#Phosphorus Pentoxide

[jacksonharolin]

Phosphorus Pentoxide Manufacturing Plant Project Report 2023 Edition

Phosphorus pentoxide, also known as phosphoric anhydride or diphosphorus pentoxide, is a white crystalline solid primarily used as a potent dehydrating agent in the chemical industry.

[fuckyeahmarxismleninism]

By Lallan Schoenstein

White phosphorus weapons are a part of the billions of dollars in U.S. munitions that flow to Israel every year.

Burning white phosphorus produces a hot, dense, white smoke consisting mainly of phosphorus pentoxide in aerosol form. The smoke is more dangerous in enclosed spaces. It sticks to various surfaces, including skin and clothes; the burning substance is difficult to extinguish. White phosphorus can cause deep burns down to the bones, and remnants of the substance in the tissues can ignite again after the initial treatment.

[circumlocutive]

What’s your favorite desiccant and why is it phosphorus pentoxide

I have never used phosphorus pentoxide 0:

I use sodium sulfate or magnesium sulfate for most synthesis workups that need drying, mag sulfate if it doesn't mind some acidity but sodium sulfate is ok I guess if not. Just need a lot of it and good stirring and time.

For like, storage, I have dry samples in a dessicator filled with drierite (with the indicator dye 💅) but I fucking hate opening the dessicator every time bc it's ALWAYS stuck

For drying solvents, obviously id rather buy small sure sealed containers that come anhydrous for single applications but that's dummy expensive. I've been microwaving or vacuum ovening 3A and 4A molecular sieves but I kinda hate the whole process of needing another day to dry the damn dessicants, + all our sieves are old and when I went to dry some DMF it turned my solvent brown 😭 I have no clue what it is. Also the sieves I added to our deuterated chloroform for NMR have added some kind of 1.5ppm impurity on all my H-NMR

[deliciousdreamcat]

