1. It can be used as a raw material for the production of calcium carbonate.
2. Calcium hydroxide is alkaline, therefore it can be used to reduce soil acidity, thus improving soil structure. Bordeaux mixture, a pesticide, is prepared by mixing lime milk (calcium hydroxide dissolved in water) and copper sulfate solution in a certain proportion. In winter, trees are coated with lime slurry up to a depth of 80 cm above the roots to prevent insect infestation.
3. High-quality calcium hydroxide is mainly used in the production of epichlorohydrin and propylene oxide.
4. It can be used in rubber and petrochemical additives. For example, in the petroleum industry, it is added to lubricating oil to prevent coking, sludge deposition, neutralize and prevent corrosion.
5. It is used in the production of bleaching powder, bleaching agent, disinfectant, acid neutralizer, astringent, water softener, soil acidification inhibitor, depilatory, buffer, neutralizer, and curing agent.
6. Calcium hydroxide can also react with carbon dioxide in the air to form calcium carbonate, which is insoluble in water. In sugar production, calcium hydroxide is first used to neutralize the acid in the syrup. Then, carbon dioxide is introduced to react with the remaining calcium hydroxide, forming a precipitate that is filtered out, thus reducing the sour taste of the sugar.
7. Because slaked lime (Ca(OH)2) is the cheapest alkali, it is widely used. Since slaked lime (Ca(OH)2) has twice the volume of quicklime (CaO), it can be used to split wood and rock. Slaked lime-a type of mortar-was used in architectural structures as early as ancient Greece. The mortar sets due to: ① the evaporation of excess water; ② the absorption of water by bricks or cement blocks; ③ the formation of CaCO3 from the reaction of slaked lime and CO2 in the air, which adheres to and embeds between the sand grains, thus creating a strong and porous structure.
