Process for control of microbial contamination, mineral suspensions obtained and their uses

摘要

The invention concerns a process for disinfection and/or conservation and/or reduction and/or control of microbial contamination of aqueous dispersions and/or aqueous suspensions of mineral matter, providing satisfactory stability in terms of Brookfield™ viscosity for the said aqueous dispersions and/or suspensions of mineral matter. It also concerns the said aqueous dispersions and/or suspensions thus obtained, together with their uses in the mineral, paper and paint industries. Finally it concerns the end products obtained.

主权项

1. An aqueous suspension of mineral matter comprising calcium carbonate, at least one dispersing agent, and an antimicrobial agent consisting of one or more OH− ion donors selected from alkali oxides and alkali hydroxides, wherein the aqueous suspension is obtained by a process for disinfecting or preserving the aqueous suspension of or from microbial contamination, wherein the process comprises:
a) at least one stage to increase and maintain the OH− ion concentration of the aqueous suspension of the mineral matter comprising calcium carbonate, to a value greater than or equal to 1×10−2 mole/l, by addition of the antimicrobial agent consisting of one or more OH− ion donors selected from alkali oxides and alkali hydroxides, for a sufficient time to disinfect or preserve the aqueous suspension of the mineral matter comprising calcium carbonate of or from microbial contamination, and b) at least one stage of dispersion and/or grinding of the aqueous suspension of the mineral matter comprising calcium carbonate, occurring before, during or after stage a), wherein the aqueous suspension of mineral matter has a microbe concentration of less than or equal to 100 microbes/gram.