PRODUCTS

CUPRIC HYDRATE

Cupric hydrate is used as a source for Copper salts and as a mordant in dyeing textiles.
Cupric hydrate in ammonia solution, known as Schweizer's reagent, possesses the interesting ability to dissolve cellulose, which led to its use in the production of rayon.
Cupric hydrate is used widely in the aquarium industry for its ability to destroy external parasites in fish without killing the fish.

CAS Number: 20427-59-2
EC Number: 243-815-9
Chemical Formula: Cu(OH)2
Molar Mass: 97.561 g/mol

Synonyms: 20427-59-2, Copper(II) hydroxide, Copper dihydroxide, copper;dihydrate, copper(II)hydroxide, dihydroxycopper, MFCD00010968, Kuprablau, Parasol, Champ, Cuzin, Kocide, Wetcol, Cupravit blau, Comac Parasol, Cupravit Blue, Blue Shield, Technical Hydrox, Funguran OH, KOP Hydroxide, Blue Shield DF, Kocide DF, Kocide LF, Kocide SD, Champ Formula II, Nu-Cop, KOP Hydroxide WP, Spin Out FP, Kocide 101, Kocide 101PM, Kocide 220, Kocide 404, Caswell No. 242, Copper(2+) hydroxide, Kocide 2000, copper hydrate, Copper hydroxide (Cu(OH)2), HSDB 262, Hydrocop T, EINECS 243-815-9, EPA Pesticide Chemical Code 023401, Kocide Cupric Hydroxide Formulation Grade, Kocide Copper Hydroxide Antifouling Pigment, Cu(OH)2, Cupric Hydroxide Formulation Grade Agricultural Fungicide, DTXSID6034473, AKOS015903383, Copper(II) hydroxide, technical grade, EC 243-815-9, Copper hydroxide, Cuprichydroxide, copper;dihydroxide, 1344-69-0, COPPER(I)HYDROXIDE, 12125-21-2, Cuprous hydroxide, Copper monohydroxide, Copper(I) hydroxide, Spinout, PEI 24, EINECS 215-705-0, CuO2, CHEBI:81907, AKOS030228342, S521, C18712, Q186357, J-013306, J-520119, Copper(II) carbonate hydroxide, 12069-69-1, Carbonate hydroxyde de cuivre(2+) , Carbonic acid, copper(2+) salt, hydrate , Copper carbonate hydroxide, copper carbonate, basic , Copper hydroxide carbonate, Copper(2+)ato(2-) carbonatato(2-) hydroxido(2-), Cupric carbonate hydroxide, Kupfer(2+)carbonathydroxid , Kupfer(2+)carbonathydroxid, (Carbonato(2-))dihydroxydicopper, (Carbonato)dihydroxydicopper, 1344-66-7 , 138210-92-1 , 235-113-6 , 37396-60-4 , 39361-73-4 , BASIC COPPER CARBONATE, Basic copper(II) carbonate, Basic cupric carbonate, Carbonic acid, copper(2+) salt , Copper hydroxide carbonate (CuCO3.Cu(OH)2), Copper hydroxy carbonate, Copper hydroxy carbonate (Cu2(OH)2CO3), Copper(II) carbonate basic, Copper(II) carbonate copper(II) hydroxide , Copper(II) carbonate dihydroxide, Copper(II) carbonate hydroxide , Copper(II) carbonate, basic, Copper(II) hydroxide carbonate, Copper, (carbonato)dihydroxydi-, Copper, (μ-(carbonato(2-)-O:O'))dihydroxydi-, Copper, (μ-(carbonato(2-)-κO:κO'))dihydroxydi-, Cupric carbonate basic, Cupric carbonate hydroxide (CuCO3.Cu(OH)2), Cupric carbonate, basic, Cupric subcarbonate, dicopper carbonate dihydroxide, Dicopper dihydroxycarbonate, dicupric carbonate dihydroxide, Kop karb

Cupric hydrate is also called cupric hydroxide is a pale blue precipitate produced when sodium or potassium hydroxide is added in excess to a solution of a copper salt.
Cupric hydrate is crystalline but inert compound used in the preparation of a wide variety of salts.
Cupric hydrate is prepared by adding just sufficient aqueous ammonia to cupric sulphate to hold the copper in solution and then precipitating the hydroxide either by the addition of an equivalent quantity of alkali by removing ammonia from the solution using a dessicator.

Cupric hydrate is a highly water insoluble crystalline Copper source for uses compatible with higher (basic) pH environments.
Hydroxide, the OH- anion composed of an oxygen atom bonded to a hydrogen atom, is commonly present in nature and is one of the most widely studied molecules in physical chemistry.

Hydroxide compounds have diverse properties and uses, from base catalysis to detection of carbon dioxide.
In a watershed 2013 experiment, scientists at JILA (the Joint Institute for Laboratory Astrophysics) achieved evaporative cooling of compounds for the first time using hydroxide molecules, a discovery that may lead to new methods of controlling chemical reactions and could impact a range of disciplines, including atmospheric science and energy production technologies.

Cupric hydrate is generally immediately available in most volumes.
Ultra high purity and high purity compositions improve both optical quality and usefulness as scientific standards.
Nanoscale elemental powders and suspensions, as alternative high surface area forms, may be considered.

