Process for the preparation of an aqueous solution comprising at least one earth alkali hydrogen carbonate and its use

A process for the preparation of an aqueous solution comprising at least one earth alkali hydrogen carbonate, 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 one substance 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,
• 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 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, and
• 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.