How to produce manganese sulfate monohydrate?

With the wide application of manganese sulfate monohydrate, the production process of manganese sulfate monohydrate is gradually updated. What are the production processes of manganese sulfate monohydrate? Let’s take a look at the production process of manganese sulfate monohydrate.

1. Production process of manganese sulfate monohydrate

1. Sulfuric acid method

(1) Direct method: Concentrated sulfuric acid reacts directly with lightly burned powder (bitter soil powder) or crushed magnesite ore to obtain fertilizer grade manganese sulfate monohydrate.

(2) Indirect method: Magnesium oxide (magnesium hydroxide or magnesium carbonate) reacts with sulfuric acid to first generate a magnesium sulfate solution, crystallize and separate the heptahydrate, and then dehydrate it at high temperature to obtain manganese sulfate monohydrate.

2. Use salt lake crude magnesium sulfate heptahydrate as raw material to prepare manganese sulfate monohydrate

(1) Direct dehydration method: Crush the crude magnesium and directly dehydrate it at a high temperature above 200! to obtain crude manganese sulfate monohydrate.

(2) Recrystallization dehydration method: Dissolve crude magnesium in water, clarify and separate the water-insoluble matter, recrystallize MgSO47H2O, and then dehydrate it at high temperature to obtain manganese sulfate monohydrate. The mother liquor is returned to the system for recycling.

(3) Evaporation method: The finished product of manganese sulfate monohydrate is obtained by evaporation crystallization method.

3. Use high-temperature salt as raw material to prepare manganese sulfate monohydrate

(1) Brine re-drying method: When the temperature of seawater salt field bitter brine drops to 5, MgSO47H2O and NaCl begin to precipitate together.

(2) High-temperature salt leaching method: When seawater sun-dried salt bitter brine is evaporated using the brine mixing method, high-temperature salt is produced. Since NaCl dissolves very little and MgSO4 dissolves more, after heat preservation and clarification, the leaching solution is separated from the undissolved high-temperature salt, and then cooled to below 10°C to precipitate magnesium sulfate heptahydrate. Separate and dry at high temperature to obtain manganese sulfate monohydrate. . This method is more expensive and has fewer adopters.

(3) High and low temperature salt shaking conversion method: Use a saturated solution of magnesium sulfate (crystallization mother liquor) and high and low temperature salts to form a suspension, and then shake it in a shaking tank. The sodium chloride particles are large and dense, and they settle quickly; six water Magnesium sulfate has low density and small particles that are not easy to settle. After shaking, the sedimentation salt is separated (low-grade manganese sulfate monohydrate can be obtained by separation again).

2. Manganese sulfate monohydrate MVR evaporation method

Using the energy-saving process technology of MVR evaporator, the evaporated secondary steam is mechanically compressed and reused, which greatly reduces steam consumption and has obvious energy-saving effect.

The operation mode is continuous evaporation and crystallization. There are always crystals in the evaporator, which can inhibit the adhesion rate of calcium sulfate on the wall surface after precipitation.

The prepared manganese sulfate solution is concentrated and crystallized by evaporating water. The crystallization rate is 55%~60%. The obtained crystals are centrifuged and filtered and dried at 85°C to obtain manganese sulfate monohydrate product. At the same time, in order to avoid the enrichment of impurities in the crystallization mother liquor , the crystallization mother liquor is returned to the pre-extraction liquid, and extraction is performed again.

Manganese sulphate monohydrate in fertilizers