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Magnesium Sulphate in Nairobi, Kenya

What is Magnesium Sulphate?

Magnesium sulfate or magnesium sulphate is a chemical compound, a salt with the formula MgSO
consisting of magnesium cations Mg2+
(20.19% by mass) and sulfate anions SO2−
It is a white crystalline solid, soluble in water but not in ethanol.

The main use of magnesium sulfate is in agriculture, to correct soils deficient in magnesium. Magnesium is a key component of chlorophyll. Without magnesium, the plant cannot produce chlorophyll, which will cause photosynthesis to suffer. Magnesium also plays a role in the transfer and production of sugars, starches, fats, and oils within the plant. This means a lack of magnesium will cause starchy vegetables, sugary fruits, and oil seeds or nuts to lose their shape and flavor. The anhydrous form and several hydrates occur in nature as minerals, and the salt is a significant component of the water from some springs.

Uses of Magnesium Sulphate


Magnesium sulfate is used both externally (as Epsom salt) and internally.

The main external use is the formulation as bath salts, especially for foot baths to soothe sore feet. Such baths have been claimed to also soothe and hasten recovery from muscle pain, soreness, or injury. Potential health effects of magnesium sulfate are reflected in medical studies on the impact of magnesium on resistant depression and as an analgesic for migraine and chronic pain.Magnesium sulfate has been studied in the treatment of asthma preeclampsia and eclampsia.

Magnesium sulfate is the usual component of the concentrated salt solution used in isolation tanks to increase its specific gravity to approximately 1.25–1.26. This high density allows an individual to float effortlessly on the surface of water in the closed tank, eliminating as many of the external senses as possible.

In the UK, a medication containing magnesium sulfate and phenol, called “drawing paste”, is useful for small boils or localized infections and removing splinters.

Internally, magnesium sulfate may be administered by oral, respiratory, or intravenous routes. Internal uses include replacement therapy for magnesium deficiency,treatment of acute and severe arrhythmias,as a bronchodilator in the treatment of asthma, preventing eclampsia,a tocolytic agent and as an anticonvulsant.


In agriculture, magnesium sulfate is used to increase magnesium or sulfur content in soil. It is most commonly applied to potted plants, or to magnesium-hungry crops such as potatoes, tomatoes, carrots, peppers, lemons, and roses. The advantage of magnesium sulfate over other magnesium soil amendments (such as dolomitic lime) is its high solubility, which also allows the option of foliar feeding. Solutions of magnesium sulfate are also nearly pH neutral, compared with the slightly alkaline salts of magnesium as found in limestone; therefore, the use of magnesium sulfate as a magnesium source for soil does not significantly change the soil ph. Contrary to the popular belief that magnesium sulfate is able to control pests and slugs, helps seeds germination, produce more flowers, improve nutrient uptake, and is environmentally friendly, it does none of the purported claims except for correcting magnesium deficiency in soils. Magnesium sulfate can even pollute water if used in excessive amounts.

Food preparation

Magnesium sulfate is used as a brewing salt in making beer. It may also be used as a coagulant for making tofu.


Anhydrous magnesium sulfate is commonly used as a desiccant in organic synthesis owing to its affinity for water and compatibility with most organic compounds. During work-up, an organic phase is treated with anhydrous magnesium sulfate. The hydrated solid is then removed by filtration, decantation, or by distillation (if the boiling point is low enough). Other inorganic sulfate salts such as sodium sulfate and calcium sulfate may be used in the same way.


Magnesium sulfate is used to prepare specific cements by the reaction between magnesium oxide and magnesium sulfate solution, which are of good binding ability and more resistance than Portland cement. This cement is mainly adopted in the production of lightweight insulation panels. Weakness in water resistance limits its usage.

Magnesium (or sodium) sulfate is also used for testing aggregates for soundness in accordance with ASTM C88 standard, when there are no service records of the material exposed to actual weathering conditions. The test is accomplished by repeated immersion in saturated solutions followed by oven drying to dehydrate the salt precipitated in permeable pore spaces. The internal expansive force, derived from the rehydration of the salt upon re-immersion, simulates the expansion of water on freezing.

Magnesium sulfate is also used to test the resistance of concrete to external sulfate attack (ESA).


Magnesium sulfate heptahydrate is also used to maintain the magnesium concentration in marine aquaria which contain large amounts of stony corals, as it is slowly depleted in their calcification process. In a magnesium-deficient marine aquarium, calcium and alkalinity concentrations are very difficult to control because not enough magnesium is present to stabilize these ions in the saltwater and prevent their spontaneous precipitation into calcium carbonate.


Ecofarm Africa Connections Limited is the leading supplier of Magnesium Sulphate in the Kenyan Market and across the borders. Call us today on 0714 690 266 to place your order.

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