Study on the effect of reaction temperature on the structure and crystal shape of basic magnesium carbonate

The present invention discloses the method of producing alkaline magnesium carbonate. Crude hydrazine preparation step, from the reaction of urea liquid and sodium hypochlorite in the reactor to produce hydrazine hydrate, the temperature of crude hydrazine in the reactor at 100 degrees -110 degrees, the by-products include sodium chloride and sodium carbonate; distillation step, without cooling, the high temperature crude hydrazine into the evaporation system heating distillation of water, to get distilled crude hydrazine; precipitation step, in the distillation of crude hydrazine added magnesium chloride, so that In the precipitation step, magnesium chloride is added to the distilled crude hydrazine, so that magnesium chloride reacts with sodium carbonate in the crude hydrazine to produce precipitate; in the separation step, the precipitate is separated by a separator to obtain precipitate and separation liquid; in the preparation of alkaline magnesium carbonate step, the precipitate obtained in the separation step is washed with industrial water or steam condensate, pulped, and prepared by pyrolysis to produce alkaline magnesium carbonate.

The results showed that the relationship between the reaction temperature and the number of crystalline water and the crystal shape of the basic magnesium carbonate was The products prepared at 55~60℃ contained about 5 water of crystallization, and the crystal shape was needle-like; the products prepared at 65~70℃ contained 6 water of crystallization, and the crystal shape was flocculent flake; the products prepared at 75~80℃ contained about 8 water of crystallization, and the crystal shape was cotton stick-like; the products prepared at 85℃ contained 6~7 water of crystallization, and the crystal shape transitioned from cotton stick-like fracture to spherical shape; the products prepared at 90~95℃ contained The product prepared at 90-95 ℃ contained 4 crystalline waters and the crystal shape was spherical; the product prepared at 100b ℃ contained about 3 crystalline waters and the spherical structure was destroyed.