physical and chemical properties:
blue green monoclinic crystals or particles, odorless. weathering in dry air and oxidizing to brown alkaline iron sulfate on the surface in humid air. it becomes a tetrahydrate at 56.6 ℃ and a monohydrate at 65 ℃. soluble in water, almost insoluble in ethanol. its aqueous solution oxidizes slowly in air when cold, and oxidizes quickly when hot. adding alkali or exposure to light can accelerate its oxidation. it is stimulating. ferrous sulfate monohydrate is a light yellow or grayish white powder, anhydrous ferrous sulfate is a white powder, and crystals containing crystalline water are light green crystals, commonly known as "green alum". when dissolved in aqueous solution, they are light green.
① adjusting soil acidity and alkalinity in agriculture can promote the formation of chlorophyll (also known as iron fertilizer) and prevent yellowing disease caused by iron deficiency in flowers and trees. it is an essential element for acid loving flowers and trees, especially for iron trees.
in agriculture, it can also be used as a pesticide to prevent and control wheat smut, apple and pear scab, and fruit tree decay; it can also be used as fertilizer to remove moss and lichen from tree trunks.
② the environmental protection industry is used for sewage treatment; used for flocculation and purification of water, as well as removal of phosphates from urban and industrial wastewater to prevent eutrophication of water bodies.
③ reducing agent: a large amount of ferrous sulfate is used as a reducing agent, mainly to reduce chromates in cement.
④ medicinal use: ferrous sulfate is used to treat iron deficiency anemia; it is also used to add iron to food, and long-term excessive use may cause side effects such as abdominal pain and nausea. medically, it can also be used as a local astringent and blood tonic.
a. the production of tannic acid iron ink and other inks requires the use of ferrous sulfate. the mordant used for wood dyeing also contains ferrous sulfate.
b. ferrous sulfate can be used to stain concrete with a yellow rust color.
c. woodworking uses ferrous sulfate to give maple a silver color.
⑥ used as raw materials for manufacturing other iron salts, magnetic iron oxide, iron oxide red and iron blue inorganic pigments, iron catalysts, and polyferric sulfate. in addition, it is also used as a chromatographic analysis reagent, etc. food grade is used as a nutritional supplement, such as iron fortifier and fruit and vegetable coloring agent.
⑦ used as a mordant, tanning agent, wood preservative and disinfectant, and in photography and plate making.
⑧ feed and raw materials used as nutritional supplements, synthesis of hemoglobin in the body, and food coloring agents;
adding ferrous sulfate to feed can effectively prevent and treat low pigmented small cell anemia in animals caused by widespread iron deficiency. prevent and treat animal diseases such as iron deficiency induced mental instability, shoulder bone edema, breathing difficulties, impaired body function, uncontrolled temperature regulation, and abnormal body temperature, improve the survival rate of livestock and poultry, promote the growth and development of livestock and aquatic animals, enhance disease resistance, and increase feed returns. pigs suffering from iron deficiency anemia have impaired immune function, which controls the production of antibodies and leads to a decrease in the body's resistance. if lactating piglets do not receive fe supplementation within 4 weeks of age, their susceptibility to bacterial endotoxin lethal effects increases.