The orthorhombic nature of Cupric hydrate crystals was determined by X ray diffraction.
Cupric hydrate can act as a heterogeneous catalyst in the selective oxidative cross coupling of terminal alkynes to yield their corresponding ynamides.

A bright blue-green gel or light blue powder.
Cupric hydroxide will decompose with time or heat to form black copper oxide.

Cupric hydrate is used as a source for Copper salts and as a mordant in dyeing textiles.
Cupric hydrate reacts with Ammonium hydroxide to form the cuprammonium ion that is capable of dissolving Cellulose.

Cupric hydrate is used in the manufacture of rayon.
Cupric hydrate has also been reported as a component in marine corrosion crusts on copper alloys.

Cupric hydrate is the hydroxide of copper with the chemical formula of Cu(OH)2.
Cupric hydrate is a pale greenish blue or bluish green solid.

Some forms of Cupric hydrate are sold as "stabilized" Cupric hydrate, although they likely consist of a mixture of copper(II) carbonate and hydroxide.
Cupric hydroxide is a strong base, although Cupric hydrates low solubility in water makes this hard to observe directly.

Cupric hydrate (chemical formula Cu(OH)2) is the hydroxide of the metal copper.
The typical color of Cupric hydrate is blue.

Some forms of Cupric hydrate are sold as "stabilized" Cupric hydrate, quite likely a mixture of copper(II) carbonate and hydroxide.
These are often greener in color.

Coppers, fixed – Cupric hydrate, copper oxide, copper oxychloride, includes products exempted from EPA tolerance, provided, that, copper-based materials must be used in a manner that minimizes accumulation in the soil and shall not be used as herbicides.

Cupric hydrate is the hydroxide of the metal copper with the chemical formula of CuOH.
Cupric hydrate is a mild, highly unstable alkali.

The color of pure Cupric hydrate is yellow or orange-yellow, but Cupric hydrate usually appears rather dark red because of impurities.
Cupric hydrate is extremely easily oxidized even at room temperature.

Cupric hydrate is useful for some industrial processes and in preventing condensation of formaldehyde.
Cupric hydrate is also an important reactant and intermediate for several important products including Cu2O3 and Cu(OH)2.

Additionally, Cupric hydrate can act as a catalyst in the synthesis pyrimidopyrrolidone derivatives.
Cupric hydrate used as fungicides.

A mixture of Cupric hydrate and copper sulfate is also used as insecticides and pesticides.
Malachite Cupric hydrate is a bright green mineral used as a semiprecious stone for making ornaments.

Cupric hydrate is formed by adding a sodium hydroxide to a dilute solution of copper(II) sulfate(CuSO4·5H2O).

Cupric hydrate is an ionic compound.
Cupric hydrate undergoes dissociation to produce Cu2+ cation and OH- anion.
Cu is a metal and oxygen is non-metal so the bond between Cu and Oxygen is ionic in nature.

Cupric hydrate is a hydrated copper oxide, and Cupric hydrate does provide some concentration of OH- ions when Cupric hydrate is in the presence of acids (H3O+).
However, Cupric hydrate is largely insoluble in water.
Therefore, Cupric hydrate would not be considered an alkali, but rather a weak base.

Cupric hydrate used as a fungicide.
Cupric hydrate which is used to kill parasitic fungi or their spores is known as fungicide.

Cupric hydrate is a quite inexpensive and abundant material, but the literature contains no reports of using Cupric hydrate as a stable water oxidation catalyst (WOC).
In this study, we report for the first time that Cu(OH)2 material synthesized from a simple copper salt can be used as a WOC with good activity and stability.
Under optimal conditions using Cu(OH)2 as the electrocatalyst, a catalytic current density of 0.1 mA/cm2 can be achieved under an applied potential of ∼1.05 V relative to Ag/AgCl at pH 9.2.

The slope of the Tafel plot is 78 mV/dec.
The Tafel plot indicates that a current density of ∼0.1 mA/cm2 requires an overpotential of 550 mV.

The Faradaic efficiency was measured to be ∼95%.
The as-synthesized Cu(OH)2 material was characterized by X-ray powder diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy.

Cupric hydrate is used as a fungicide for agriculture, as a mordant, as a source for copper salts, and for the manufacturing of rayon.

Applications of Cupric Hydrate:
Cupric hydrate based monoliths can be used in the synthesis of Cupric hydrate-based monolithic xerogels.
Potential applications of this metal organic frameworks (MOFs) include gas storage, separation, drug delivery, and biomedicine.
Supported Cu(OH)x can be used as a catalyst for the aerobic cross dehydrogenative coupling of benzenethiols and cyclic amides to yield N-acylsulfenamides.

Cupric hydrate is an important intermediate in the formation of copper(I) oxide (Cu2O).
The Cu2O compound has versatile applications such as for use in solar cells, for the oxidation of fiberglass, and for use in lithium ion batteries.

Cupric hydrate has even been shown to have a useful application in the development of DNA biosensors for the hepatitis B virus.
Notably, Cupric hydrate has been found that both CuOH and Cu(OH)2 must be simultaneously present for the synthesis of Cu2O.

Uses of Cupric Hydrate:
Cupric hydrate fungicides, first developed in the 1970’s, have become favored for most fungicide applications.
A mixture of Cupric hydrate and copper sulfate is used as insecticides and pesticides.

Malachite Cupric hydrate carbonate a bright green mineral used as an ore of copper and as a semiprecious stone for making ornaments.
Cupric hydrate has been used as an effective biocides as wood preservatives.

