Abstract: Calco-magnesian aqueous suspension having particles of solid matter with, before being put into suspension, a specific surface area, calculated according to the BET method, which is less than or equal to 10 m2/g, and its method of preparation. Such an aqueous suspension of calco-magnesian solid matter can achieve a very low viscosity, making it possible to greatly increase the solid matter concentration of the suspension, or again to reduce the size of the particles in suspension, thus obtaining a concentrated and reactive milk of lime.

Abstract: Calco-magnesian aqueous suspension having particles of solid matter with, before being put into suspension, a specific surface area, calculated according to the BET method, which is less than or equal to 10 m2/g, and its method of preparation.

Abstract: The present invention is a Ca(OH)2 particle composition and a method of making the composition, the composition consisting essentially of dried calcium hydroxide particles having a moisture content of less than 2 percent by weight of the total composition, a specific surface area greater than 30 m2/g, a total nitrogen desorption pore volume of at least 0.1 cm3/g, and a CO2 content of less than 2 percent by weight of the total composition, the aforementioned particles being in the form of a mixture comprising first fraction of particles having a size of less than 32 micrometers and a second fraction of particles of a size greater than 32 micrometers, the weight percent of the second fraction ranging from 20 to 50 percent, the aforementioned particles having a nitrogen desorption pore volume consisting of pores with a diameter ranging from 100 to 400 Angstroms.

Abstract: In the method for the humid treatment of effluents containing a compound selected from the group consisting of H.sub.2 SO.sub.4, free SO.sub.2, SO.sub.3.sup.-, or SO.sub.4.sup.= and having a pH lower than 5, the effluents are reacted with a basic compound. Particles selected from the group consisting of CaCO.sub.3.MgCO.sub.3, MgCO.sub.3 and a mixture of these, are used for treating the said effluents, the said particles having a particle size such that at least 95% of the particles selected from the group consisting of CaCO.sub.3.MgCO.sub.3 and MgCO.sub.3 have a particle size smaller than 75 .mu.m. After treatment magnesium sulfate in the form of a solution or brine is recovered.

Abstract: A dilute aqueous solution containing less than 80 g/l of magnesium hydrogen carbonate of formula Mg(HCO.sub.3).sub.2 can be used for the curative treatment of plants attacked by magnesium deficiency or preventively as complementary magnesium fertilizer and as photosynthetic activator of growth of plants by simple spraying onto them.An aqueous solution of magnesium hydrogen carbonate Mg(HCO.sub.3).sub.2 is prepared from MgO as starting material by mixing it into water and by treating the solution or suspension thus obtained with gaseous carbon dioxide, at a temperature below 40.degree. C. under a pressure greater than 5.times.10.sup.5 pascals (5 bars).

Abstract: The present invention relates to a process for the preparation of substantially spherical monocrystalline vaterite, in particular, of vaterite having a determined size.