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E927b CARBAMIDE

E927b Carbamide is used as a raw material for construction chemicals.
E927b Carbamide is used as a raw material for household chemicals production.
E927b Carbamide is mainly used as a flour treatment agent, humectant, texture stabilizer, and processing aid in specific food applications, especially sugar-free chewing gum.

CAS-Number : 57-13-6
EC-Number : 200-315-5
Molecular Formula: CH4N2O.H2O2 or CH6N2O3
Molecular Weight: 94.07 g/mol

SYNONYMS:
Urea hydrogen peroxide, CARBAMIDE PEROXIDE, Percarbamide, Urea peroxide, Urea dioxide, Urea hydroperoxide, Hydroperit, Hydroperite, Percarbamid, Perhydrit, Thenardol, Hyperol, Ortizon, Perhydrol-Urea, Hydrogen peroxide carbamide, Hydrogen peroxide urea, Urea compound with hydrogen peroxide (1:1), Carbamide peroxide, solution, hydrogen peroxide, urea, UNII-31PZ2VAU81, Urea hydrogen peroxide adduct, Hydrogen peroxide-Urea adduct, Carbamide peroxide [USP], Urea, compd. with hydrogen peroxide (H2O2) (1:1), 31PZ2VAU81, Urea, compd. with hydrogen peroxide (1:1), CHEBI:75178, Carbamide peroxide (USP), Murine Ear Drops, hydrogen peroxide, urea, Proxigel, Debrox, Gly-oxide, Thera-ear, Ear Wax Treatment, Ureahydrogenperoxide, Auro Ear Wax Remover, NSC 24852, UN1511, per carbamide, Hydrogen peroxide, compd. with urea (1:1), Carbamide Peroxide Otic Solution, urea-hydrogen peroxide, urea.H2O2, Hydrogen peroxide.Urea, H2O2 Urea, Murine ear drops (TN), DSSTox_CID_4726, WLN: ZVZ & QQ, DSSTox_RID_77512, DSSTox_GSID_24726, hydrogen peroxide urea adduct, CH6N2O3, Urea hydrogen peroxide, 97%, CHEMBL3184026, DTXSID9024726, hydrogen peroxide - urea (1:1), Urea, compd. with peroxide (1:), NSC24852, Tox21_302451, Urea compound with hydrogen peroxide, NSC-24852, Hydrogen peroxide-Urea adduct, tablet, AKOS015904087, DB11129, Hydrogen Peroxide Urea, Perhydrol-Urea, Hydrogen peroxide-urea compound (1:1), NCGC00256660-01, (H2 N)2 C O (H2 O2), Hydrogen peroxide, compd. with urea(1:1), Urea, compd. with hydrogen peroxide(1:1), X9583, D03383, Urea hydrogen peroxide, A805233, J-005078, J-525152, Q-200793, Q2633879, Hydrogen peroxide-Urea adduct, USP, 96.0-102.0%, Hydrogen peroxide-Urea adduct, powder, 15-17% active oxygen basis, Hydrogen peroxide-Urea adduct, purum p.a., "rapid-soluble", tablet (1 g each), UHP, Urea, Systematic IUPAC name, Carbonic diamide, Carbamide, Carbonyldiamide, Carbonyldiamine, Diaminomethanal, Diaminomethanone, Carbamide, Urea, Carbonyldiamide, Carbonyl diamide, Carbonyldiamine, Isourea, Ureophil, Ureaphil, Harnstoff, E927b, INS 927b

Carbamide, commonly known as E927b Carbamide, is an organic compound used in the food industry under the additive code E927b.
E927b Carbamide is naturally produced in the body as the final product of protein metabolism, but industrial carbamide is synthetically manufactured from ammonia and carbon dioxide.

E927b Carbamide appears as a white crystalline solid that is highly soluble in water and exhibits low odor under normal conditions.
E927b Carbamide is an organic chemical compound, more precisely a diamide of carbonic acid.
E927b Carbamide has in its structure two amino groups connected by a functional carbonyl group.

E927b Carbamide occurs naturally in the body as an end product of the metabolism of proteins and other nitrogenous compounds and is excreted in urine and in small amounts in sweat.
E927b Carbamide is also obtained synthetically by the direct reaction of carbon dioxide with ammonia.

E927b Carbamide is also known as carbamide and has the symbol E927b as a food additive.
E927b Carbamide is obtained from ammonia and carbon dioxide.
E927b Carbamide is a substance that occurs naturally in the body.

E927b Carbamide is the same substance found in urine.
Although E927b Carbamide is a naturally occurring compound, for industrial use it is usually produced synthetically from ammonia and carbon dioxide.
As a food additive, E927b Carbamide is permitted in the EU exclusively in sugar-free chewing gum.

Remarkably little is known about the safety of E927b Carbamide as a food additive.
Additionally, E927b Carbamide is stated that it has a mild diuretic effect.
E927b Carbamide is a waste product found in the blood resulting from the normal breakdown of proteins in the liver.

E927b Carbamide is a humectant and flavor enhancer.
Adults excrete E927b Carbamide daily, and studies conducted to date have not shown any adverse effects related to the use of this additive.
E927b Carbamide is a natural substance found in abundance in urine.

E927b Carbamide improves the taste and chewing properties of sugar-free chewing gum.
E927b Carbamide is an important fertilizer.
E927b Carbamide is a versatile chemical compound used extensively in various industries, including food, pharmaceuticals, agriculture, and manufacturing.

E927b Carbamide is valued for its nitrogen content and numerous functional properties.
E927b Carbamide is a highly versatile and essential compound in multiple industries.
E927b Carbamide's roles as a food additive, pharmaceutical ingredient, fertilizer, and industrial chemical highlight its importance and wide-ranging applications.

With its beneficial properties and safety, E927b Carbamide continues to be a valuable ingredient in enhancing product quality and supporting various industrial processes.
E927b Carbamide, also known as urea, designated in the food industry as E927b, is an organic chemical compound used as a food additive.