Cupric hydrate in ammonia solution, known as Schweizer's reagent, possesses the interesting ability to dissolve cellulose.
This property led to Cupric hydrate being used in the production of rayon, a cellulose fiber.

Cupric hydrate is also used widely in the aquarium industry for Cupric hydrates ability to destroy external parasites in fish, including flukes, marine ich, Brooklynellosis, and marine velvet, without killing the fish.
Although other water-soluble copper compounds can be effective in this role, they generally result in high fish mortality.

Cupric hydrate has been used as an alternative to the Bordeaux mixture, a fungicide and nematicide.
Cupric hydrate is also occasionally used as ceramic colorant.

Cupric hydrate has been combined with latex paint, making a product designed to control root growth in potted plants.
Secondary and lateral roots thrive and expand, resulting in a dense and healthy root system.

Cupric hydrate was sold under the name Spin Out, which was first introduced by Griffin L.L.C.
Cupric hydrate is now sold as Microkote either in a solution you apply yourself, or as treated pots.

Cupric hydrate has been used as an alternative to the Bordeaux mixture, a fungicide and nematacide.
Nowadays, Cupric hydrate is disfavored because of environmental contamination problems.
Cupric hydrate is also occasionally used as ceramic colorant.

Industry Uses:
Agricultural chemicals (non-pesticidal)
Architectural and electrical products
Industrial Use
Intermediates
Metal Recovery
Metals recovery
Solids separation agents
Used as a smelter feedstock for metal recovery
Used as smelter feedstock for metal recovery
used as smelter feedstock for metal recovery

Use as an organic reagent:
Cupric hydrate has a rather specialized role in organic synthesis.
Often, when Cupric hydrate is utilized for this purpose, Cupric hydrate is prepared in situ by mixing a soluble copper(II) salt and potassium hydroxide.

Cupric hydrate is sometimes used in the synthesis of aryl amines.
For example, Cupric hydrate catalyzes the reaction of ethylenediamine with 1-bromoanthraquinone or 1-amino-4-bromoanthraquinone to form 1-((2-aminoethyl)amino)anthraquinone or 1-amino-4-((2-aminoethyl)amino)anthraquinone, respectively.

Cupric hydrate also converts acid hydrazides to carboxylic acids at room temperature.
This is especially useful in synthesizing carboxylic acids with other fragile functional groups.
The published yields are generally excellent as is the case with the production of benzoic acid and octanoic acid.

Structure of Cupric Hydrate:
The structure of Cupric hydrate has been determined by X-ray crystallography The copper center is square pyramidal.
Four Cu-O distances in the plane range are 1.96 Å, and the axial Cu-O distance is 2.36 Å.

The hydroxide ligands in the plane are either doubly bridging or triply bridging.
Cupric hydrate can be a linear molecule of the symmetry group C∞v.

For the linear structure, the bond distance of the Cu-O bond has been found to be 1.788 Å and the distance of the O-H bond has been found to be 0.952 Å.
The Cupric hydrate bond angle was measured as 180°.

There is also the possibility of a formed Cupric hydrate with the point group Cs.
This has been found to have increased stability compared to the linear geometry.

In this case, the bond distance of the Cu-O bond was 1.818 Å and the bond distance of the O-H bond was 0.960 Å.
The bond angle for this geometry was 131.9°.
Cupric hydrate is highly ionic in character, which is why this angle is not exactly 120°.

Spectroscopic characterization of Cupric Hydrate:
Cupric hydrate has been characterized spectroscopically using intracavity laser spectroscopy, single vibronic level emission, and microwave spectroscopic detection.

Reagent for organic chemistry of Cupric Hydrate:
Cupric hydrate has a rather specialized role in organic synthesis.
Often, when Cupric hydrate is utilized for this purpose, Cupric hydrate is prepared in situ by mixing a soluble copper(II) salt and potassium hydroxide.

Cupric hydrate also converts acid hydrazides to carboxylic acids at room temperature.
This conversion is useful in the synthesis of carboxylic acids in the presence of other fragile functional groups.
The yields are generally excellent as is the case with the production of benzoic acid and octanoic acid.

Copper (I) vs other oxidation states of Cupric Hydrate:
Cu+ and Cu2+ are the most common oxidation states of copper although Cu3+ and Cu4+ have also been reported.

Cu2+ tends to form stable compounds whereas Cu+ usually forms unstable compounds such as Cupric hydrate.
One exception to this is Cu2O, which is much more stable.

However, aside from Cupric hydrate, compounds containing Cu+ have not been studied as extensively as Cu2+ compounds due to their relative instability.
This includes Cupric hydrate.

Reactions of Cupric Hydrate:
Moist samples of Cupric hydrate slowly turn black due to the formation of copper(II) oxide.
When Cupric hydrate is dry, however, Cupric hydrate does not decompose unless Cupric hydrate is heated to 185°C.

Cupric hydrate reacts with a solution of ammonia to form a deep blue solution consisting of the [Cu(NH3)4]2+ complex ion, but the hydroxide is reformed when the solution is diluted with water.
Cupric hydrate in ammonia solution, known as Schweizer's reagent, possesses the interesting ability to dissolve cellulose.
This property led to Cupric hydrate being used in the production of rayon, a cellulosic fiber.

Since Cupric hydrate is mildly amphoteric, Cupric hydrate dissolves slightly in concentrated alkali, forming [Cu(OH)4]2-.