Chemicalsupplier15821839875@proton.me

Dimethyl ether, carbon tetrachloride, sodium thiohydrate, pyridine, hydrogen bromide, barium hydroxide, barium sulfide, phenol, hydrochloric acid, dibromomethane, sodium hydroxide, n-butylene ether, 3-methylpyridine, bromoethane, aluminum trichloride solution, benzene, ethanethiol, octadecyl acetamide, acetonitrile, N N-diisopropylethylamine, hydrogen fluoride [anhydrous], potassium antimony tartrate, n-butylacetate, ethylene oxide, cyclohexane, potassium hydroxide, aluminum trichloride [anhydrous], 2-nitroanisole, 1, 2-dichloropropene, n-butanol, magnesium, O O ≤-diethylthiophosphoyl chloride, phenol solution, N-(phenylethyl-4-piperidine) propionamide citrate, ethyl acetate, 1,4-xylene, 2-aminopropane, isophthaloyl chloride, 2-chlorotoluene, cyclopentene, propionic acid, hydrofluoric acid, 2-butenaldehyde, 2-methylpentane, ethylamine, bromine, coal tar pitch, ethyl formate, ammonia solution [containing ammonia > 10%] 1-aminohydrin, 4-ethoxyphenylamine, diisopropylamine, sodium ethanolate, nitrifying asphalt, hydrazide hydrate [containing hydrazide ≤ 64%], dimethyl sulfate, acetic acid [content > 80%], acetaldehyde, 2-butylketone, aluminum borohydrate, phenylethanolnitrile, 2-chlorobenzoyl chloride, sodium hypochlorite solution [containing available chlorine > 5%], 2-aminophenol, chloroplatinic acid, barium chloride, tert-butylbenzene, tribromide, methyl sulfide, Diphosphate pentasulfide, diethylamine, chlorobenzene, n-butylbenzene, 1,3-xylene, hydrogen peroxide solution [content > 8%], terephthaloyl chloride, red phosphorus, tetramethyl ammonium hydroxide, methanol, propionaldehyde, 2-methoxyphenylamine, bleach powder, triethyl propropionate, 1-bromobutene, cyclohexanone, di-(tert-butylperoxy) phthalate [paste Content ≤ 52%], tetrahydrofuran, trichloroethylene, magnesium aluminum powder, formic acid, sodium ethanol ethanol solution, isopropyl ether, acetic acid solution [10% < content ≤ 80%], 2-methyl-1-propanol, diethyl carbonate, sodium aluminum hydroxide, 2-methylpyridine, n-butylamine, toluene, thiourea, magnesium alloy [flake, banded or striped Containing magnesium > 50%], methyl benzoate, hydrobromide, 4-methylpyridine, iodine monochloride, sodium sulfide, 3-bromo-1-propene, 2-propanol, potassium borohydroxide, triethylamine, ammonia, 4-nitro-2-aminophenol, 1, 2-epichlorohydrin, 1-propanol, cyclopentane chloride, n-propyl acetate, bromoacetic acid, zinc chloride solution, trichloromethane, 1-bromopropane, monoamine [anhydrous], perchloric anhydride acetic anhydride solution, 1-bromopropane Potassium hydroxide solution [content ≥ 30%], boric acid, sodium borohydrate, hydroacetic acid bromide solution, acrylic acid [stable], cyclopentane chloride, ammonium hydrogen sulfate, calcium hydroxide, 2-ethoxyaniline, dimethyl carbonate, sodium nitroso, monomethylamine solution, zinc chloride, hydrogen sulfide, trimethyl acetate, iodine trichloride, nitric acid, sodium hydroxide solution [content ≥ 30%], trimethyl orthoformate, hydrogen chloride [anhydrous], 4-methoxyaniline, sulfur, succinile, acetic anhydride, dipropylamine, methyl acetate, isopropylbenzene, propionyl chloride, ethyl formate, phosphorus pentoxide, formaldehyde solution, nitrogen trifluoride, acetone, ethanol [anhydrous], white phosphorus, 1, 2-xylene, 1, 3-dichloropropene, 1, 1, 1-dichloroethane, N N-diethylethanolamine, sulfuric acid, N, N-dimethyl formamide, methyl mercaptan, 4-chlorotoluene, 1, 2-dichloroethane, dichloromethane, succinyl chloride, 2, 3-dichloropropene, xylene isomer mixture, tartrate nicotine, cyclopentane, petroleum ether, bromocyclopentane Potassium perchlorate, potassium chlorate, aluminum powder, chromic acid, iron chloride, lead nitrate, magnesium powder, nickel chloride, nickel sulfate, perchloroethylene, phosphate, potassium dichromate, sodium dichromate, zinc nitrate

[polarpanda73]

Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formula H2SO4. It is a colorless, odorless and viscous liquid that is miscible with water.[6]

Pure sulfuric acid does not exist naturally on Earth due to its strong affinity to water vapor; it is hygroscopic and readily absorbs water vapor from the air.[6] Concentrated sulfuric acid is highly corrosive towards other materials, from rocks to metals, since it is an oxidant with powerful dehydrating properties. Phosphorus pentoxide is a notable exception in that it is not dehydrated by sulfuric acid, but to the contrary dehydrates sulfuric acid to sulfur trioxide. Upon addition of sulfuric acid to water, a considerable amount of heat is released; thus the reverse procedure of adding water to the acid should not be performed since the heat released may boil the solution, spraying droplets of hot acid during the process. Upon contact with body tissue, sulfuric acid can cause severe acidic chemical burns and even secondary thermal burns due to dehydration.[7][8] Dilute sulfuric acid is substantially less hazardous without the oxidative and dehydrating properties; however, it should still be handled with care for its acidity.

Sulfuric acid is a very important commodity chemical, and a nation's sulfuric acid production is a good indicator of its industrial strength.[9][non-primary source needed] It is widely produced with different methods, such as contact process, wet sulfuric acid process, lead chamber process and some other methods.[10] Sulfuric acid is also a key substance in the chemical industry. It is most commonly used in fertilizer manufacture,[11] but is also important in mineral processing, oil refining, wastewater processing, and chemical synthesis. It has a wide range of end applications including in domestic acidic drain cleaners,[12] as an electrolyte in lead-acid batteries, in dehydrating a compound, and in various cleaning agents. Sulfuric acid can be obtained by dissolving sulfur trioxide in water.

