CAS NUMBER: 1305-62-0
EC NUMBER: 215-137-3
MOLECULAR FORMULA: Ca(OH)₂
MOLECULAR WEIGHT: 74.1 g/mol
E526 (Calcium hydroxide) is an inorganic compound with the chemical formula Ca(OH)2.
E526 (Calcium hydroxide) is a colorless crystal or white powder and is produced when quicklime (calcium oxide) is mixed or slaked with water.
E526 (Calcium hydroxide) has many names including hydrated lime, caustic lime, builders' lime, slaked lime, cal, and pickling lime.
E526 (Calcium hydroxide) is an odorless white powder.
E526 (Calcium hydroxide)’s used in industrial settings, such as sewage treatment, paper production, construction, and food processing.
E526 (Calcium hydroxide) also has medical and dental uses.
For example, root canal fillings often contain E526 (Calcium hydroxide).
E526 (Calcium hydroxide), also called slaked lime, Ca(OH)2, is obtained by the action of water on calcium oxide.
When mixed with water, a small proportion of it dissolves, forming a solution known as E526 (Calcium hydroxide), the rest remaining as a suspension called milk of lime.
E526 (Calcium hydroxide) is used as an industrial alkali and as a constituent of mortars, plasters, and cement.
E526 (Calcium hydroxide) is used in the kraft paper process and as a flocculant in sewage treatment.
Calcium dihydroxide is a E526 (Calcium hydroxide).
E526 (Calcium hydroxide) has a role as an astringent.
White, odorless powder.
E526 (Calcium hydroxide), Ca(OH)2, has a long history of use in dentistry for pulp capping and it is available in a number of forms.
These include as a supersaturated solution, a hard setting cement and also a light-curable material.
E526 (Calcium hydroxide)s key feature is its high alkalinity (pH 11–12.5), and this can be achieved using E526 (Calcium hydroxide) powder mixed with pure water to the consistency of a light paste.
However, used in this way, E526 (Calcium hydroxide) does not set, has no mechanical strength and consequently there is the danger of it being displaced by the forces involved in placing a restorative material over it.
Also in this form it cannot be used directly under any resin-based restoration (composite resins, compomers and resin-modified glass-ionomers) because it is hydrophilic and would interfere with bonding systems.
To overcome this problem, E526 (Calcium hydroxide) formulations that are capable of undergoing some sort of setting reaction, and thus building up a degree of mechanical strength, are generally used.
However, they have slightly different properties and cannot replace supersaturated E526 (Calcium hydroxide) solutions in all clinical situations.
E526 (Calcium hydroxide) is the most available and lowest cost of the metal hydroxides and has a very significant endothermic decomposition at a temperature which, although a little on the high side, ought to be suitable for some polymers.
As such, E526 (Calcium hydroxide) has attracted some interest as a possible flame retardant additive.
E526 (Calcium hydroxide) is a highly water insoluble crystalline Calcium source for uses compatible with higher (basic) pH environments.
E526 (Calcium hydroxide) 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.
E526 (Calcium hydroxide) was originally introduced to the field of endodontics by Herman1 in 1930 as a pulp-capping agent, but its uses today are widespread in endodontic therapy.
E526 (Calcium hydroxide) is the most commonly used dressing for treatment of the vital pulp.
E526 (Calcium hydroxide) also plays a major role as an intervisit dressing in the disinfection of the root canal system.
E526 (Calcium hydroxide) crystals form via a nonclassical crystallization process involving prenucleation ion associates, dense liquid nanodroplets, amorphous nanostructured precursor, and metastable and stable crystalline phases.
This complex multistep crystallization behavior is affected by organic additives that modify the stability of pre- and postnucleation entities, eliciting nonclassical nucleation and growth processes that have implications in a range of systems, including cement.
E526 (Calcium hydroxide) (CH or portlandite) has numerous important technical, biomedical, and industrial applications and is the main component of traditional lime mortars and plasters used for building purposes since the advent of pyrotechnology ca. 12 000 years ago.
E526 (Calcium hydroxide) is also a substantial component (20–25 wt %) of set Portland cement, the man-made material most massively produced and consumed in the world.
During cement hydration, E526 (Calcium hydroxide) forms via the reaction Ca2+ + 2OH– = Ca(OH)2, following dissolution of alite (tricalcium silicate or C3S; main anhydrous phase of Portland cement) and belite (dicalcium silicate or β-C2S).
E526 (Calcium hydroxide) is believed to have a profound effect on the formation of calcium silicate hydrate (CSH), the main phase in set cement.
Moreover, E526 (Calcium hydroxide) crystal morphology, microstructure, and distribution play a key role on the physical–mechanical properties of set cement and its durability.
Consequently, a good understanding of the formation of E526 (Calcium hydroxide) is of paramount importance to evaluate, predict, and improve materials performance and avoid premature degradation.
E526 (Calcium hydroxide) is commonly used to prepare lime mortar.