Similar to iron(II) hydroxide, Cupric hydrate can easily oxidise into Cupric hydrate:
4CuOH + 2H2O + O2 <=> 4Cu(OH)2

Production of Cupric Hydrate:

Cupric hydrate can be produced by adding sodium hydroxide to a solution of a soluble copper(II) salt, such as copper(II) sulfate (CuSO4·5H2O):
2NaOH + CuSO4·5H2O → Cu(OH)2 + 6H2O + Na2SO4

The precipitate produced in this manner, however, often contains water and an appreciable amount of sodium containing impurities.
A purer product can be attained if ammonium chloride is added to the solution beforehand.

Alternatively, Cupric hydrate is readily made by electrolysis of water (containing a little electrolyte such as sodium sulfate or magnesium sulfate) with a copper anode:
Cu + 2OH− → Cu(OH)2 + 2e−

Producing Process of Cupric Hydrate:
Cupric hydrate is produced by a reaction of copper oxychloride in an aqueous suspension with alkali hydroxide or alkaline earth metal hydroxide in the presence of a stabilizing agent and the product is separated and washed.
To improve the stability of the Cupric hydrate and to avoid a black coloring by copper oxide, inorganic silicon compounds which contain hydroxyl groups (SiOH) in the molecules or form such groups in an aqueous medium are added to the suspension.
Cupric hydrate is desirable to use particulate solid silicic acids or silicic acids which are soluble in water or colloidally dissolved.

Cupric hydrate (as the rarely occurring mineral spertiniite) is formed under alkaline, oxidising conditions.
Cupric hydrate has been observed as a naturally occurring corrosion product of brass in sea water.

But most occurrences on copper alloys are due to conservation treatments using basic solutions (sodium hydroxide or ammonia) or to intentional patination.
Classical brass centrepieces (c. 1800), ‘cleaned’ with ammonia solution, developed a blue spertiniite patina in gaps, where evaporation was hindered.

Additional to the danger of stress corrosion cracking this is another reason now outlawing this treatment.
Copper pigment layers will transform to Cupric hydrate when exposed to bases.

The treatment of basic copper salts with bases has been used intentionally in the production of Bremen blue and similar pigments which can be composed of Cupric hydrate as well.
When concentrated ammonia solution (ammonium hydroxide) is added to a clear, light blue, aqueous solution of copper(II) chloride, a powdery, light blue precipitate of Cupric hydrate forms.

Further addition of ammonia causes the copper ion to go back into solution as a deep blue ammonia complex.
The addition of 12M sulfuric acid reverses the changes through the Cupric hydrate precipate back to clear, light blue color of the original solution.

This is less reactive than copper carbonate basic and more reactive than cupric oxide (CuO).
This material does not contribute to CO2 bubbling in glazes.

Cupric hydrate has a fairly complex decomposition as Cupric hydrate is heated to melting point.
Around 185C Cupric hydrate loses about 18% weight as Cupric hydrate decomposes to the heat stable CuO (cupric oxide) which remains stable until 1000C.
Around 1050C about 6.5% is lost, likely involving partial loss of oxygen to form a mix of cuprous and cupric oxides.

Please check the accompanying curve to see the history of weight loss as this is fired.
You can see how much weight Cupric hydrate lost, where Cupric hydrate occurs and how fast Cupric hydrate happens.
Compare this with Copper Carbonate Basic to see the difference.

Cupric hydrate is the hydroxide of copper with the chemical formula of Cu(OH)2.
Cupric hydrate is a pale greenish blue or bluish green solid.

Field of the invention:
Our present invention relates to a process of producing stabilized Cupric hydrate i.e. Cupric hydrate from copper oxychloride by a reaction with basic substances.

Background of the invention:
The process of producing Cupric hydrate from copper oxychloride known uses phosphate ions to ensure that the product will be stable and storable.
These phosphate ions are added before the copper oxychloride suspended in an aqueous phase is reacted with alkali metal hydroxide and/or alkaline earth metal hydroxide, the precipitated Cupric hydrate formed by the reaction is washed and the resuspended Cupric hydrate is stabilized by a treatment with acid phosphate with an adjustment of a pH value between 7.5 and 9.

That process consists of a plurality of steps, at high labor and equipment cost.
For this reason Cupric hydrate is also known to produce Cupric hydrate without a subsequent pH adjustment.
This process has the disadvantage that the Cupric hydrate product is converted at least in part to black copper(II) oxide during prolonged storage or earlier during a drying treatment.

Objects of the invention:
Cupric hydrate is the general object of our invention to provide a method of making stable Cupric hydrate which obviates the disadvantages of the prior art processes.
Cupric hydrate is another object of the invention to provide for the production of Cupric hydrate from copper oxychloride a process which involves only low labor and equipment costs so that Cupric hydrate can be carried out in a simple manner and which results in a stable, storable Cupric hydrate.

Description of the invention:
Cupric hydrate is produced by a reaction of hydroxide or alkaline earth metal hydroxide in the presence of a stabilizing agent separating and washing the product.
In accordance with the invention in the stabilizing agent consists of one or more inorganic silicon compounds which contain hydroxyl groups (SiOH, silanol groups) in the molecule or form such groups in an aqueous medium and is added an amount of 1 to 10% by weight of the solid Cupric hydrate.