shitting

[er-cryptid]

Molecular Compound Names Examples

N3O5 = trinitrogen pentoxide

PCl6 = phosphorus hexachloride

S3F6 = trisulfur hexafluoride

N4O10 = tetranitrogen decoxide

N2S5 = dinitrogen pentasulfide

BCl3 = boron trichloride

Si4F9 = tetrasilicon nonafluoride

CI3 = carbon triiodide

P4O8 = tetraphosphorus octoxide

N2O5 = dinitrogen pentoxide

C3F5 = tricarbon pentafluoride

BCl4 = boron tetrachloride

[soapfcrce-a]

stay with me , okay ? - decker || @mvnces

There was a joke to be made about how that was easier said than done, but it was taking everything for him to just remain conscious. Assholes really had the nerve to jump him mid-disarming, hell he was probably lucky enough that the blast didn’t do more than make the ringing in his left ear worse for wear. 

Of course, Soap wasn’t aware of how much worse the rest of the injuries were and where the other wet spots were while he hung off of Decker’s back. For all he knew the fuzz in his head was the more concerning part. Keep talking, Johnny. 

“Balancing... chem shite’s easier than they think...” A burble, but he was at least talking. Unfortunately it was going to be dull but it was something for Soap to focus on. “L-Like... balancing phosphorous pentoxide with—mn, water... gets y’ phosphoric acid...” 

It’s a struggle, especially with the way Decker’s movement doesn’t agree with any part of Soap’s body that wasn’t already screaming for relief. “Formula--formula wise—write it out.. Gotta balance the phosphorus first--” 

[learnwithmearticles]

Phosphorus

The phosphorus cycle and the use of phosphorus.

Phosphorus in the Mountains, Land, and Water

Phosphorus is a naturally occurring element that cycles through living and non-living material.

A major reservoir of phosphorus is in rock, which can become exposed to weathering from movement of tectonic plates. When physical and chemical erosion occurs, pieces of phosphorus become parts of soils and water. Sedimentation follows as phosphorus mixes with organic matter. Then it can be taken up by living organisms.

Phosphorus is essential to all plants, and a major component of balanced soil for most annual plants. It is vital for growing roots and many parts like stems and fruits. When looking to garden, examining the necessary soil ratios of Phosphorus, Nitrogen, and Potassium is key to producing healthy plants.

The uptake of phosphorus into plants is how phosphorus enters the food chain. There, it is important to all animals, in which it is a major component of the skeletal system. It has been observed to affect growth and reproduction2. 

There are no major gaseous forms of phosphorus, so the cycle continues with waste and detritus returning phosphorus to soil. Sometimes from sediment and soil the phosphorus will re-enter rock formations, but otherwise will be taken back up into organic matter.

White phosphorus

White phosphorus is one of three physical molecular forms in which phosphorus can exist. It does not occur on its own but is manufactured from rock, mainly to create phosphoric acid. It can still be found in some current productions of rat poison3.

White phosphorus is very unstable in the air and often stored under water. It is also very toxic. When it first started being used by the military, it was ignited to hide tanks behind a smokescreen or to force opposing sides to move4. The smokescreen of ignited white phosphorus is phosphorus pentoxide. It reacts with moisture to form phosphoric acid which corrodes and burns, and does so to lungs, eyes, and throats. Repeated exposure can cause bronchitis and drying or cracking skin5. Additionally, this substance becomes more corrosive as the surrounding temperature rises.

Not only is the use of white phosphorus in attacks incredibly harmful, but even in tests or training, it can cause lasting damage. Water runoff carries debris including white phosphorus to waterways, and it can stay in water for hours or days, or even thousands of years in deeper soil deposits. If the water has a low oxygen concentration, the white phosphorus can react to form phosphine. Phosphine is also very toxic and enters the air quickly, though once in air changes into less harmful chemicals within a day3.

War Crimes

In 1923, the British Mandate for Palestine imposed British rule over the nation of Palestine. In the Palestinian land, Britain decided to establish a territory for Jewish people displaced by war. Of course, this immigration of Jewish people greatly increased during World War II and events leading up to it, as Britain forced Arab inhabitants to allow this despite their continued protests of it.

