Copper(II) sulfate, the chemical compound with the formula CuSO4. Copper sulphate, blue stone, blue vitriol are all common names for penta hydrated cupric sulphate, CuS04.5H20, which is the best known and the most widely used of the copper salts. Indeed it is often the starting raw material for the production of many of the other copper salts. Today the world's consumption is around 250,000 tons per annum of which it is estimated that approximately three-quarters are used in agriculture, principally as a fungicide.
We produce high quality copper sulphate with low heavy metal content in our factory in Romania via SC Cuprichem SRL in Zlatna Park Industial, Alba Iulia. Our copper sulphate is suitable for animal feed and agricultural use since lead content is around 50 ppm, cadmium and arsenic contents are lover than 5 ppm. Technical grade copper sulphate is also available with low impurities. In our process no copper ore uses as raw material but only copper scrap from electrical cables with 99.99% copper.
Manufacture in the production of copper sulphate virgin copper is seldom, if ever, used as the starting raw material. Copper ores are used in countries where these are mined. For the bulk of the world's production nonferrous scrap is the general source. The scrap is refined and the molten metal poured into water to produce roughly spherical porous pieces about the size of marbles which are termed "shot". This shot is dissolved in dilute sulphuric acid in the presence of air to produce a hot saturated liquor which, if the traditional large crystals of copper sulphate are required, is allowed to cool slowly in large cooling vats into which strips of lead are hung to provide a surface for the crystals to grow on. If the granulated (snow) crystal grades are desired, the cooling process is accelerated by agitating the liquor in water cooled vessels.
Copper sulphate is a very versatile chemical with as extensive a range of uses in industry. It is also used as an algaecide, an herbicide in irrigation and municipal water treatment systems, and as a molluscicide, a material used to repel and kill slugs and snails. It is available in the following formulations: dusts, wettable powders, and fluid concentrates. Up to a generation or so ago about its only uses in industry were as a mordant for dyeing and for electroplating, but today it is being employed in many industrial processes. The synthetic fibre industry has found an application for it in the production of their raw material. The metal industry uses large quantities of copper sulphate as an electrolyte in copper refining, for copper coating steel wire prior to wire drawing and in various copper plating processes. The mining industry employs it as an activator in the concentration by froth flotation of lead, zinc, cobalt and gold ores. The printing trade takes it as an electrolyte in the production of electrotype and as an etching agent for process engraving. The paint industry uses it in anti-fouling paints and it plays a part in the colouring of glass. Indeed, today there is hardly an industry which does not have some small use for copper sulphate.
Copper sulphate has many agricultural uses but the following are the more important ones:
- Preparation of Bordeaux and Burgundy mixtures on the farm
- Control of fungus diseases
- Correction of copper deficiency in soils
- Correction of copper deficiency in animals
- Stimulation of growth for fattening pigs and broiler chickens
- A molluscicide for the destruction of slugs and snails, particularly the snail host of the liver fluke
Copper sulphate is a fungicide used to control bacterial and fungal diseases of fruit, vegetable, nut and field crops. Some of the diseases that are controlled by this fungicide include mildew, leaf spots, blights and apple scab. It is used in combination with lime and water as a protective fungicide, referred to as Bordeaux mixture, for leaf application and seed treatment.
Dissolving Copper Sulphate
Iron or galvanised vessels must not be used for the preparation of copper sulphate solutions. Copper sulphate dissolves in cold water to the extent of about 3 kg per 10 litres.
Preparation of Bordeaux Mixture
Bordeaux mixture is prepared in various strengths from copper sulphate, hydrated lime (calcium hydroxide) and water. The conventional method of describing its composition is to give the weight of copper sulphate, the weight of hydrated lime and the volume of water in that order. The percentage of the weight of copper sulphate to the weight of water employed determines the concentration of the Bordeaux mixture. Thus a 1% Bordeaux mixture, which is the normal, would have the formula 1 :1:100the first 1 representing 1 kg copper sulphate, the second representing 1 kg hydrated lime, and the 100 representing 100 litres (100 kg) water. As copper sulphate contains 25% copper metal, the copper content of a 1% Bordeaux mixture would be 0-25 % copper. The quantity of lime used can be reduced considerably. Actually 1 kg copper sulphate requires only 0.225 kg of chemically pure hydrated lime to precipitate all the copper. Good proprietary brands of hydrated lime are now freely available but, as even these deteriorate on storage, it is safest not to exceed a ratio of 2:1. i.e. a 1:0.5:100 mixture.
In preparing Bordeaux mixture, the copper sulphate is dissolved in half the required amount of water in a wooden or plastic vessel. The hydrated lime is mixed with the balance of the water in another vessel. The two "solutions" are then poured together through a strainer into a third vessel or spray tank.
Preparation of a 1% Burgundy Mixture
Dissolve separately 1 kg copper sulphate in 50 litres water and 125 kg washing soda (or 0.475 kg soda ash) in 50 litres water and slowly add the soda solution to the copper sulphate solution with stirring. Control of fungus diseases
Bordeaux and Burgundy mixtures have been found effective in controlling a whole host of fungus diseases of plants. Normally a 0.5 % to 1 % Bordeaux or Burgundy mixture applied at 2 to 3 week intervals suffices to control most copper-susceptible fungi.
Generally once the fungus spores have alighted on the host plant and penetrated the tissues it is difficult to control them. The principle of control must in most cases depend on protection, ie preventing the fungus spores from entering the host tissues. Copper fungicides are noted for their tenacity and for this reason are much to be preferred in areas of high rainfall.
The simplest method of control is to apply a protective coating of Bordeaux or Burgundy mixture (or other copper fungicide) to the susceptible parts of the plant, so that spores alighting on them come in contact with the protective film of copper and are killed instantly. It is thus important to remember that the first spraying must ideally be made just before the disease is expected and continued at intervals throughout the susceptible period. For this reason it is important to take advantage of the early warning schemes which are in operation to ensure greater accuracy of the timing of the first spraying.
It must also be remembered that fungi are plants and that control measures that will kill them may not always leave the host plant unaffected. The use of too concentrated a fungicide mixture must therefore be guarded against, particularly for the early sprays.
Copper fungicides have been reported effective against numerous plant diseases. A list, by no means exhaustive, of some 300 diseases that have been found amenable to control by copper fungicides, appears in Table B.
Correction of Copper Deficiency in Soils
Where copper deficiency has been confirmed by soil analysis or field diagnosis, whether in plants or animals, it can be corrected very simply either by applying 50 kg copper sulphate per hectare in the form of a fertiliser before sowing or by spraying the foliage of the young cereal plants, when they are about 150 mm high, with 750 grams copper sulphate (dissolved in from 400 to 2,000 litres water) per hectare. The soil application has generally given the better results and has the advantage that it may have a residual effect for more than ten years. The foliar application has to be given annually to each crop. An alternative is to add a copper containing slag (normally about 1% to 2 % copper) at a rate of a tonne to the hectare.
We produce copper sulphate technical grade, agricultural grade, and free flowing copper sulphate, all with extremely low heavy metal content.
Customer satisfaction is our main target. Our sales and support teams are working only to provide your needs on time.