By the addition of one or more of these substances in accordance with the invention a stabilization of the precipitated Cupric hydrate is effected in a simple manner and even a partial conversion of the Cupric hydrate to black copper(II) oxide will be avoided during a prolonged storage as a suspension and during recovery of dry Cupric hydrate.
Within the scope of the invention, suitable stabilizing agents include particulate solid silicic acids or silicic acids which are dissolved or colloidally dispersed in a aqueous medium.

Those additives which are insoluble in water are directly added to the aqueous suspension of a freshly prepared copper oxychloride.
In that case the additives are added to the copper oxychloride suspension in the reaction vessel immediately before the reaction with alkali metal hydroxide or alkaline earth metal hydroxide.

Stabilizing agents which are soluble in water or colloidally dispersible therein are suitably added to a separately prepared Cupric hydrate suspension immediately after the washing and filtering process.
Suitable water-insoluble inorganic silicon compounds which contain hydroxyl groups in the molecule or form such groups in an aqueous medium include pyrogenic silicic acids, such as silicic acids formed by a thermal decomposition of silicon tetrachloride in an oxyhydrogen gas flame.

Such pyrogenic silicic acids generally have a particle diameter between 10 and 20 millimicrons and will improve also the physical properties of the final product, for instance, the aqueous suspensibility or wettability of the Cupric hydrate.
Particulate silica can similarly be used.

A properly classified silica having a particle size between 10 and 80 millimicrons is preferred in that case.
In an aqueous medium, the solid silicic acids tend to take up water molecules by an addition reaction with formation of hydrogen-bond bridges so that a large proportion of SiOH groups is formed.

Substances which may be used to form a stabilized Cupric hydrate in the process in accordance with the invention include also the silicic acids which are soluble in water or colloidally dissolved, such as the orthosilicic acid, metasilicic acid or polysilicic acids.
Suitable stabilizing agents include, e.g., silica sols or silica gels made from water-glass solutions by an addition of dilute acids.
In a preferred embodiment of the invention, dissolved alkali metal silicate may be used, e.g., in the form of a water-glass solution.

As noted, in the process in accordance with the invention the inorganic silicon compounds are used in an amount equal to 1 to 10% by weight of the solid Cupric hydrate.
In a preferred embodiment of the invention a stabilized Cupric hydrate is produced in a process in which the stabilizing agent is used in an amount of 2 to 5% of the solid Cupric hydrate.

In another desirable embodiment of the invention, a stabilizer is selected which will also improve important physical properties of the final product, such as Cupric hydrates water suspensibility and wettability, which properties are required for various uses, particularly in agriculture for the protection of crops with copper-containing agents.
Pyrogenic silicic acids are particularly suitable for that purpose.

In the process in accordance with the invention Cupric hydrate is also necessary to take care and to ensure that the suspension of the stabilized Cupric hydrate has a pH value in the range from 7.5 to 9.
This is accomplished in a simple manner by washing or by addition of phosphoric acid.

The process in accordance with the invention has numerous advantages.
For instance the washing water which becomes available in the process in accordance with the invention contains virtually no substances which pollute the effluent.

The mother liquor and part of the spent washing water which becomes available can be recycled and re-used to suspend the copper oxychloride employed as a starting product, although the concentration of the alkaline solution must be increased in that case from an initial value of 2 to 5 grams per liter to 4 to 10 grams per liter.
The stabilized Cupric hydrate produced by the process in accordance with the invention contains 45 to 61 wt.% copper.

Cupric hydrate has a particle size of 0.1 to 5 microns and Cupric hydrates physical and chemical composition will not change even with storage over several years.
The Cupric hydrate produced by the process in accordance with the invention is particularly suitable for making other copper compounds, for the further processing to copper-based coloring materials and for the production of preparations for the protection of crops.

Specific examples:
The invention will be explained more in detail by the following Examples.

Example 1:
116 liters of a freshly prepared suspension of copper oxychloride having a solids content of 860 grams per liter are mixed with stirring with 3 kg pyrogenic silicic acid finely dispersed in 600 liters water.
A solution of 36 kg caustic soda in 150 liters water was subsequently quickly admixed, while a reaction temperature of up to 25° C was maintained.

The reaction was completed after a few minutes; this was apparent from an intense blue color of the resulting Cupric hydrate.
The resulting Cupric hydrate was subsequently washed with water on a rotary filter.

This resulted in a decrease of the pH value to 7.5 to 9.
The product obtained could be processed further as a suspension or after having been dried to a powder.
No formation of copper(II) oxide with development of a black color has noted during the storage of the liquid product or during the drying of the product.

Example 2:
The process of Example 1 was repeated but the water employed as a suspension medium for the copper oxychloride used as a starting product was replaced by the mother liquor enriched with caustic soda solution and by part of the spent washing water.
The sodium chloride contained in that water had an influence only in that the concentration of the alkaline solution had to be increased from 4 g/l in Example 1 to 7 g/l.

Claims:
A method of producing Cupric hydrate which comprises reacting copper oxychloride in an aqueous suspension with a substance selected from the group consisting of alkali hydroxide and alkaline earth metal hydroxide, adding as a stabilizer agent for the Cupric hydrate at least one inorganic silicon compound selected from the group consisting of silicon compounds containing hydroxyl groups in their molecules and silicon compounds forming hydroxyl groups in an aqueous medium, in a quantity of 1 to 10% by weight of the solid Cupric hydrate formed; and recovering and washing the said Cupric hydrate thus formed.
The method defined in claim 1 wherein said silicon compound is a compound selected from the group which consists of particulate solid silicic acid, water-soluble silicic acid, and colloidally dissolved silicic acid.