Although E927b Carbamide occurs naturally in the human body as a product of protein metabolism, in industrial applications it is usually produced synthetically.
E927b Carbamide is a food additive added to sugar-free chewing gum.
E927b Carbamide (because it is a diamide of carbonic acid), is an organic compound with chemical formula CO(NH2)2.

E927b Carbamide has two amino groups (−NH2) joined by a carbonyl functional group (−C(=O)−).
E927b Carbamide is thus the simplest amide of carbamic acid.
E927b Carbamide serves an important role in the cellular metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals.

The word E927b Carbamide is Neo-Latin, from French urée, from Ancient Greek οὖρον (oûron) 'urine'.
E927b Carbamide is a colorless, odorless solid, highly soluble in water, and practically non-toxic.
Dissolved in water, E927b Carbamide is neither acidic nor alkaline.
The body uses E927b Carbamide in many processes, most notably nitrogen excretion.

In the liver, E927b Carbamide forms by the condensation of ammonia (NH3) and carbon dioxide (CO2) in the E927b Carbamide cycle.
In 1828, Friedrich Wöhler discovered that E927b Carbamide can be produced from inorganic starting materials, an important conceptual milestone in chemistry.

This showed for the first time that a substance previously known only as a byproduct of life could be synthesized in the laboratory from non-biological starting materials, thereby contradicting the widely held doctrine of vitalism, which stated that organic compounds could only be derived from living organisms.

E927b Carbamide is an organic chemical compound that is obtained industrially from ammonium hydrate and carbon dioxide.
E927b Carbamide appears in the form of a white powder.

USES and APPLICATIONS of E927b CARBAMIDE:
E927b Carbamide is used as a raw material for the horticultural industry.
E927b Carbamide is used as a raw material for dairy processing.
In the food context, E927b Carbamide is used for its unique properties, such as its ability to increase foam stability in carbonated beverages and as an ingredient that facilitates the processing of certain products.

E927b Carbamide is distinguished by its ability to regulate the consistency and texture of food products.
E927b Carbamide is particularly valued in the production of carbonated beverages for its ability to stabilize and increase foam stability.

In addition, E927b Carbamide can serve as a moisturizing ingredient in dry products, improving their texture.
E927b Carbamide is mainly used in the production of carbonated beverages, where it helps maintain and increase foam stability.
E927b Carbamide is also used in some bakery and pastry products as a moistening agent, helping to keep them fresh and soft for longer.

Because of its hygroscopic and moisture-retaining properties, E927b Carbamide is widely used not only in food processing but also in cosmetics, pharmaceuticals, agriculture, animal nutrition, resins, adhesives, and industrial chemistry.
E927b Carbamide is considered chemically stable under standard storage conditions and demonstrates broad industrial versatility.

E927b Carbamide is primarily used in the food industry as a flour treatment agent and humectant.
In the European Union, E927b Carbamide is mainly permitted in sugar-free chewing gum formulations.
E927b Carbamide helps soften chewing gum textcarbamidend contributes to moisture retention and stability during storage.

E927b Carbamide also helps neutralize acids in the mouth, which may contribute to reduced risk of dental caries.
In fermentation industries, E927b Carbamide may serve as a nitrogen source for yeast and microbial growth during production of wines, spirits, and fermented beverages.
E927b Carbamide is widely used in agricultcarbamides one of the world’s most important nitrogen fertilizers because of its very high nitrogen content.

In industrial chemistry, Carbamide is used in the production of E927b Carbamide-formaldehyde resins, adhesives, laminates, plastics, coatings, textiles, and molding compounds.
E927b Carbamide is extensively used in pharmaceuticals and cosmetics.
Dermatological creams containing E927b Carbamide are commonly used for skin hydration, keratolytic treatments, dry skin therapy, eczema management, and foot care products.

In cosmetics, E927b Carbamide acts as a moisturizing and skin-softening agent.
E927b Carbamide is also used in animal feed, laboratory reagents, diesel exhaust fluid systems, medical formulations, and cryoprotective solutions.
E927b Carbamide is used as a raw material for paint and varnish production.

E927b Carbamide is used as a raw material for adhesives. oils. and lubricants production.
Uses of E927b Carbamide: Baked goods, chewing gum, pretzels
Other Uses of E927b Carbamide: Roll on deodorant, shampoo, mouthwash, hair colouring

E927b Carbamide is used as nutrient in fermented products.
E927b Carbamide is used to bleach teeth as a teeth whitener and to inhibit potato sprouting.
E927b Carbamide is also used in bread as a browning agent.

E927b Carbamide is also used in fertilisers as a source of nitrogen.
E927b Carbamide is a synthetic compound utilized in the food industry, particularly in the production of sugar-free chewing gum.
E927b Carbamide serves as a stabilizer for the chewing mass, enhancing and moisture retention.

E927b Carbamide is used as a raw material for fertilizer production.
E927b Carbamide is used as a raw material for plastics production.
Food uses of E927b Carbamide: Ingredient listed in the European food additives list as E927b as acidity regulator, anti-caking agent.

E927b Carbamide is a solid fertiliser with good nitrogen content in main and supplementary fertilisation of crops.
E927b Carbamide is used in the chemical industry for the production of formaldehyde and in low temperature thermochemical cyanidation.
E927b Carbamide is used cosmetic raw material.

E927b Carbamide is used feed raw material.
Stabilizer in Chewing Gum: E927b Carbamide is incorporated into sugar-free chewing gums to stabilize the chewing mass, ensuring consistent and prolonging shelf life.
E927b Carbamide is used exclusively in sugar-free chewing gum at a maximum concentration of 30 g/kg.

E927b Carbamide makes the gum smoother and softens the taste.
Under certain conditions of use, sugar-free chewing gum with added E927b Carbamide may prevent cavities and neutralize plaque acids more effectively than chewing gum without E927b Carbamide.
E927b Carbamide, is of unknown origin and is used as a flour treatment agent.

