·
Linear Formula Ca(OH)2
·
Molecular Weight 74.09
Calcium hydroxide, traditionally called slaked lime,
is an inorganic compound with the chemical formula Ca(OH)2.
It is a colorless crystal or white powder and is obtained when calcium oxide (called lime or quicklime)
is mixed, or "slaked" with water.
Detailed description
It
has many names including hydrated lime, caustic lime, builders'
lime, slack lime, cal, or pickling lime.
Calcium hydroxide is used in many applications, including food
preparation. Limewater is the
common name for a saturated solution of calcium hydroxide.
Uses
One significant application of calcium hydroxide is
as a flocculant, in water
and sewage treatment.
It forms a fluffy charged solid that aids in the removal of smaller particles
from water, resulting in a clearer product. This application is enabled by the
low cost and low toxicity of calcium hydroxide. It is also used in fresh water
treatment for raising the pH of the water so that pipes will not corrode where
the base water is acidic, because it is self-regulating and does not raise the
pH too much.
It is also used in the preparation of ammonia gas,
using the following reaction:
Ca(OH)2 + 2NH4Cl → 2NH3 +
CaCl2 + 2H2O
Another large application is in the paper industry,
where it is an intermediate in the reaction in the production of sodium
hydroxide. This conversion is part of the causticizing step in
the Kraft process for making
pulp.[8] In the
causticizing operation burned lime is added to green liquor which
is a solution primarily of sodium carbonate and sodium sulfate produced by
dissolving smelt, which is the molten form of these chemicals from
the recovery furnace.
Food industry
Because of its low toxicity and the mildness
of its basic properties, slaked lime is widely used in the food industry to:
·
process water for
alcoholic beverages and soft drinks
·
make corn tortillas: it
helps the corn flour (masa) bind together (see nixtamalization)
·
clear a brine of carbonates of calcium
and magnesium in the manufacture of salt for food and pharmaceutical
uses
·
aid digestion (called
Choona, used in India in paan, a mixture of areca nuts, calcium hydroxide and
a variety of seeds wrapped in betel leaves)
Native American uses
In Spanish, calcium hydroxide is called cal.
Corn cooked with cal (nixtamalization) becomes hominy (nixtamal), which significantly
increases the bioavailability of niacin, and it is also considered tastier and
easier to digest.
In chewing coca leaves, calcium hydroxide
is usually chewed alongside to keep the alkaloid stimulants chemically
available for absorption by the body. Similarly, Native Americans traditionally
chewed tobacco leaves with calcium hydroxide derived from burnt mollusk shells
to enhance the effects. It has also been used by some indigenous American
tribes as an ingredient in yopo, a psychedelic snuff
prepared from the beans of some Anadenanthera species.[10]
Asian uses
Calcium hydroxide is typically added to a bundle
of areca nut and betel leaf to keep the alkaloid stimulants chemically
available to enter the bloodstream via sublingual absorption.
Afghan uses
It is used in making naswar (also known as nass or niswar),
a type of dipping tobacco made from fresh tobacco leaves, calcium hydroxide (chuna),
and wood ash. It is consumed most in the Pathan diaspora, Afghanistan, Pakistan, India, Bangladesh and also
in Sweden and Norway. Villagers also use calcium hydroxide to paint
their mud houses in Afghanistan, Pakistan and India.
PRICE
$94.86/KG OR $43.11/IB
For more information:
mobile: +2348039721941
contact person: emeaba uche
e-mail: emeabau@yahoo.com
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