Copper Sulphate

Primarily used for agricultural purposes such as pesticide, germicide, feed additive, and soil additive. Some of its secondary uses are as a raw material in the preparation of other copper compounds, as a reagent in analytic chemistry, an electrolyte for batteries and electroplating baths, and in medical practice as a locally applied fungicide, bactericide, and astringent.

Synonyms
Blue Vitriol (pentahydrate), Bluestone (pentahydrate), Copper Sulphate Pentahydrate, Copper (II) Sulphate Pentahydrate
Chemical Formula
CuSO4; CuSO4.5H2O
CAS Number
7758-98-7 (pentahydrate)

Characteristics

Molar Weight
159.61 g/mol (anhydrous); 249.67g/mol (pentahydrate)
Melting Point
110°C (anhydrous)
Boiling Point
650°C (decomposes)
Density
3.60 g/cc ((anhydrous); 2.286 g/cc (pentahydrate)
Forms
Crystalline

Uses and Applications

Key applications

  • Dyes
  • Plastics and polymers
  • Fungicide
  • Water treatment
  • Agricultural
  • Solvents
  • Batteries
  • Animal feed
  • Electronics
  • Paint and Coatings
  • Zinc ore / mining

Copper sulphate

Copper sulphate is the copper salt of sulphuric acid. It belongs to the sulphate group of substances.
In nature, copper sulphates are formed by the weathering and oxidation of sulphidic copper minerals (e.g. chalcopyrite or bornite) under the influence of oxygen, water and sulphuric acid, which is often released from sulphidic ores. Copper sulphates are mainly formed in dry areas as they are water-soluble and are easily washed out in humid environments.
The mineral chalcanthite is the naturally occurring form of copper sulphate pentahydrate, which forms bright blue crystals. It is formed in areas such as: Chile, Arizona (United States) and Namibia. Brochantite is a basic copper sulphate that often occurs in oxidised copper ores. It has a green to emerald green colour and is found in copper deposits worldwide.
Copper sulphate does not occur naturally in its pure, anhydrous form.

Copper sulphate in the industry

Copper sulphate is often used in agriculture to combat fungal diseases. It is used in the form of the so-called Bordeaux mixture (copper sulphate and lime) to combat mould, mildew and other fungal infections on various crops such as vines, fruit trees, tomatoes and potatoes. Copper sulphate acts as a contact fungicide, killing fungi directly before they can penetrate the plants.
It is also used to remedy copper deficiencies in the soil, as copper is an essential trace element for plants. Copper sulphate is also used as a source of copper in livestock farming. Its antimicrobial effect also plays a role in animal nutrition.
In the energy industry, copper sulphate is used in battery technology, among other things. It is used in the production of copper cathodes for lithium-ion batteries in particular.
Copper sulphate is also used as a component of corrosion inhibitors to extend the service life of systems and infrastructure in the energy industry. It is also required in certain electrochemical processes for hydrogen production.
Copper sulphate is used in the construction industry primarily due to its fungicidal, algicidal and antimicrobial properties. For example, it protects wood from fungal infestation and insects and removes mould, algae and moss on roofs, facades and pavements or prevents their growth. It also protects bricks and concrete from biological infestation by fungi and mosses.
Copper sulphate is also used as a raw material for the production of green or blue pigments, which are used in paints or coatings for construction projects.
Copper sulphate is mainly used in water treatment to control algae in ponds, reservoirs and other stagnant water. In industrial and agricultural irrigation systems, copper sulphate is needed to control algae and other deposits that could clog pipes.
Copper sulphate also has antibacterial and antifungal properties and is used to reduce harmful microorganisms that could affect water quality.
Copper sulphate is used as a catalyst in some polymerisation processes in the plastics and polymer industry, particularly in the production of special polymers. In plastics intended for marine use, copper sulphate is integrated into so-called antifouling coatings to prevent the growth of organisms such as algae and mussels.
Plastics used in medical or hygienic applications are enriched with copper sulphate to achieve antimicrobial properties. It inhibits the growth of bacteria, fungi and other micro-organisms on the surface.
Copper sulphate is used in combination with other chemicals as a flame retardant for polymers. It is also used as a starting material in the manufacture of colour pigments, which are required in the production of plastics. The substance can also be used as a component of additives to prevent polymer degradation caused by UV light. It improves the longevity and durability of plastics that are exposed to extreme environmental conditions.
Copper sulphate is used in the rubber and caoutchouc industry to prevent the microbial decomposition of natural rubber components, especially in humid environments. In latex processing, copper sulphate is used as an additive to support coagulation (solidification). In vulcanisation, it is used as a component of chemical accelerators or catalysts to improve the cross-linking of rubber molecules. This results in a more stable, elastic and durable end product.
Copper sulphate is also used to prepare the surfaces of rubber and caoutchouc parts for better adhesion with adhesives or other materials. It serves as a mordant that chemically activates the surface and enables improved bonding.
Copper sulphate is also used in the rubber industry as a raw material for the production of certain pigments used in the colouring of rubber products.
Copper sulphate is required in mining for the flotation of minerals. Among other things, it is used in froth flotation, one of the most common separation processes for extracting metals from ores. It is used as an activator in the separation of sulphide minerals, particularly in the flotation of zinc and lead sulphides.
Copper sulphate is a versatile reagent in analytical chemistry that plays a central role in many detection and analysis methods due to its colour formation, redox reactions and complex formation.
For example, it acts as a detection agent for water (moisture determination), reducing sugar (Fehling test) and proteins (Biuret test) as well as a standard solution that serves as a reference in quantitative analyses.

Further areas of application for copper sulphate

Copper sulphate is used as an electrolyte in electroplating, particularly in the copper plating process.
It is a versatile starting substance for the synthesis of numerous copper compounds (e.g. copper oxide, copper hydroxide, copper chloride, copper carbonate, copper acetate and copper nitrate), which are used in industry, research and everyday life. Due to its solubility in water, its ability to provide copper ions, its high reactivity and its easy handling, it is used in many chemical processes.