Resins: E927b Carbamide is a raw material for the manufacture of formaldehyde based resins, such as UF, MUF, and MUPF, used mainly in wood-based panels, for instance, particleboard, fiberboard, OSB, and plywood.
E927b Carbamide is widely used in fertilizers as a source of nitrogen (N).

-Explosives use of E927b Carbamide:
E927b Carbamide can be used in a reaction with nitric acid to make E927b Carbamide nitrate, a high explosive that is used industrially and as part of some improvised explosive devices."

-Automobile systems use of E927b Carbamide:
E927b Carbamide is used in Selective Non-Catalytic Reduction (SNCR) and Selective Catalytic Reduction (SCR) reactions to reduce the NOx pollutants in exhaust gases from diesel, dual fuel, and lean-burn natural gas engines.

The BlueTec system, for example, injects a water-based E927b Carbamide solution into the exhaust system.
Ammonia (NH3) produced by the hydrolysis of E927b Carbamide reacts with nitrogen oxides (NOx) and is converted into nitrogen gas (N2) and water within the catalytic converter.

The conversion of noxious NOx to innocuous N2 is described by the following simplified global equation:
4 NO + 4 NH3 + O2 → 4 N2 + 6 H2O
When E927b Carbamide is used, a pre-reaction (hydrolysis) occurs to first convert it to ammonia:
CO(NH2)2 + H2O → 2 NH3 + CO2

Being a solid highly soluble in water (1200 g/L at 25 °C (77 °F)), E927b Carbamide is much easier and safer to handle and store than the more irritant, caustic and hazardous ammonia, so it is the reactant of choice.
Trucks and cars using these catalytic converters need to carry a supply of diesel exhaust fluid, also sold as AdBlue, a solution of E927b Carbamide in water.

-Laboratory uses of E927b Carbamide:
E927b Carbamide in concentrations up to 10 M is a protein denaturant as it disrupts the noncovalent bonds in the proteins.
This property can be exploited to increase the solubility of some proteins.
A mixture of E927b Carbamide and choline chloride is used as a deep eutectic solvent (DES), a substance similar to ionic liquid.
When used in a deep eutectic solvent, E927b Carbamide gradually denatures the proteins that are solubilized.

E927b Carbamide in concentrations up to 8 M can be used to make fixed brain tissue transparent to visible light while still preserving fluorescent signals from labeled cells.
This allows for much deeper imaging of neuronal processes than previously obtainable using conventional one photon or two photon confocal microscopes

-Agriculture uses of E927b Carbamide:
More than 90% of world industrial production of E927b Carbamide is for use as a nitrogen-release fertilizer.
E927b Carbamide has the highest nitrogen content of all solid nitrogenous fertilizers in common use.
Therefore, it has a low transportation cost per unit of nitrogen nutrient.

E927b Carbamide breaks down in the soil to give ammonium ions (NH+4).
E927b Carbamide is taken up by the plant through its roots.

In some soils, the ammonium is oxidized by bacteria to give nitrate (NO−3), which is also a nitrogen-rich plant nutrient.
The loss of nitrogenous compounds to the atmosphere and runoff is wasteful and environmentally damaging so E927b Carbamide is sometimes modified to enhance the efficiency of its agricultural use.

Techniques to make controlled-release fertilizers that slow the release of nitrogen include the encapsulation of E927b Carbamide in an inert sealant, and conversion of E927b Carbamide into derivatives such as E927b Carbamide-formaldehyde compounds, which degrade into ammonia at a pace matching plants' nutritional requirements.
The most common impurity of synthetic E927b Carbamide is biuret, which impairs plant growth

-Medical use of E927b Carbamide:
E927b Carbamide-containing creams are used as topical dermatological products to promote rehydration of the skin.
E927b Carbamide 40% is indicated for psoriasis, xerosis, onychomycosis, ichthyosis, eczema, keratosis, keratoderma, corns, and calluses.
If covered by an occlusive dressing, 40% E927b Carbamide preparations may also be used for nonsurgical debridement of nails.

E927b Carbamide 40% "dissolves the intercellular matrix" of the nail plate.
Only diseased or dystrophic nails are removed, as there is no effect on healthy portions of the nail.
E927b Carbamide has been studied as a diuretic.

E927b Carbamide was first used by Dr. W. Friedrich in 1892.
In a 2010 study of ICU patients, E927b Carbamide was used to treat euvolemic hyponatremia and was found safe, inexpensive, and simple.

Like saline, E927b Carbamide has been injected into the uterus to induce abortion, although this method is no longer in widespread use.
The blood E927b Carbamide nitrogen (BUN) test is a measure of the amount of nitrogen in the blood that comes from E927b Carbamide.

It is used as a marker of renal function, though it is inferior to other markers such as creatinine because blood E927b Carbamide levels are influenced by other factors such as diet, dehydration, and liver function.
E927b Carbamide has also been studied as an excipient in drug-coated balloon (DCB) coating formulations to enhance local drug delivery to stenotic blood vessels.

E927b Carbamide, when used as an excipient in small doses (~3 μg/mm2) to coat DCB surface was found to form crystals that increase drug transfer without adverse toxic effects on vascular endothelial cells.
E927b Carbamide labeled with carbon-14 or carbon-13 is used in the E927b Carbamide breath test, which is used to detect the presence of the bacterium Helicobacter pylori (H. pylori) in the stomach and duodenum of humans, associated with peptic ulcers.

The test detects the characteristic enzyme E927b Carbamidese, produced by H. pylori, by a reaction that produces ammonia from E927b Carbamide.
This increases the pH (reduces the acidity) of the stomach environment around the bacteria.
Similar bacteria species to H. pylori can be identified by the same test in animals such as apes, dogs, and cats (including big cats)

BENEFITS AND USES of E927b CARBAMIDE:
Food Additive:
In the food industry, E927b Carbamide is used as a dough conditioner to improve the texture and volume of baked goods.
It helps in the fermentation process, leading to better-quality products.

Pharmaceutical Grade:
E927b Carbamide is utilized in the pharmaceutical industry for its role in protein synthesis and as an excipient in various formulations.
E927b Carbamide is also used in topical creams and ointments for its moisturizing properties.