One significant application of E526 (Calcium hydroxide) is as a flocculant, in water and sewage treatment.
E526 (Calcium hydroxide) forms a fluffy charged solid that aids in the removal of smaller particles from water, resulting in a clearer product.
This application is enabled by the low cost and low toxicity of E526 (Calcium hydroxide).
E526 (Calcium hydroxide) is also used in fresh-water treatment for raising the pH of the water so that pipes will not corrode where the base water is acidic, because it is self-regulating and does not raise the pH too much.
Another large application is in the paper industry, where it is an intermediate in the reaction in the production of sodium hydroxide.
This conversion is part of the causticizing step in the Kraft process for making pulp.
In the causticizing operation, burned lime is added to green liquor, which is a solution primarily of sodium carbonate and sodium sulfate produced by dissolving smelt, which is the molten form of these chemicals from the recovery furnace.
E526 (Calcium hydroxide) is used in the construction industry as part of mortar, since its reaction with carbon dioxide of the air binds the particles of sand and gravel by forming calcium carbonate.
Another major applications are the usage of E526 (Calcium hydroxide) as a flocculant in water and sewage treatment, and the recovery of sodium hydroxide in the paper industry.
-In USDA certified food production in plants and livestock
-To clarify raw juice from sugarcane or sugar beets in the sugar industry, (see carbonatation)
-To process water for alcoholic beverages and soft drinks
-Pickle cucumbers and other foods
-To make Chinese century eggs
-In maize preparation: removes the cellulose hull of maize kernels (see nixtamalization)
-To clear a brine of carbonates of calcium and magnesium in the manufacture of salt for food and pharmaceutical uses
-In fortifying (Ca supplement) fruit drinks, such as orange juice, and infant formula
-As a digestive aid (called Choona, used in India in paan, a mixture of areca nuts, E526 (Calcium hydroxide) and a variety of seeds wrapped in betel leaves)
-As a substitute for baking soda in making papadam
-In the removal of carbon dioxide from controlled atmosphere produce storage rooms
-In the preparation of mushroom growing substrates
At ambient temperature, E526 (Calcium hydroxide) dissolves in pure water to produce an alkaline solution with a pH of about 12.5.
E526 (Calcium hydroxide) solutions can cause chemical burns.
At high pH value due to a common-ion effect with the hydroxide anion OH−, its solubility drastically decreases.
This behavior is relevant to cement pastes.
Aqueous solutions of E526 (Calcium hydroxide) are called limewater and are medium-strength bases, which reacts with acids and can attack some metals such as aluminium (amphoteric hydroxide dissolving at high pH), while protecting other metals, such as iron and steel, from corrosion by passivation of their surface.
-CAS number: 1305-62-0
-EC number: 215-137-3
-Grade: ACS,Reag. Ph Eur
-Hill Formula: H₂CaO₂
-Chemical formula: Ca(OH)₂
-Molar Mass: 74.1 g/mol
-HS Code: 2825 90 19
PHYSICAL AND CHEMICAL PROPERTIES:
-Density: 2.240 g/cm3 (20 °C)
-Melting Point: >=450 °C (decomposition)
-pH value: 12.6 (H₂O, 20 °C) (saturated solution)
-Bulk density: 400 kg/m3
-Solubility: 1.7 g/l
-Compound Formula: H2CaO2
-Molecular Weight: 74.09
-Appearance: White Powder
-Melting Point: 580° C (1,076° F)
-Density: 2.24 g/cm3
-Exact Mass: 73.968071
-Monoisotopic Mass: 73.968071
E526 (Calcium hydroxide) adopts a polymeric structure, as do all metal hydroxides.
Strong hydrogen bonds exist between the layers.
In the laboratory E526 (Calcium hydroxide) can be prepared by mixing aqueous solutions of calcium chloride and sodium hydroxide.
The mineral form, portlandite, is relatively rare but can be found in some volcanic, plutonic, and metamorphic rocks.
E526 (Calcium hydroxide) has also been known to arise in burning coal dumps.
The positively charged ionized species CaOH+ has been detected in the atmosphere of S-type stars.
-density: 2.24 g/mL at 25 °C (lit.)
-SMILES string: O[Ca]O
-InChI key: AXCZMVOFGPJBDE-UHFFFAOYSA-
-Linear Formula: Ca(OH)2
-MDL Number: MFCD00010901
-EC No.: 215-137-3
-Pubchem CID: 6093208
-IUPAC Name: calcium dihydroxide
-InchI Identifier: InChI=1S/Ca.2H2O/h;2*1H2/q+2;;/p-2
-InchI Key: AXCZMVOFGPJBDE-UHFFFAOYSA-L
E526 (Calcium hydroxide) (Ca(OH)2)
Calcium Oxide, Hydrated
E526 (Calcium hydroxide) USP/FCC
E526 (Calcium hydroxide) ACS grade
E526 (Calcium hydroxide) Topical Solution