Magnesium Sulphate

Description

Magnesium sources

Magnesium is found in large amounts in magnesium-containing minerals such as magnesite and dolomite.

There is also some solution in seawater and oceans that causes hardness in the water.

Method of production of magnesium sulfate

The most common method of producing magnesium sulfate is

the direct reaction of a dilute solution of sulfuric acid with the mineral magnesite (mineral magnesium carbonate).

In this method, the powdered magnesite is poured into an anti-acid reaction tank containing a dilute solution of sulfuric acid with water and stirred well.

Increasing the temperature using hot steam can increase the speed and efficiency of dissolution.

During this reaction, magnesium slowly begins to dissolve in the acid and a solution of magnesium sulfate is produced.

                                                                        MgCO₃(s) + H₂SO₄(l) → MgSO₄(l) + CO₂(g) + H₂O(l)

After dissolving the magnesium in the acid, the resulting solution is suspended to separate the insoluble matter.

It is filtered by a filter press and if there are disturbing cations, They are refined and separated by sediments.

The resulting solution will contain pure magnesium sulfate, which after condensation,

in special baths (usually made of polyethylene) will turn into seven-crystal magnesium sulfate crystals.

It is also possible to dry the solution directly using a spray dryer and obtain a white powder of dry magnesium sulfate.

Magnesium sulfates available in the Iranian market are usually crystalline and contain 14-13% of the element magnesium.

Less is also dry and is marketed with about 20% magnesium.