An acid gas absorption composition may generally comprise calcium oxide generally characterized by a specific surface area from 40-100 m.sup.2/g, a porous volume from 0.25-0.50 cm.sup.3/g within a pore diameter range up to 1200 Angstroms, more than 40% by weight of the composition of pores having a diameter from 100-400 Angstroms, and an acid gas mass absorption capacity of at least 4.5 grams of acid gas per 100 grams of composition. Methods of making and using the same are also described.

A composition of milk of lime comprising particles of slaked lime suspended in an aqueous phase, characterised in that said particles of slaked lime have a particle size described by a particle size distribution profile that is narrow and monomodal and the method of production thereof.

A process is shown for manufacturing a milk of lime of great fineness which includes at least the steps of providing one lime compound chosen in the group consisting of prehydrated lime, a paste of lime obtained by addition of water to quicklime instead of addition of quicklime to water and their mixture, and forming a milk of slaked lime of great fineness with the chosen lime compound. The paste of lime is obtained by progressive addition of water to quicklime under agitation conditions.

A composition of milk of lime comprising particles of slaked lime suspended in an aqueous phase, characterized in that said particles of slaked lime have a particle size described by a particle size distribution profile that is narrow and monomodal and the method of production thereof.

Calcium hydroxide-containing compositions can be manufactured by slaking quicklime, and subsequently drying and milling the slaked product. The resulting calcium hydroxide-containing composition can have a size, steepness, pore volume, and/or other features that render the compositions suitable for treatment of exhaust gases and/or removal of contaminants. In some embodiments, the calcium hydroxide-containing compositions can include a D.sub.10 from about 0.5 microns to about 4 microns, a D.sub.90 less than about 30 microns, and a ratio of D.sub.90 to D.sub.10 from about 8 to about 20, wherein individual particles include a surface area greater than or equal to about 25 m.sup.2/g.

A method of providing highly reactive hydrated lime and the resultant lime hydrate where an initial lime feed comprising calcium and impurities is first ground to a particle-size distribution with relatively course particles. Smaller particles are then removed from this ground lime and the smaller particles are hydrated and flash dried to form a hydrated lime, which is then milled to a significantly smaller particle size than that of the relatively course particles.

A sorbent composition with improved acid gas reactivity comprising calcium hydroxide particles is provided. In the calcium hydroxide composition, the amount of time it takes the calcium hydroxide particles to neutralize in citric acid of a mass greater than 10 times the mass of the calcium hydroxide particles is less than 10 seconds; about 90% of the calcium hydroxide particles are less than or equal to about 10 microns; and the calcium hydroxide particles have a BET surface area of about 18 m.sup.2/g or greater.

A process is shown for manufacturing a milk of lime of great fineness which includes at least the steps of providing one lime compound chosen in the group consisting of prehydrated lime, a paste of lime obtained by addition of water to quicklime instead of addition of quicklime to water and their mixture, and forming a milk of slaked lime of great fineness with the chosen lime compound. The paste of lime is obtained by progressive addition of water to quicklime under agitation conditions.