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US 11,235,982 B2Granted
Process for the preparation of an aqueous solution comprising at least one earth alkali hydrogen carbonate and its use
AssigneeOmya International AG
InventorsMatthias Buri, Samuel Rentsch, Patrick A. C. Gane, René Vinzenz Blum, Martine Poffet
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Abstract
The present invention refers to a process for the preparation of an aqueous solution comprising at least one earth alkali hydrogen carbonate and its uses.
Claims26
A process for the production of a precipitated earth alkali carbonate, the process comprising the following steps:
- (I) providing an aqueous solution comprising at least one earth alkali hydrogen carbonate, and
- (II) heating the aqueous solution comprising at least one earth alkali hydrogen carbonate of step (I) in order to obtain the precipitated earth alkali carbonate, and/or
- (III) adding at least one earth alkali hydroxide or earth alkali oxide to the solution of step (I) to obtain the precipitated earth alkali carbonate,
- wherein the aqueous solution comprising at least one earth alkali hydrogen carbonate in step (I) is obtained by the process comprising the steps of:
- a) providing water,
- b) providing at least one substance comprising at least one earth alkali carbonate, the at least one substance being in a dry form or in an aqueous form, wherein the at least one substance is selected from the group consisting of marble, limestone, chalk, dolomite, and precipitated calcium carbonate, and wherein the at least substance has a specific surface area (SSA) in the range of 0.01 to 200 m2/g, and a weight median particle size (d50) in the range of 0.1 μm to 50 μm,
- c) providing CO2,
- d) combining the at least one substance of step b) with the CO2 of step c) in the water of step a) at a temperature in a range of 5 to 55° C. in order to obtain a resulting suspension S having a pH of between 6 and 9, a solids content of in the range from 1 to 35 wt.-% based on the total weight of the resulting suspension S, and containing particles that represent a total particle surface area (SSAtotal) that is greater than 20,000 m2/tonne of the resulting suspension S,
- e) filtering at least a part of the resulting suspension S that is obtained in step d) by passing the resulting suspension S through a filtering device in order to obtain an aqueous solution comprising at least one earth alkali hydrogen carbonate.
6 more elements
A process for the production of a precipitated earth alkali carbonate, the process comprising:
- (I) providing an aqueous solution comprising at least one earth alkali hydrogen carbonate, and
- (II) heating the aqueous solution comprising at least one earth alkali hydrogen carbonate of step (I) in order to obtain the precipitated earth alkali carbonate, and/or
- (III) adding at least one earth alkali hydroxide or earth alkali oxide to the solution of step (I) to obtain the precipitated earth alkali carbonate,
- wherein the aqueous solution comprising at least one earth alkali hydrogen carbonate in step (I) is obtained by a continuous process comprising:
- combining at least one substance comprising at least one earth alkali carbonate with CO2 in water at a temperature in a range of 5 to 55° C. to obtain a resulting suspension having a pH of between 6 and 9, a solids content of from 1 to 35 wt.-% based on the total weight of the resulting suspension, and containing particles that represent a total particle surface area (SSAtotal) that is greater than 20,000 m2/tonne of the resulting suspension;
- and
- passing the resulting suspension through a filtering device to obtain the aqueous solution comprising at least one earth alkali hydrogen carbonate;
- wherein the at least one substance is selected from the group consisting of marble, limestone, chalk, dolomite, and precipitated calcium carbonate and has a specific surface area (SSA) in the range of 1.0 to 200 m2/g, and a weight median particle size (d50) in the range of 0.1 μm to 50 μm.
5 more elements
Dependencies are inferred from the claim text.