The method defined in claim 2 wherein said silicon compound is selected from the group which consists of orthosilicic acid, metasilicic acid or polysilicic acid.
The method defined in claim 1 wherein said compound is particulate pyrogenic silicic acid produced by a decomposition of silicon tetrachloride.

The method defined in claim 1 wherein said compound is a particulate silica having a particle size of 10 to 80 millimicrons.
The method defined in claim 1 wherein said compound is an alkali metal silicate.
The method defined in claim 1 wherein said inorganic silicon compound is used in an amount of 2 to 5% by weight of the solid Cupric hydrate.

Preparation of Cupric Hydrate:
Cupric hydrate can be made by adding very dilute sodium hydroxide to a soluble copper(II) salt, and not the other way around.
The hydroxide precipitates, with the best samples precipitating in colder solutions.
In excessively basic conditions, the hydroxide formed will rapidly convert to copper(II) oxide, which is exacerbated by heating.

If aqueous ammonia is used instead of sodium hydroxide, the Cupric hydrate precipitated has much greater air stability, but if excess ammonia is added, the hydroxide will begin to dissolve, forming the deep blue tetraammine copper(II) complex.
A diluted solution of sodium hydroxide is then added to precipitate the Cupric hydrate from the solution, and this route has the advantage of preventing local hotspots which cause the formation of copper(II) oxide.

Very pure Cupric hydrate can also be made via electrolysis of water with a copper anode, containing small amounts of sodium sulfate.

The dissociation of Cu(OH)2- leads to the formation of Cupric hydrate.
Cu(OH)2- <=> CuOH + OH-

The dissociation energy required for this reaction is 62 ± 3 kcal/mol.

Another method is by the double displacement of CuCl and NaOH：
CuCl + NaOH <=> NaCl + CuOH

Notably, this method is rarely used because the Cupric hydrate produced will gradually dehydrate and eventually turn into Cu2O.

General Manufacturing Information of Cupric Hydrate:

Industry Processing Sectors:
Agriculture, forestry, fishing and hunting
All other basic inorganic chemical manufacturing
Computer and electronic product manufacturing
Mining (except oil and gas) and support activities
Other - Secondary Precious Metals Reclaimers
Primary metal manufacturing

Synthesis of Cupric Hydrate:
Cupric hydrate can be produced by adding a small amount of sodium hydroxide to a dilute solution of copper(II) sulfate (CuSO4 · 5H2O).
The precipitate produced in this manner, however, often contains an appreciable amount of sodium hydroxide impurity and a purer product can be attained if ammonium chloride is added to the solution beforehand.

Alternatively, Cupric hydrate is readily made by electrolysis of water (containing a little electrolyte such as sodium bicarbonate).
A copper anode is used, often made from scrap copper.

"Copper in moist air slowly acquires a dull green coating. The green material is a 1:1 mole mixture of Cu(OH)2 and CuCO3."
2Cu(s) + H2O(g) + CO2(g) + O2(g) ---> Cu(OH)2(s) + CuCO3(s)

Catalytic activity of Cupric Hydrate:
Cupric hydrate can act as a catalyst.
Cupric hydrate has been found to be useful in the reaction of heterocyclic ketene aminals (an important building block) with diazoesters.

This reaction is used to synthesize pyrimidopyrrolidone derivatives with high yields and mild reaction conditions needed.
As a catalyst in these reactions, Cupric hydrate is used with potassium tert-butoxide and argon with tert-butyl hydroperoxide and dichloroethane.

25 examples of these reactions were successfully performed.
Chemicals in the pyrrolidone family have been useful for drug development, including pharmaceuticals for the neuroprotection after strokes and in anti-seizure medications.

Although these are psychoactive drugs, they tend to have fewer side effects than their counterparts.
The mechanisms by which these drugs work have yet to be established.

Cupric hydrate is stable to about 100 °C.
Cupric hydrate reacts with a solution of ammonia to form a deep blue solution of tetramminecopper [Cu(NH3)4]2+ complex ion.

Cupric hydrate catalyzes the oxidation of ammonia solutions in presence of dioxygen, giving rise to copper ammine nitrites, such as Cu(NO2)2(NH3)n.
Cupric hydrate is mildly amphoteric.
Cupric hydrate dissolves slightly in concentrated alkali, forming [Cu(OH)4]2−.

Other Cupric hydrates:
Together with other components, Cupric hydrates are numerous.
Several copper(II)-containing minerals contain hydroxide.
Notable examples include azurite, malachite, antlerite, and brochantite.
Azurite (2CuCO3·Cu(OH)2) and malachite (CuCO3·Cu(OH)2) are hydroxy-carbonates, whereas antlerite (CuSO4·2Cu(OH)2) and brochantite (CuSO4·3Cu(OH)2) are hydroxy-sulfates.

Many synthetic Cupric hydrate derivatives have been investigated.

Chemical Properties of Cupric Hydrate:
Cupric hydrate reacts with sulfuric acid forms copper sulfate and water.

