Manganese dichloride tetrahydrate, also called Manganese chloride tetrahydrate, is a chemical compound with the formula MnCl₂.4(H₂O). It is a kind of pink solid, and it has two types of α type (colorless monoclinic crystal) and β type(colorless cubic crystalline). With the CAS register number 13446-34-9, the tetrahydrate is the most common form of "manganese(II) chloride". In addition, its IUPAC name is dichloromanganese tetrahydrate. What's more, it should be sealed and stored in cool, dry and well-ventilated place.

Properties: Manganese dichloride tetrahydrate will dehydrate a molecule of water at 106 °C, and dehydrate all of the water at 198 °C. It is soluble in water and acetic acid, but insoluble in diethyl ether. Manganese dichloride tetrahydrate is stable, and incompatible with moisture, strong acids, sodium, potassium, zinc.

Preparation: this chemical can also be prepared by rhodochrosite and superfluous hydrochloric acid. The mixture reacts completetly in the reactor and then add lime to neutralize superfluous hydrochloric acid, besides, you should control the PH value around 4. After that, you can remove iron using hydrogen peroxide and remove calcium by manganese sulfate. At last, you can gain Manganese dichloride tetrahydrate via evaporation, filtration, concentration, cooling crystallization and centrifugation.

MnCO₃ + 2 HCl → MnCl₂ + H₂O + CO₂
Fe²⁺-e[H₂O₂] → Fe³⁺
CaCl₂ + MnSO₄ → MnCl₂ + CaSO₄↓

Additionally, pyrolusite is reduced by pulverized coal to generate manganese monoxide, or pyrolusite directly react with hydrochloric acid. After filtration, concentration,cooling crystallization and centrifugation, you can gain Manganese dichloride tetrahydrate. The reaction equations are as the following:

MnO₂ + C → MnO + CO
MnO₂ + CO → MnO + CO₂
MnO + 2 HCl → MnCl₂ + H₂O或
MnO₂ + 4 HCl → MnC1₂ + 2 H₂O + C1₂↑

Uses: The Manganese dichloride tetrahydrate is used as a catalyst for paint driers and gas seismic agent raw materials. It is used to feed auxiliary agents, analytical reagents, dyes and pigments manufacturing, aluminum smelting, brown-black brick and tile production, as well as the manufacture of pharmaceutical and dry. Trace elements in agriculture is also used as a fertilizer and can be used for acidic soil basic fertilizer, and top-dressing or a foliage spray.

When you are using Manganese dichloride tetrahydrate, you should be very cautious about it. There will be a danger of serious damage to health by prolonged exposure if swallowed. In case of accident or if you feel unwell seek medical advice immediately (show the label where possible). Besides, this chemical is harmful to aquatic organisms. When you are using it, you must avoid release to the environment. Besides, you can refer to special instructions/safety data sheet when you need.

Descriptors computed from structure of Manganese dichloride tetrahydrate:
(1)Canonical SMILES: O.O.O.O.Cl[Mn]Cl
(2)InChI: InChI=1S/2ClH.Mn.4H2O/h2*1H;;4*1H2/q;;+2;;;;/p-2
(3)InChIKey: CNFDGXZLMLFIJV-UHFFFAOYSA-L

The toxicity data is as follows: