Calcium stearate is a white powder, insoluble in water, cold ethanol And ether, soluble in hot benzene, benzene and turpentine and other organic solvents, slightly soluble in hot ethanol and ether. It decomposes slowly when heated to 400°C and is flammable. It decomposes into stearic acid and corresponding calcium salts when exposed to strong acid and is hygroscopic.
There are four production methods for calcium stearate:
1. The synthesis of calcium stearate will have a content of 1074kg/m3 (10°Bé ) calcium chloride solution is added to the sodium stearate solution prepared above, and a metathesis reaction is performed at about 65°C, and the product calcium stearate precipitates out. Then filter, wash, and dry at about 90°C to obtain the finished product.
2. Suspend 5.60g (0.1mol) calcium oxide in 300mL, 55℃ hot water. Then dissolve 51.3g of chemically pure stearic acid in 350mL of hot water at 70°C, add 0.75g of diethanolamine, and stir to emulsify. Gradually add the prepared stearic acid emulsion to the calcium oxide suspension within 2 hours, and stir thoroughly. Filter out the formed white insoluble matter, namely calcium stearate, and dry it to obtain the product.
3. Direct method: Add a certain amount of stearic acid and CaO into a reaction pot equipped with a stirrer and thermometer, raise the temperature to melt, slowly add the catalyst H2O2 under constant stirring, and evacuate to control the reaction. The temperature is 140~150℃, and the reaction takes 1.5~2.0h. After the reaction is completed, the material is discharged, cooled, and crushed to obtain the product.
4. Metathesis method: Dissolve stearic acid in 20 times the mass of hot water, add saturated caustic soda solution, and perform saponification reaction at about 75°C to generate a dilute sodium stearate solution. Then add the calcium chloride solution with a content of 1074kg/m3 to the sodium stearate solution, conduct a metathesis reaction at about 65°C, and the product calcium stearate precipitates out. Then filter, wash, and dry at about 90°C to obtain the finished product.