Anhydrous, amorphous and porous magnesium carbonates and methods of production thereof
An X-ray amorphous magnesium carbonate is disclosed that is characterized by a cumulative pore volume of pores with a diameter smaller than 10 nm of at least 0.018 cm 3 /g, and a specific surface areas of at least 60 m 2 /g. The X-ray amorphous magnesium carbonate is produced by reacting an inorganic magnesium compound with alcohol in a CO 2 atmosphere. The X-ray amorphous magnesium carbonate can be a powder or a pellet and acts as a desiccant in, for example, production of food, chemicals or pharmaceuticals.
1. A magnesium carbonate, wherein the magnesium carbonate is X-ray amorphous and is anhydrous, and wherein the magnesium carbonate has an incremental pore volume in cm 3 /g that has a maximum value of less than 0.08 cm 3 /g for pores with a diameter of 30 nm or less, and wherein the incremental pore volume is measured by nitrogen adsorption, and wherein the magnesium carbonate with pores with a diameter of 30 nm or less is 83% of the magnesium carbonate powder.
2. The magnesium carbonate according to claim 1 , wherein the magnesium carbonate with pores with a diameter of 30 nm or less has a cumulative pore volume of less than 0.4 cm 3 /g.
3. The magnesium carbonate of claim 1 , wherein the magnesium carbonate is characterized by a BET specific surface area obtained from N 2 sorption isotherms of between 60 m 2 /g and 1500 m 2 /g.
4. The magnesium carbonate of claim 3 , wherein the magnesium carbonate is characterized by a BET specific surface area obtained from N 2 sorption isotherms of between 600 m 2 /g and 1500 m 2 /g.
5. The magnesium carbonate of claim 1 , wherein the magnesium carbonate is characterized by adsorbing more than 0.3 mmol water/g material at an RH of 3% at room temperature.
6. The magnesium carbonate of claim 5 , wherein the magnesium carbonate is characterized by adsorbing more than 14 mmol water/g material at an RH of 90% at room temperature.
7. A desiccant comprising the magnesium carbonate according to claim 1 .
8. A pellet or a film comprising the magnesium carbonate according to claim 1 .
9. An additive to a food, a chemical, a cosmetic or a pharmaceutical comprising the magnesium carbonate according to claim 1 .
10. An excipient in a cosmetic or a pharmaceutical comprising the magnesium carbonate according to claim 1 .
11. A magnesium carbonate, wherein the magnesium carbonate is X-ray amorphous and is anhydrous, and wherein the magnesium carbonate has an incremental pore volume in cm 3 /g that has a maximum value of less than 0.08 cm 3 /g for pores with a diameter between 10 and 30 nm, the incremental pore volume measured by nitrogen adsorption, and wherein the magnesium carbonate with pores with a diameter between 10 and 30 nm is 80% of the magnesium carbonate powder.
12. The magnesium carbonate according to claim 11 , wherein the magnesium carbonate with pores with a diameter between 10 and 30 nm has a cumulative pore volume of 0.386 cm 3 /g.
13. The magnesium carbonate of claim 11 , wherein the magnesium carbonate is characterized by a BET specific surface area obtained from N 2 sorption isotherms of between 60 m 2 /g and 1500 m 2 /g.
14. The magnesium carbonate of claim 13 , wherein the magnesium carbonate is characterized by a BET specific surface area obtained from N 2 sorption isotherms of between 600 m 2 /g and 1500 m 2 /g.
15. The magnesium carbonate of claim 11 , wherein the magnesium carbonate is characterized by adsorbing more than 0.3 mmol water/g material at an RH of 3% at room temperature.
16. The magnesium carbonate of claim 15 , wherein the magnesium carbonate is characterized by adsorbing more than 14 mmol water/g material at an RH of 90% at room temperature.
17. A desiccant comprising the magnesium carbonate according to claim 11 .
18. A pellet or a film comprising the magnesium carbonate according to claim 11 .
19. An additive to a food, a chemical, a cosmetic or a pharmaceutical comprising the magnesium carbonate according to claim 11 .
20. An excipient in a cosmetic or a pharmaceutical comprising the magnesium carbonate according to claim 11 .