Dough Conditioner:
As a dough conditioner, E927b Carbamide enhances the elasticity and extensibility of dough, making it easier to process and resulting in improved final product quality.

Fertilizer:
In agriculture, E927b Carbamide is a key component of fertilizers, providing a readily available source of nitrogen to plants, which is essential for their growth and development.

Protein Synthesis:
In the body, E927b Carbamide plays a critical role in the synthesis of proteins and other nitrogen-containing compounds, making it an important nutrient in dietary supplements and animal feeds.

Industrial Use:
E927b Carbamide is also used in various industrial applications, such as in the production of plastics, resins, and adhesives.
Its chemical properties make E927b Carbamide suitable for a wide range of manufacturing processes.

Nitrogen Source:
As a nitrogen-rich compound, E927b Carbamide is an effective and efficient source of nitrogen for various applications, including soil conditioning, wastewater treatment, and more.

Usage and Safety
E927b Carbamide is widely recognized as safe for use in food, pharmaceutical, and agricultural products.
It is approved by regulatory agencies and is used in controlled quantities to ensure safety and effectiveness.

BENEFITS of E927b CARBAMIDE:
E927b Carbamide provides excellent moisture-retention properties.
E927b Carbamide improves texture stability in chewing gum and processed products.
E927b Carbamide helps reduce drying and hardening in formulations.

E927b Carbamide has very high water solubility.
E927b Carbamide is highly economical and widely available.
E927b Carbamide provides a concentrated nitrogen source for industrial and agricultural applications.

E927b Carbamide contributes to acid neutralization in oral-care applications.
E927b Carbamide demonstrates broad compatibility with aqueous systems.
E927b Carbamide supports microbial fermentation processes.

E927b Carbamide provides effective humectant functionality in cosmetic and pharmaceutical systems.
E927b Carbamide exhibits good shelf stability under proper storage conditions.
E927b Carbamide is biodegradable and naturally involved in nitrogen metabolism.

MOLECULAR AND CRYSTAL STRUCTURE of E927b CARBAMIDE:
The structure of the molecule of E927b Carbamide is O=C(−NH2)2.
The E927b Carbamide molecule is planar when in a solid crystal because of sp2 hybridization of the N orbitals.
E927b Carbamide is non-planar with C2 symmetry when in the gas phase or in aqueous solution, with C−N−H and H−N−H bond angles that are intermediate between the trigonal planar angle of 120° and the tetrahedral angle of 109.5°.

In solid E927b Carbamide, the oxygen center is engaged in two N−H−O hydrogen bonds.
The resulting hydrogen-bond network is probably established at the cost of efficient molecular packing:
The structure is quite open, the ribbons forming tunnels with square cross-section.

The carbon in E927b Carbamide is described as sp2 hybridized, the C−N bonds have significant double bond character, and the carbonyl oxygen is relatively basic.
E927b Carbamide's high aqueous solubility reflects its ability to engage in extensive hydrogen bonding with water.
By virtue of its tendency to form porous frameworks, E927b Carbamide has the ability to trap many organic compounds.

In these so-called clathrates, the organic "guest" molecules are held in channels formed by interpenetrating helices composed of hydrogen-bonded E927b Carbamide molecules.
In this way, E927b Carbamide-clathrates have been well investigated for separations

E927b CARBAMIDE AND ITS FUNCTIONS IN FOOD:
As a food additive, E927b Carbamide plays a key role in improving the quality and sensory properties of food products.
By stabilizing foam in carbonated beverages and acting as a humectant in dry products, E927b Carbamide contributes to consumer satisfaction with consumed products.

CHARACTERISTICS of E927b CARBAMIDE:
E927b Carbamide is one of the simplest organic amides.
E927b Carbamide naturally occurs in mammals as a metabolic waste product formed in the liver during the E927b Carbamide cycle.
Industrial E927b Carbamide is synthetically produced by reacting ammonia with carbon dioxide under high presscarbamidend temperature conditions.

E927b Carbamide demonstrates strong hydrogen-bonding ability because of its amide groups.
E927b Carbamide is highly hygroscopic and readily absorbs moisture from the environment.

E927b Carbamide is chemically stable under dry storage conditions but may slowly decompose under heat or moisture exposure.
When heated strongly, E927b Carbamide may release ammonia and form biuret and related compounds.
E927b Carbamide exhibits excellent compatibility with water-based formulations.

E927b Carbamide possesses mild keratolytic activity, which explains its widespread use in dermatological preparations.
E927b Carbamide has relatively low toxicity at approved food and industrial exposure levels.
CarbE927b Carbamide amide was first isolated from urine in the 18th century.

In 1828, Friedrich Wöhler synthesized E927b Carbamide artificially from ammonium cyanate, which became one of the most historically important discoveries in organic chemistry.
This experiment demonstrated that organic compounds could be synthesized from inorganic substances and helped establish modern organic chemistry.

E927b Carbamide plays a central biological role in nitrogen excretion in humans and animals.
The human liver converts toxic ammonia into E927b Carbamide, which is then safely excreted through urine.
Because of its high nitrogen concentration, Carbamide remains one of the most important nitrogen fertilizers globally.

REACTIONS of E927b CARBAMIDE:
Basicity
E927b Carbamide is a weak base, with a pKb of 13.9.
When combined with strong acids, it undergoes protonation at oxygen to form uronium salts.
E927b Carbamide is a Lewis base, forming metal complexes of the type [M(E927b Carbamide)6]n+.

N-functionalization
As an electron-rich amide, E927b Carbamide readily undergoes N-functionalization by electrophilic reagents.
This property gives rise to several reagents.
Nitration occurs at the amine to give N-nitroE927b Carbamide.
Chlorination similarly gives N-chloroE927b Carbamide.

Transamination
E927b Carbamide undergoes transamination.
For example, treatment with anilinium gives both N-phenylE927b Carbamide and N,N'-diphenylE927b Carbamide.
N-MethylE927b Carbamide can be prepared by a similar acid-catalyzed pathway.

