Calcium Carbonate (CaCO3) is a white powered calcium salt with a chalky taste. It is insoluble in water and is made up of carbon, oxygen and calcium. Pure carbon carbonate is found in minerals such as vaterite, aragonite and calcite which is the most stable. Naturally, It can also be found in rocks and forms such as limestone, marble, travertine and chalk globally. Industrially, pearls, snail shells, eggshells and seashells can be used as sources of calcium carbonate since they are principally made from it.
Meanwhile, oyster shells and dark green vegetables like kale and broccoli are sources of dietary this compound . It is used in the pharmaceutical industry as a calcium supplement or as an antacid which helps to neutralize acids in the stomach but can be harmful to the body if taken beyond proportion. It is also used in the construction industry, paper industry, agricultural industry amongst others.
Preparation of Calcium Carbonate
Calcium carbonate can be prepared in two ways: Ground calcium carbonate(GCC) and Precipitated Calcium Carbonate (PCC).
Ground calcium carbonate(GCC) is prepared by the extracting and processing of naturally occurring elements like limestone.
Precipitated calcium carbonate (PCC) is prepared when water is added to carbon oxide to produce carbon hydroxide which is then passed through carbon dioxide for proper precipitation.
CaO + H2O = Ca(OH)2
Ca(OH)2 + CO2 = CaCO3 + H2O
Precipitated calcium carbonate can also be produced as a by-product in the Solvay process.
Calcite which is the most polymorph of calcium carbonate is obtained in two major ways.
First, by passing carbon dioxide through slaked lime.
Ca(OH)2 + CO2 = CaCO3 + H2O
Secondly, it can be obtained by the addition of sodium carbonate into calcium chloride.
CaCl2 + Na2CO3 = CaCO3 + 2NaCl
Chemical Properties of Calcium Carbonate
When calcium carbonate undergoes a thermal decomposition reaction, it releases carbon dioxide which leads to the formation of quick lime which can also be called calcium oxide.
CaCO3 = CaO + CO2
Calcium carbonate reacts with dilute acids to release carbon dioxide which undergoes a rapid integration to CO2 and H2O
CaCO3 + 2HCl = Ca2 + H2O + CO2
It also reacts with carbon dioxide-saturated water to form calcium bicarbonate.
CaCO3 + H2O + CO2 = Ca(HCO3)2
Physical Properties of Calcium Carbonate
Carbon carbonate is a white, odourless and fluffy powder.
It is soluble in dilute acids and insoluble in water.
Its melting point is 1,339 in °C and 2,442 in °F.
It has a density of 2.711 g/cm3 and a molar mass of 100.0869 g/mol.
Uses of Calcium Carbonate
• It is used in the construction industry as a component in the production of cement, as a principal substance for building materials, in the building of roads and many other ways.
• When precipitated, it is used as white paint.
• It is used to neutralize acidic soil.
• It is used to refine sugar gotten from a beet.
• It is used in the production of toothpaste.
• It is used in the purification of iron.
• It is used to regulate alkalinity in swimming pools.
• Traditionally, it is used in the production of blackboard chalk.
• It is used for scrubbing.
• It is used as a density increaser and filter cake-sealing agent to drilling fluids in the oil industry.
• It is used for food colouring.
• In the paper industry, It is used as a paper filler and coater.
• It is used to improve the electrical and mechanical properties of PVC cables.
• In the medical industry, it is used as a calcium supplement or antacid. However, excess consumption of these supplements could lead to a toxic syndrome called the milk-alkali syndrome.
Immoderate intake of calcium could also lead to abdominal pain, vomiting and many other complications.
• It is used to regulate the alkalinity of ponds.
• It is used for firming bottled and canned products.
• It is used as a fertilizer.
Calcium is the most abundant mineral in the body and is needed in the body for proper bone and dental formation and maintenance. It also plays a huge role in the clotting of blood and many other functions.
However, its deficiency can lead to muscle contraction, pancreatitis, thin skin, sprue, renal failure etc.
In this case, calcium carbonate can be a very great option due to its functionality and affordability. It also offers 40% elemental calcium which is the highest among the calcium supplements.
However, if you have had hyperglycemia, parathyroid gland disorder, kidney diseases, or cancer then you must consult your doctor before taking this supplement because normally the dosage for people with these issues is different.
Possible side effects that might arise while taking calcium carbonate as a calcium supplement include vomiting, stomach upset, loss of appetite, constipation etc.
Meanwhile, excess calcium in your blood could lead to excessive urination, muscle weakness, fatigue, nausea, vomiting, abdominal pain and several other complications.
We recommend that you endeavor to contact your doctor, when you feel any of these symptoms just to be on the safe side.