The chemical equation is given below.
Cu(OH)2 + H2SO4 → CuSO4 + 2 H2O

Mineral of Cupric Hydrate:
The mineral of the formula Cu(OH)2 is called spertiniite.
Cupric hydrate is rarely found as an uncombined mineral because Cupric hydrate slowly reacts with carbon dioxide from the atmosphere to form a basic copper(II) carbonate.

Thus copper slowly acquires a dull green coating in moist air by the reaction:
2 Cu(OH)2 + CO2 → Cu2CO3(OH)2 + H2O

The green material is in principle a 1:1 mole mixture of Cu(OH)2 and CuCO3.
This patina forms on bronze and other copper alloy statues such as the Statue of Liberty.

Occurrence of Cupric Hydrate:
Cupric hydrate has been known since copper smelting began around 5000 BC although the alchemists were probably the first to manufacture Cupric hydrate by mixing solutions of lye (sodium or potassium hydroxide) and blue vitriol (copper(II) sulfate).
Sources of both compounds were available in antiquity.

Cupric hydrate was produced on an industrial scale during the 17th and 18th centuries for use in pigments such as blue verditer and Bremen green.
These pigments were used in ceramics and painting.

Natural occurrence:
Cupric hydrate is found in several different copper minerals, most notably azurite, malachite, antlerite, and brochantite.
Azurite (2CuCO3 • Cu(OH)2 ) and malachite (CuCO3 • Cu(OH)2) are carbonates while antlerite (CuSO4 • 2Cu(OH)2) and brochantite (CuSO4 • 3Cu(OH)2) are sulfates.
Cupric hydrate is rarely found as an uncombined mineral because Cupric hydrate slowly reacts with carbon dioxide from the atmosphere to form a basic copper(II) carbonate.

History of Cupric Hydrate:
Cupric hydrate has been known to man since copper smelting began around 5000 BCE although the alchemists were probably the first to manufacture Cupric hydrate.
This was easily done by mixing solutions of lye and blue vitriol, both chemicals which were known in antiquity.

Cupric hydrate was produced on an industrial scale during the 17th and 18th centuries for use in pigments such as blue verditer and Bremen green.
These pigments were used in ceramics and painting.

Pharmacology and Biochemistry of Cupric Hydrate:

Absorption, Distribution and Excretion:
Ionic copper is absorbed from the stomach, duodenum, & jejunum.
The initial absorption is about 30%, but the effective net absorption is only about 5% due to excretion of copper into the bile; biliary copper is bound to protein, & this complex is not reabsorbed.

Absorption is influenced by a number of factors including the chemical forms of copper: oxides, hydroxides, iodides, glutamates, citrates, & pyrophosphates of copper are readily absorbed, but copper sulfides & other water insoluble salts are poorly absorbed.
Copper complexes of some amino acids are easily absorbed, whereas copper porphyrins present in meat are very poorly absorbed.

Handling and storage of Cupric Hydrate:

Storage:
Dry Cupric hydrate should be stored in closed plastic bottles.

Advice on safe handling:
Work under hood.
Do not inhale substance/mixture.

Hygiene measures:
Change contaminated clothing.
Preventive skin protection recommended.

Wash hands after
working with substance.

Conditions for safe storage, including any incompatibilities:

Storage conditions:
Tightly closed.
Dry.

Keep in a well-ventilated place.
Keep locked up or in an area accessible only to qualified or authorized persons.

Keep in a dry place.
Air and moisture sensitive.

Store under argon.
Hygroscopic.
Store at controlled room temperature (15 to 30°C).

Storage class:
Storage class (TRGS 510): 6.1B: Non-combustible, acute toxic Cat. 1 and 2 / very toxic hazardous materials

Stability and reactivity of Cupric Hydrate:

Reactivity:
No data available

Chemical stability:
The product is chemically stable under standard ambient conditions (room temperature).

Possibility of hazardous reactions:

Violent reactions possible with:
Strong acids
Acid anhydrides

Conditions to avoid:
no information available

Incompatible materials:
No data available

Safety of Cupric Hydrate:
Cupric hydrate is mostly safe, but oral and skin exposure should be limited when wet, as Cupric hydrate is sparingly soluble, and the general trend among soluble copper compounds is that they act as irritants and are mildly toxic.
Dilute hydrochloric acid in the stomach may react with Cupric hydrate to form copper(II) chloride, which is more of a concern.

First aid measures of Cupric Hydrate:

General advice:
First aiders need to protect themselves.
Show this material safety data sheet to the doctor in attendance.

If inhaled:

After inhalation:
Take a fresh air.
Immediately call in physician.

If breathing stops:
Immediately apply artificial respiration, if necessary also oxygen.

In case of skin contact:
Take off immediately all contaminated clothing.
Rinse skin with water/ shower.

In case of eye contact:

After eye contact:
Rinse out with plenty of water.
Immediately call in ophthalmologist.
Remove contact lenses.

If swallowed:

After swallowing:
Immediately make victim drink water (two glasses at most).
Consult a physician.

Indication of any immediate medical attention and special treatment needed:
No data available

Firefighting measures of Cupric Hydrate:

Suitable extinguishing media:
Use extinguishing measures that are appropriate to local circumstances and the surrounding environment.

Unsuitable extinguishing media:
For this substance/mixture no limitations of extinguishing agents are given.

Special hazards arising from the substance or mixture:
Copper oxides
Not combustible.
Ambient fire may liberate hazardous vapours.