Heterocyclization
E927b Carbamide, being a multifunctional, is a versatile precursor to heterocycles.
E927b Carbamide reacts with malonic esters to make barbituric acids.
With hydroxyketones, E927b Carbamide condenses to give glyoxalones.
E927b Carbamide is a precursor to pyrimidines.

Thermolysis
Molten E927b Carbamide decomposes into ammonium cyanate at about 152 °C (306 °F), and into ammonia and isocyanic acid above 160 °C (320 °F):
CO(NH2)2 → [NH4]+[OCN]− → NH3 + HNCO

Heating above 160 °C (320 °F) yields biuret NH2CONHCONH2 and triuret NH2CONHCONHCONH2 via reaction with isocyanic acid:
CO(NH2)2 + HNCO → NH2CONHCONH2
NH2CONHCONH2 + HNCO → NH2CONHCONHCONH2

At higher temperatures E927b Carbamide converts to a range of condensation products, including cyanuric acid (CNOH)3, guanidine HNC(NH2)2, and melamine.

Hydrolysis
In aqueous solution, E927b Carbamide slowly equilibrates with ammonium cyanate.
This elimination reaction cogenerates isocyanic acid, which can carbamylate proteins, in particular the N-terminal amino group, the side chain amino of lysine, and to a lesser extent the side chains of arginine and cysteine.
Each carbamylation event adds 43 daltons to the mass of the protein, which can be observed in protein mass spectrometry.

For this reason, pure E927b Carbamide solutions should be freshly prepared and used, as aged solutions may develop a significant concentration of cyanate (20 mM in 8 M E927b Carbamide).
Dissolving E927b Carbamide in ultrapure water followed by removing ions (i.e. cyanate) with a mixed-bed ion-exchange resin and storing that solution at 4 °C (39 °F) is a recommended preparation procedure.

However, cyanate will build back up to significant levels within a few days.
Alternatively, adding 25–50 mM ammonium chloride to a concentrated E927b Carbamide solution decreases formation of cyanate because of the common ion effect.

Analysis
E927b Carbamide is readily quantified by a number of different methods, such as the diacetyl monoxime colorimetric method, and the Berthelot reaction (after initial conversion of E927b Carbamide to ammonia via E927b Carbamidese).
These methods are amenable to high throughput instrumentation, such as automated flow injection analyzers and 96-well micro-plate spectrophotometers

RELATED COMPOUNDS of E927b CARBAMIDE:
E927b Carbamide is the parent for a class of chemical compounds that share the same functional group.
Namely, such compounds have a carbonyl group attached to two organic amine residues: R1R2N−C(=O)−NR3R4, where R1, R2, R3 and R4 groups are hydrogen (–H), organyl or other groups.
Examples include carbamide peroxide, allantoin, and hydantoin.
E927b Carbamides are closely related to biurets and related in structure to amides, carbamates, carbodiimides, and thiocarbamides

PHYSIOLOGY of E927b CARBAMIDE:
Amino acids, e.g. from ingested food, can be oxidized by the body as an alternative source of energy, yielding E927b Carbamide and carbon dioxide.
The oxidation pathway starts with the removal of the amino group by a transaminase; the amino group is then fed into the E927b Carbamide cycle.

The first step in the conversion of amino acids into metabolic waste in the liver is removal of the alpha-amino nitrogen, which produces ammonia.
Because ammonia is toxic, it is excreted immediately by fish, converted into uric acid by birds, and converted into E927b Carbamide by mammals.

Ammonia (NH3) is a common byproduct of the metabolism of nitrogenous compounds.
Ammonia is smaller, more volatile, and more mobile than E927b Carbamide.

If allowed to accumulate, ammonia would raise the pH in cells to toxic levels.
Therefore, many organisms convert ammonia to E927b Carbamide, even though this synthesis has a net energy cost.
Being practically neutral and highly soluble in water, E927b Carbamide is a safe vehicle for the body to transport and excrete excess nitrogen.

E927b Carbamide is synthesized in the body of many organisms as part of the E927b Carbamide cycle, either from the oxidation of amino acids or from ammonia.
In this cycle, amino groups donated by ammonia and L-aspartate are converted to E927b Carbamide, while L-ornithine, citrulline, L-argininosuccinate, and L-arginine act as intermediates.

E927b Carbamide production occurs in the liver and is regulated by N-acetylglutamate.
E927b Carbamide is then dissolved into the blood (in the reference range of 2.5 to 6.7 mmol/L) and further transported and excreted by the kidney as a component of urine.

In addition, a small amount of E927b Carbamide is excreted (along with sodium chloride and water) in sweat.
In water, the amine groups undergo slow displacement by water molecules, producing ammonia, ammonium ions, and bicarbonate ions.
For this reason, old, stale urine has a stronger odor than fresh urine.

HUMANS, E927b CARBAMIDE:
The cycling of and excretion of E927b Carbamide by the kidneys is a vital part of mammalian metabolism.
Besides its role as carrier of waste nitrogen, E927b Carbamide also plays a role in the countercurrent exchange system of the nephrons, that allows for reabsorption of water and critical ions from the excreted urine.

E927b Carbamide is reabsorbed in the inner medullary collecting ducts of the nephrons, thus raising the osmolarity in the medullary interstitium surrounding the thin descending limb of the loop of Henle, which makes the water reabsorb.
By action of the E927b Carbamide transporter 2, some of this reabsorbed E927b Carbamide eventually flows back into the thin descending limb of the tubule, through the collecting ducts, and into the excreted urine.

The body uses this mechanism, which is controlled by the antidiuretic hormone, to create hyperosmotic urine — i.e., urine with a higher concentration of dissolved substances than the blood plasma.
This mechanism is important to prevent the loss of water, maintain blood pressure, and maintain a suitable concentration of sodium ions in the blood plasma.
The equivalent nitrogen content (in grams) of E927b Carbamide (in mmol) can be estimated by the conversion factor 0.028 g/mmol.

