least one further compartment, continuously introducing a mechanical power in the range from 50 to 10 000 W/l in a proportion of the suspension in each case, based on the proportion of the suspension, and then recycling the proportion into the stirred vessel. 
     
     
         2 . The process according to  claim 1 , wherein transition metal is selected from Cr, V, Mn, Ni, Fe, Co, Zn, Ti, Zr and mixtures of one or more of the aforementioned with one another or with alkali metal, aluminum or magnesium. 
     
     
         3 . The process according to  claim 1  or  2 , wherein transition metal carbonates are alkali metal- and hydroxide-containing transition metal carbonates. 
     
     
         4 . The process according to any of  claims 1  to  3 , wherein an overall mean power in the range from 2 to 35 W/l is introduced, based on overall suspension. 
     
     
         5 . The process according to any of  claims 1  to  4 , wherein the further compartment(s) is/are selected from pumps, inserts, mixing units, wet mills, stirred tanks and homogenizers. 
     
     
         6 . The process according to any of  claims 1  to  5 , wherein the further compartment(s) is/are connected to the stirred vessel via a pumped circulation system. 
     
     
         7 . The process according to any of  claims 1  to  6 , wherein a mean solids content of the suspension in the range from 70 to 1000 g/l is employed. 
     
     
         8 . The process according to any of  claims 1  to  7 , wherein transition metal is selected from mixtures of Ni, Mn, Co and optionally one or more further metals selected from alkali metal, aluminum and magnesium. 
     
     
         9 . The process according to any of  claims 1  to  8 , wherein precipitated transition metal carbonate is removed from the mother liquor. 
     
     
         10 . The process according to any of  claims 1  to  9 , wherein the precipitation is followed by removal of transition metal carbonate particles with a diameter greater than 50 μm. 
     
     
         11 . The process according to  claim 10 , wherein the precipitation is followed by removal of transition metal carbonate particles with a diameter greater than 32 μm. 
     
     
         12 . A transition metal carbonate in particulate form, comprising at least one transition metal carbonate selected from carbonates of Cr, V, Mn, Ni, Fe, Co, Zn, Ti and Zr, wherein the particles are essentially spherical, the proportion of particles with a diameter greater than 50 μm is less than 0.1% by weight, the mean diameter (D50) is in the range from 6 to 19 μm and the ratio of tamped density to mean particle diameter (D50) is greater than 0.08 kg/(l·μm). 
     
     
         13 . The transition metal carbonate according to  claim 12 , wherein the proportion of particles having a diameter greater than 32 μm is less than 0.1% by weight. 
     
     
         14 . The transition metal carbonate according to  claim 12  or  13 , which comprises at least two different transition metals as cations. 
     
     
         15 . The transition metal carbonate according to any of  claims 12  to  14 , which comprises Mn, Ni and Co as transition metal cations. 
     
     
         16 . The transition metal carbonate according to any of  claims 12  to  15 , wherein the transition metal cations are distributed within the particles without domain formation.