DRYING AGENT AND METHOD OF MAKING SAID DRYING AGENT Russian patent published in 2012 - IPC C01F7/44 

FIELD: chemistry.

SUBSTANCE: invention can be used to dry gases. The aluminium oxide-based drying agent contains the following, wt %: χ-Al₂O₃ and an X-ray amorphous phase - 35-95; γ-Al₂O₃ and η-Al₂O₃ - 5-65, has pore volume 0.25-0.6 cm³/g, effective average pore diameter 2.5-10 nm and specific surface area 200-400 m²/g, wherein the specific surface area of micropores with diameter less than 2 nm ranges from 100 to 300 m²/g. To obtain the drying agent, a product of centrifugal thermal activation of hydrargillite and/or thermochemical activation of hydrargillite is hydrated in an alkaline or acidic medium, dried, ground, plasticised and the obtained paste is extrusion moulded, dried and annealed in a current of dry air. Hydration of the ground product in an alkaline or acidic solution is carried out with intense stirring and liquid to solid ratio from 1 to 4 for 4-8 hours. Hydration of the non-ground product in alkaline or acidic solution is carried out in a ball mill with liquid to solid ratio from 1 to 2 for 4-24 hours. The extruded articles are annealed for 2-6 hours at 350-600°C, volume rate of feeding air equal to 1000-10000 h^-1, and rate of heating to annealing temperature equal to 20-50°C/h.

EFFECT: high dynamic capacity of the adsorbent-drying agent.

19 cl, 1 tbl, 16 ex