Furthermore, 1 gram of nitrogen is roughly equivalent to 6.25 grams of protein, and 1 gram of protein is roughly equivalent to 5 grams of muscle tissue.
In situations such as muscle wasting, 1 mmol of excessive E927b Carbamide in the urine (as measured by urine volume in litres multiplied by E927b Carbamide concentration in mmol/L) roughly corresponds to a muscle loss of 0.67 grams.

OTHER SPECIES of E927b CARBAMIDE:
In aquatic organisms the most common form of nitrogen waste is ammonia, whereas land-dwelling organisms convert the toxic ammonia to either E927b Carbamide or uric acid.

E927b Carbamide is found in the urine of mammals and amphibians, as well as some fish.
Birds and saurian reptiles have a different form of nitrogen metabolism that requires less water, and leads to nitrogen excretion in the form of uric acid.

Tadpoles excrete ammonia, but shift to E927b Carbamide production during metamorphosis.
Despite the generalization above, the E927b Carbamide pathway has been documented not only in mammals and amphibians, but in many other organisms as well, including birds, invertebrates, insects, plants, yeast, fungi, and even microorganisms.

HISTORY of E927b CARBAMIDE:
E927b Carbamide was first obtained by Herman Boerhaave in 1727 from evaporates of urine.
The discovery is also attributed to the French chemist Hilaire Rouelle as well as William Cruickshank.
In 1773, Hilaire Rouelle obtained crystals containing E927b Carbamide by evaporating human urine and treating the concentrate with alcohol.

This method was aided by Carl Wilhelm Scheele's discovery that crystals precipitated when urine was treated by concentrated nitric acid.
Uremic frost was first described in 1856 by the Austrian physician Anton Drasche.

Uremic frost has become rare since the advent of dialysis.
It is the classical pre-dialysis era description of crystallized E927b Carbamide deposits over the skin of patients with prolonged kidney failE927b Carbamidend severe uremia.

Historical preparation
Antoine François, comte de Fourcroy and Louis Nicolas Vauquelin discovered in 1799 that the nitrated crystals were identical to Rouelle's substance and invented the term "E927b Carbamide."
Berzelius further improved the purification of E927b Carbamide.

In 1817 William Prout determining the chemical composition.
In the evolved procedure, E927b Carbamide was precipitated as E927b Carbamide nitrate by adding strong nitric acid to urine.
To purify the resulting crystals, they were dissolved in boiling water with charcoal and filtered.
After cooling, pure crystals of E927b Carbamide nitrate form.

To reconstitute the E927b Carbamide from the nitrate, the crystals are dissolved in warm water, and barium carbonate added.
The water is then evaporated and anhydrous alcohol added to extract the E927b Carbamide.
This solution is drained off and evaporated, leaving pure E927b Carbamide

Wöhler's experiments
In 1828, the German chemist Friedrich Wöhler prepared E927b Carbamide by treating silver cyanate with ammonium chloride.
AgNCO + [NH4]Cl → CO(NH2)2 + AgCl

This was one of the first artificial syntheses of biological compounds from inorganic starting materials, without the involvement of living organisms.
The results of this experiment implicitly discredited vitalism, the theory that the chemicals of living organisms are fundamentally different from those of inanimate matter.

This insight was important for the development of organic chemistry.
His discovery prompted Wöhler to write triumphantly to Jöns Jakob Berzelius:
I must tell you that I can make E927b Carbamide without the use of kidneys, either man or dog.

Ammonium cyanate is E927b Carbamide.
His second sentence was incorrect.
Ammonium cyanate [NH4]+[OCN]− and E927b Carbamide CO(NH2)2 are two different chemicals with the same empirical formula CON2H4, which are in chemical equilibrium heavily favoring E927b Carbamide under standard conditions.

Laboratory preparation
E927b Carbamide can be produced by heating ammonium cyanate to 60 °C (140 °F).
[NH4]+[OCN]− → (NH2)2CO
Industrial production

In 2020, worldwide production capacity was approximately 180 million tonnes.
For use in industry, E927b Carbamide is produced from synthetic ammonia and carbon dioxide.
As large quantities of carbon dioxide are produced during the ammonia manufacturing process as a byproduct of burning hydrocarbons to generate heat (predominantly natural gas, and less often petroleum derivatives or coal), E927b Carbamide production plants are almost always located adjacent to the site where the ammonia is manufactured.

SYNTHESIS of E927b CARBAMIDE:
The basic process, patented in 1922, is called the Bosch–Meiser E927b Carbamide process after its discoverers Carl Bosch and Wilhelm Meiser.
The process consists of two main equilibrium reactions, with incomplete conversion of the reactants.
The first is carbamate formation: the fast exothermic reaction of liquid ammonia with gaseous carbon dioxide (CO2) at high temperatE927b Carbamidend pressure to form ammonium carbamate ([NH4]+[NH2COO]−):

2 NH3 + CO2 ⇌ NH4CO2NH2 (ΔH = −117 kJ/mol at 110 atm (11 MPa) and 160 °C (320 °F))
The second is E927b Carbamide conversion: the slower endothermic decomposition of ammonium carbamate into E927b Carbamide and water:
NH4CO2NH2 ⇌ CO(NH2)2 + H2O (ΔH = 15.5 kJ/mol at 160–180 °C (320–356 °F))
The overall conversion of NH3 and CO2 to E927b Carbamide is exothermic, with the reaction heat from the first reaction driving the second.

The conditions that favor E927b Carbamide formation (high temperature) have an unfavorable effect on the carbamate formation equilibrium.
The process conditions are a compromise: the ill-effect on the first reaction of the high temperature (around 190 °C (374 °F)) needed for the second is compensated for by conducting the process under high pressure (1.4–1.75 MPa (203–254 psi)), which favors the first reaction.

Although it is necessary to compress gaseous carbon dioxide to this pressure, E927b Carbamide is available from the ammonia production plant in liquid form, which can be pumped into the system much more economically.
To allow the slow E927b Carbamide formation reaction time to reach equilibrium, a large reaction space is needed, so the synthesis reactor in a large E927b Carbamide plant tends to be a massive pressure vessel.

