Manufacturing Process
Magnesium hydroxide:
Magnesium hydroxide is manufactured mainly by using the Dow process, in which seawater is mixed in a flocculator with lightly burned reactive dolomite. When this is executed, an insoluble magnesium hydroxide precipitates to the bottom of a settling tank, from where it is pumped as a slurry. Finally it is dried in a series of evaporation steps until a final product of magnesium hydroxide is achieved (Britannica, 2013). There are many other ways to manufacture magnesium hydroxide (TheChemLife, 2010).
TheChemLife (Screen Name). (2012, March 23). How to make magnesium hydroxide (aka milk of magnesia). Retrieved from https://www.youtube.com/watch?v=hZaDUTX-kIs&list=PLxepWxnvFCnI15OM6LDpfwNp2iXKK1NsX
Rolaids:
The tablet form of Rolaids is made by combining calcium carbonate, magnesium hydroxide, and other inactive ingredients such as, dextrose, magnesium stearate, polyethylene glycol, and pregelatinized starch to form an antacid tablet. Finally, it is wrapped with aluminum foil and paper. |
Calcium carbonate:
Calcium carbonate, as it is used for industrial purposes, is extracted by mining or quarrying. Pure calcium carbonate can be produced from marble, or limestone. It can also be prepared by passing carbon dioxide into a solution of calcium hydroxide, forming "precipitated calcium carbonate,” or PCC (ima-na, 2011) |