The difference between magnesium sulfate monohydrate and magnesium sulfate heptahydrate

The difference between magnesium sulfate monohydrate and magnesium sulfate heptahydrate has always been a difficult problem for users. In fact, one obvious difference between the two (feed additive magnesium sulfate) is their appearance. Magnesium sulfate monohydrate is a white powder solid, while magnesium sulfate heptahydrate is a colorless and transparent crystal.

From a chemical perspective, magnesium sulfate monohydrate is a hydrated magnesium sulfate containing one crystalline water, while magnesium sulfate heptahydrate has seven crystalline water. Therefore, for magnesium sulfate monohydrate and magnesium sulfate heptahydrate of the same quality, the percentage of magnesium element in magnesium sulfate monohydrate is 1.78 times that of magnesium sulfate heptahydrate. Because of this, in agricultural production, magnesium sulfate monohydrate has a higher effective magnesium content than magnesium sulfate heptahydrate.

In large-scale industrial production, the raw materials for both magnesium sulfate monohydrate and magnesium sulfate heptahydrate are sulfuric acid and magnesium oxide. However, the products produced by the same process are also mixed in quality. This is because some unscrupulous manufacturers choose cheap industrial waste acid as the raw material to produce magnesium sulfate heptahydrate, in order to reduce production costs. However, this practice has great hidden dangers, which requires analysis from the source of industrial waste acid.

The main sources of industrial waste acid are in the fields of metallurgy and electroplating, and a large amount of acid is used in the process of metal surface treatment. When the metal samples and other impurities in the acid solution reach a certain concentration and the treatment effect cannot meet the process requirements, the acid solution needs to be recombined and replaced. During this process, a large amount of waste acid liquid will be generated. These waste acids contain high concentrations of acid, as well as heavy metal elements such as cobalt, titanium, chromium, arsenic, and various inorganic impurities. Once such industrial waste acid enters the next production process without treatment, its products will be contaminated.

Once such heptahydrate magnesium sulfate products are used in agricultural production, they will have a negative impact on the soil they are sprayed on. The acid ions and toxic heavy metals carried by impurity acids in industrial waste acids will accumulate in the soil, animals and plants, and the result will be absorbed by the human body.

Compared to magnesium sulfate heptahydrate, the situation of using waste acid as raw material for magnesium sulfate monohydrate is more optimistic. Due to the inherent properties of magnesium sulfate monohydrate, if waste acid is used as the raw material, the product will appear gray black instead of normal milky white, and the color difference directly determines the product's appearance. Therefore, most manufacturers of magnesium sulfate monohydrate prefer industrial sulfuric acid over industrial waste acid.

As an important component of aquatic feed and a core element in magnesium supplement compound fertilizer, the quality of magnesium sulfate is related to the quality of the entire product. For many agricultural enterprises such as feed and fertilizer, choosing a high-quality and stable magnesium sulfate supplier is a prerequisite to ensure the overall quality of the product.