Reactant recycling
Because the E927b Carbamide conversion is incomplete, the E927b Carbamide must be separated from the unconverted reactants, including the ammonium carbamate.
Various commercial E927b Carbamide processes are characterized by the conditions under which E927b Carbamide forms and the way that unconverted reactants are further processed.

Conventional recycle processes
In early "straight-through" E927b Carbamide plants, reactant recovery (the first step in recycling) was done by letting down the system pressure to atmospheric to let the carbamate decompose back to ammonia and carbon dioxide.

Originally, because it was not economic to recompress the ammonia and carbon dioxide for recycle, the ammonia at least would be used for the manufacture of other products such as ammonium nitrate or ammonium sulfate, and the carbon dioxide was usually wasted.
Later process schemes made recycling unused ammonia and carbon dioxide practical.
This was accomplished by the "total recycle process", developed in the 1940s to 1960s and now called the conventional recycle process.

It proceeds by depressurizing the reaction solution in stages (first to 1.8–2.5 MPa (260–360 psi) and then to 0.2–0.5 MPa (29–73 psi)) and passing it at each stage through a steam-heated carbamate decomposer, then recombining the resulting carbon dioxide and ammonia in a falling-film carbamate condenser and pumping the carbamate solution back into the E927b Carbamide reaction vessel.

Stripping recycle process
The conventional recycle process for recovering and reusing the reactants has largely been supplanted by a stripping process, developed in the early 1960s by Stamicarbon in The Netherlands, that operates at or near the full pressure of the reaction vessel.
It reduces the complexity of the multi-stage recycle scheme, and it reduces the amount of water recycled in the carbamate solution, which has an adverse effect on the equilibrium in the E927b
Carbamide conversion reaction and thus on overall plant efficiency.
Effectively all new E927b Carbamide plants use the stripper, and many total recycle E927b Carbamide plants have converted to a stripping process.

In the conventional recycle processes, carbamate decomposition is promoted by reducing the overall pressure, which reduces the partial pressure of both ammonia and carbon dioxide, allowing these gasses to be separated from the E927b Carbamide product solution.
The stripping process achieves a similar effect without lowering the overall pressure, by suppressing the partial pressure of just one of the reactants in order to promote carbamate decomposition.

Instead of feeding carbon dioxide gas directly to the E927b Carbamide synthesis reactor with the ammonia, as in the conventional process, the stripping process first routes the carbon dioxide through the stripper.
The stripper is a carbamate decomposer that provides a large amount of gas-liquid contact.

This flushes out free ammonia, reducing its partial pressure over the liquid surface and carrying it directly to a carbamate condenser (also under full system pressure).
From there, reconstituted ammonium carbamate liquor is passed to the E927b Carbamide production reactor.
That eliminates the medium-pressure stage of the conventional recycle process

SIDE REACTIONS of E927b CARBAMIDE:
The three main side reactions that produce impurities have in common that they decompose E927b Carbamide.
E927b Carbamide hydrolyzes back to ammonium carbamate in the hottest stages of the synthesis plant, especially in the stripper, so residence times in these stages are designed to be short.
Biuret is formed when two molecules of E927b Carbamide combine with the loss of a molecule of ammonia.
2 NH2CONH2 → NH2CONHCONH2 + NH3

Normally this reaction is suppressed in the synthesis reactor by maintaining an excess of ammonia, but after the stripper, it occurs until the temperature is reduced.
Biuret is undesirable in E927b Carbamide fertilizer because it is toxic to crop plants to varying degrees, but it is sometimes desirable as a nitrogen source when used in animal feed.
Isocyanic acid HNCO and ammonia NH3 results from the thermal decomposition of ammonium cyanate [NH4]+[OCN]−, which is in chemical equilibrium with E927b Carbamide:

CO(NH2)2 → [NH4]+[OCN]− → HNCO + NH3
This decomposition is at its worst when the E927b Carbamide solution is heated at low pressure, which happens when the solution is concentrated for prilling or granulation (see below).
The reaction products mostly volatilize into the overhead vapours, and recombine when these condense to form E927b Carbamide again, which contaminates the process condensate.

CORROSION of E927b CARBAMIDE:
Ammonium carbamate solutions are highly corrosive to metallic construction materials – even to resistant forms of stainless steel – especially in the hottest parts of the synthesis plant such as the stripper.
Historically, corrosion has been minimized (although not eliminated) by continuous injection of a small amount of oxygen (as air) into the plant to establish and maintain a passive oxide layer on exposed stainless steel surfaces.
Highly corrosion-resistant materials have been introduced to reduce the need for passivation oxygen, such as specialized duplex stainless steels in the 1990s, and zirconium or zirconium-clad titanium tubing in the 2000s.

Finishing
E927b Carbamide can be produced in solid forms (prills, granules, pellets or crystals) or as solutions.

Solid forms
For its main use as a fertilizer E927b Carbamide is mostly marketed in solid form, either as prills or granules.
Prills are solidified droplets, whose production predates satisfactory E927b Carbamide granulation processes.
Prills can be produced more cheaply than granules, but the limited size of prills (up to about 2.1 mm (0.083 in) in diameter), their low crushing strength, and the caking or crushing of prills during bulk storage and handling make them inferior to granules.

Granules are produced by accretion onto E927b Carbamide seed particles by spraying liquid E927b Carbamide in a succession of layers.
Formaldehyde is added during the production of both prills and granules in order to increase crushing strength and suppress caking.
Other shaping techniques such as pastillization (depositing uniform-sized liquid droplets onto a cooling conveyor belt) are also used.

Liquid forms
Solutions of E927b Carbamide and ammonium nitrate in water (UAN) are commonly used as a liquid fertilizer.
In admixture, the combined solubility of ammonium nitrate and E927b Carbamide is so much higher than that of either component alone that it gives a stable solution with a total nitrogen content (32%) approaching that of solid ammonium nitrate (33.5%), though not, of course, that of E927b Carbamide itself (46%).