Advice for firefighters:
Stay in danger area only with self-contained breathing apparatus.
Prevent skin contact by keeping a safe distance or by wearing suitable protective clothing.

Further information:
Prevent fire extinguishing water from contaminating surface water or the ground water system.

Accidental release measures of Cupric Hydrate:

Personal precautions, protective equipment and emergency procedures:

Advice for non-emergency personnel:
Avoid generation and inhalation of dusts in all circumstances.
Avoid substance contact.

Ensure adequate ventilation.
Evacuate the danger area, observe emergency procedures, consult an expert.

Environmental precautions:
Do not let product enter drains.

Methods and materials for containment and cleaning up:
Cover drains.
Collect, bind, and pump off spills.

Observe possible material restrictions.
Take up carefully.

Dispose of properly.
Clean up affected area.
Avoid generation of dusts.

Exposure controls/personal protection of Cupric Hydrate:

Personal protective equipment:

Eye/face protection:
Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).
Tightly fitting safety goggles.

Skin protection:
This recommendation applies only to the product stated in the safety data sheet, supplied by us and for the designated use.
When dissolving in or mixing with other substances and under conditions deviating from those stated in EN 16523-1 please contact the supplier of CE-approved gloves.

Full contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 480 min
Material tested:KCL 741 Dermatril® L

Splash contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 480 min
Material tested:KCL 741 Dermatril® L

Body Protection:
protective clothing

Respiratory protection:
required when dusts are generated.

Our recommendations on filtering respiratory protection are based on the following standards:
DIN EN 143, DIN 14387 and other accompanying standards relating to the used respiratory protection system.

Recommended Filter type: Filter type P3
The entrepeneur has to ensure that maintenance, cleaning and testing of respiratory protective devices are carried out according to the instructions of the producer.
These measures have to be properly documented.

Control of environmental exposure:
Do not let product enter drains

Identifiers of Cupric Hydrate:
CAS Number: 20427-59-2
ChemSpider: 144498
ECHA InfoCard: 100.039.817
KEGG: C18712
PubChem CID: 164826
UNII: 3314XO9W9A
CompTox Dashboard (EPA): DTXSID6034473
InChI:
InChI=1S/Cu.2H2O/h;2*1H2/q+2;;/p-2
Key: JJLJMEJHUUYSSY-UHFFFAOYSA-L
InChI=1/Cu.2H2O/h;2*1H2/q+2;;/p-2
Key: JJLJMEJHUUYSSY-NUQVWONBAH
SMILES: [Cu+2].[OH-].[OH-]

Linear Formula: Cu(OH)2
MDL Number: MFCD00010968
EC No.: 243-815-9
Beilstein/Reaxys No.: N/A
Pubchem CID: 164826
IUPAC Name: copper dihydroxide
SMILES: [Cu+2].[OH-].[OH-]
InchI Identifier: InChI=1S/Cu.2H2O/h;2*1H2/q+2;;/p-2
InchI Key: JJLJMEJHUUYSSY-UHFFFAOYSA-L

Properties of Cupric Hydrate:
Chemical formula: Cu(OH)2
Molar mass: 97.561 g/mol
Appearance: Blue or blue-green solid
Density: 3.368 g/cm3, solid
Melting point: 80 °C (176 °F; 353 K) approximate, decomposes into CuO
Solubility in water: negligible
Solubility product (Ksp): 2.20 x 10−20[1]
Solubility:
İnsoluble in ethanol;
Soluble in NH4OH
Magnetic susceptibility (χ): +1170.0·10−6 cm3/mol

Cu(OH)2: Cupric hydrate
Density: 3.37 g/cm³
Molecular Weight/ Molar Mass: 97.561 g/mol
pH: 7.69
Melting Point: 80° C
Chemical Formula: Cu(OH)2

Odour: Fishy odour
Appearance: Blue or bluish green solid
Covalently-Bonded Unit: 3
Heavy Atom Count: 3
Hydrogen Bond Acceptor: 2
Solubility: Insoluble in water

Molecular Weight: 99.58:
Hydrogen Bond Donor Count: 2:
Hydrogen Bond Acceptor Count: 2:
Rotatable Bond Count: 0:
Exact Mass: 98.950726:
Monoisotopic Mass: 98.950726:
Topological Polar Surface Area: 2 Å²:
Heavy Atom Count: 3:
Complexity: 2.8:
Isotope Atom Count: 0:
Defined Atom Stereocenter Count: 0:
Undefined Atom Stereocenter Count: 0:
Defined Bond Stereocenter Count: 0:
Undefined Bond Stereocenter Count: 0:
Covalently-Bonded Unit Count: 3:
Compound Is Canonicalized: Yes

Thermochemistry of Cupric Hydrate:
Std molar entropy (So298): 108 J·mol−1·K−1
Std enthalpy of formation (ΔfH⦵298): −450 kJ·mol−1

Related compounds of Cupric Hydrate:
Copper(I) oxide
Copper(I) chloride

Other anions:
Copper(II) oxide
Copper(II) carbonate
Copper(II) sulfate
Copper(II) chloride

Other cations:
Nickel(II) hydroxide
Zinc hydroxide
Iron(II) hydroxide
Cobalt hydroxide

Names of Cupric Hydrate:

IUPAC name:
Copper(II) hydroxide

Other name:
Cupric hydroxide

MeSH of Copper hydroxide:
Cu(OH)2
cupric hydroxide