Calcium Hydroxide - China

Brief Overview
Calcium hydroxide does not occur naturally since it reacts readily with water (to form hydrated lime) and carbon dioxide to form limestone. This is an exothermic reaction which releases a lot of heat, thus caution must be taken. Calcium oxide vary in the degree of crystallization and cohesion of the crystalline mass and the homogeneity of the matrix.
Manufacturing Process
Method 1: Calcium carbonate is reacted with hydrochloric acid to generate calcium chloride. After which, ammonia is added for neutralization and left to stand for precipitation to occur. The solution is filtered, and sodium bicarbonate is added to generate a calcium carbonate precipitate.
Method 2: Calcium carbonate is heated to a higher temperature to undergo thermal decomposition to form calcium oxide or burnt lime. Calcium oxide is then treated or slaked with water to produce calcium hydroxide on a commercial scale:
CaO + H2O → Ca(OH)2
The calcium oxide is broken down into fine particles of calcium hydroxide in this hydration reaction, which occurs in a continuous hydrator. The particle sizes can be modified through milling to ensure consistent particle size.