PHYSICAL and CHEMICAL PROPERTIES of E927b CARBAMIDE:
Molecular weight : 60,06 g/mol
Appearance Form: powder
Color: white
Odor: odorless
Odor Threshold: Not applicable
pH: 7,5 - 9,5 at 480 g/l at 25 °C
Melting point/freezing point:
Melting point/range: 132 - 135 °C
Initial boiling point and boiling range: Decomposes below the boiling point.

Flash point: Not applicable
Evaporation rate: No data available
Flammability (solid, gas): No data available
Upper/lower flammability or explosive limits: No data available
Vapor pressure: < 0,1 hPa at 25 °C
Vapor density: No data available
Relative density: 1,33 at 20 °C
Water solubility: 624 g/l at 20 °C completely soluble:
Partition coefficient: n-octanol/water
log Pow: < -1,73 at 22 °C - Regulation (EC) No. 440/2008,

Autoignition temperature: > 134 °C
Decomposition temperature: No data available
Viscosity
Viscosity, kinematic: No data available
Viscosity, dynamic: No data available
Explosive properties: No data available
Oxidizing properties: No data available
Other safety information:
Dissociation constant: < 0,6

Molecular Weight: 94.07
Hydrogen Bond Donor Count: 4
Hydrogen Bond Acceptor Count: 3
Rotatable Bond Count: 0
Exact Mass: 94.03784206
Monoisotopic Mass: 94.03784206
Topological Polar Surface Area: 110 Å²
Heavy Atom Count: 6

Formal Charge: 0
Complexity: 29
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: 2
Compound Is Canonicalized: Yes

Formulated from analytical grade reagent.
Choice of two concentrations.
Reproducibility from lot to lot.
Exactly pre-weighted in pouches.
Dissolve and use in minutes.
Product Components
Chemicals: Analytical grade.
Format: Exactly pre-weighed powder.
Volume: 100 ml.
Shelf life:
Three years after production date.

Chemical Name: Carbamide
Common Name: Urea
Food Additive Code: E927b
INS Number: 927b
CAS Number: 57-13-6
EC Number: 200-315-5
Molecular Formula: CH4N2O
Alternative Formula: CO(NH2)2
Molecular Weight: 60.056 g/mol
Chemical Family: Organic amide
Appearance: White crystalline solid
Odor: Nearly odorless or slight ammonia odor

Taste: Slightly bitter or cooling taste
Physical State: Solid
Chemical Name: Carbamide
Common Name: Urea
Molecular Formula: CH4N2O
Alternative Formula: CO(NH2)2
Molecular Weight: 60.056 g/mol
CAS Number: 57-13-6
EC Number: 200-315-5
Appearance: White crystalline powder or granules

Odor: Odorless or faint ammonia-like odor
Taste: Slightly bitter
Physical State: Solid
Density: Approximately 1.32–1.34 g/cm³
Melting Point: Approximately 132–135°C
Boiling Point: Decomposes before boiling
Solubility in Water: Highly soluble
Solubility in Ethanol: Slightly soluble
Solubility in Ether: Practically insoluble

pH: Neutral to slightly alkaline in aqueous solution
Hygroscopicity: Hygroscopic
Thermal Stability: Stable under normal conditions
Decomposition Temperature: Above melting point with ammonia release
Flammability: Non-flammable under normal conditions
Explosive Properties: None under standard conditions
Oxidizing Properties: None
Viscosity: Not applicable for solid form
Vapor Pressure: Very low

Crystal Structure: Tetragonal crystalline structure
Chemical Reactivity: Low to moderate
Hydrogen Bonding Capacity: High
Shelf Stability: Good under dry storage conditions
Corrosiveness: Low
Moisture Retention: Excellent humectant properties
Compatibility: Compatible with many aqueous systems
Nitrogen Content: Approximately 46% nitrogen by weight
Biodegradability: Biodegradable
Toxicity: Low at regulated food-use levels

FIRST AID MEASURES of E927b CARBAMIDE:
-Description of first-aid measures
*If inhaled
After inhalation:
Fresh air.
*In case of skin contact:
Take off immediately all contaminated clothing.
Rinse skin withwater/ shower.
*In case of eye contact:
After eye contact:
Rinse out with plenty of water.
Remove contact lenses.
*If swallowed:
After swallowing:
Make victim drink water (two glasses at most).
Consult doctor if feeling unwell.
-Indication of any immediate medical attention and special treatment needed:
No data available

ACCIDENTAL RELEASE MEASURES of E927b CARBAMIDE:
-Environmental precautions:
Do not let product enter drains.
-Methods and materials for containment and cleaning up:
Cover drains.
Collect, bind, and pump off spills.
Take up dry.
Dispose of properly.
Clean up affected area.

FIRE FIGHTING MEASURES of E927b CARBAMIDE:
-Extinguishing media:
*Suitable extinguishing media:
Water
Foam
Carbon dioxide (CO2)
Dry powder
*Unsuitable extinguishing media:
For this substance/mixture no limitations of extinguishing agents are given.
-Further information:
Suppress (knock down) gases/vapors/mists with a water spray jet.
Prevent fire extinguishing water from contaminating surface water or the ground water system.

EXPOSURE CONTROLS/PERSONAL PROTECTION of E927b CARBAMIDE:
-Control parameters:
--Ingredients with workplace control parameters:
-Exposure controls:
--Personal protective equipment:
*Eye/face protection:
Use Safety glasses.
*Skin protection:
Full contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 480 min
Splash contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 480 min
-Control of environmental exposure:
Do not let product enter drains.

HANDLING and STORAGE of E927b CARBAMIDE:
-Conditions for safe storage, including any incompatibilities:
Storage conditions
Tightly closed.
Dry.

STABILITY and REACTIVITY of E927b CARBAMIDE:
-Chemical stability:
The product is chemically stable under standard ambient conditions (room temperature).
-Conditions to avoid:
no information available