In 1948, the British Mandate ended, leaving the Palestinian Arab population and Jewish population in conflict that quickly included violence. This came with the partition of Palestine into Palestine and Israel. The ‘collective Palestine’ became largely fractured, with many in refugee camps or under Egyptian control in the Gaza strip until 1967.

The Arab-Israeli war in 1967 resulted in Israel control over the Gaza strip and the movement of Arab populations and, ultimately, the large Israeli Jewish population ruling over a much smaller Palestinian population6.

The following decades have been continually contentious and violent between opposing forces, and most recently a severe onslaught of attacks have come from the Israeli government towards Palestinian-inhabited regions. The targets of these attacks have included a heavy percentage of civilian centers of life, often with the unsubstantiated excuse that a valid military target was in the building - buildings such as hospitals and residential buildings. In 2023, more than 18,000 Palestinian civilians have died from these attacks, including 56 journalists and media workers7.

These attacks have included the use of white phosphorus bombs.

The non-governmental organization Human Rights Watch reported that Israel used white phosphorus bombs in Gaza and Lebanon in 2023, as well as having used them in Gaza in 2008-2009. In both situations, the use of these bombs included attacking heavily civilian-populated areas8.

While they are not banned, they are heavily restricted under international law. The use of them in urban areas or heavily populated areas is absolutely considered illegal. These weapons are highly incendiary and spread over large distances when ignited in the air. Reports of specific injuries caused by these bombs in Gaza are difficult to find, but they can cause severe burns, even down to the bone, respiratory issues, and long-term mental illness, scarring, and disabilities9.

Human Rights Watch has a detailed process of verifying that the evidence of white phosphorus use is true, that Israel has ignited white phosphorus over civilian areas9. No national leaders have made significant attempts to address this or prevent the continued genocide against Palestinians. A journalist working for the Washington Post found debris of these bombs in southern Lebanon, where it had injured nine people; The debris indicates that the bombs were produced in the United States10. While we do not know if the United States sent them to Israel to be used as incendiaries as opposed to smokescreens, they are only some of the billions of dollars in munitions that the United States sends to Israel.

A spokesperson for the U.S. National Security Council claimed that further investigation is being done and that, when providing weapons to another military, the United States of course expects them to be used within the law11. So, the public now has to hold the government responsible for instilling ramifications for Israel having ‘misused’ supplied weapons. Hopefully, when the government acknowledges these unlawful uses of white phosphorus, if they do, they explain how they will be changing their actions to reflect this. Continuing to supply weapons to an unlawful military is showing support for and cosigning their unlawful actions.

Humans have turned phosphorus into a substance useful in warfare, and have since restricted its use in warfare. However, recent conflicts have exposed the willingness of a recognized nation to disregard established laws and commit genocide. National government are responsible for keeping each other in check and should not be allowing this to continue.

Unfortunately, much of this is a farce. The niceties and benefit of the doubt are unwarranted after what nations have allowed and, in the case of the United States, silently endorsed. Residential areas are being attacked, children are being shot. Israel is trying to terminate all Palestinians. What more can we say when this news is not enough to cause action?

Additional Resources

1.https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/phosphorus-cycle#:~:text=The%20global%20phosphorus%20cycle%20has,riverine%20transport%20of%20phosphorus%20to

2. https://www.annualreviews.org/doi/pdf/10.1146/annurev-arplant-102720-125738

3.https://wwwn.cdc.gov/tsp/PHS/PHS.aspx?phsid=286&toxid=52#:~:text=Because%20of%20its%20high%20reactivity,phosphoric%20acid%20and%20other%20chemicals

4.https://www.theguardian.com/science/2005/nov/19/thisweekssciencequestions.uknews#:~:text=White%20phosphorus%20was%20discovered%20300,burn%20the%20residue%20that%20formed

5. https://www.nj.gov/health/eoh/rtkweb/documents/fs/1516.pdf

6. https://www.britannica.com/place/Palestine/Resurgence-of-Palestinian-identity

7. https://cpj.org/2023/12/journalist-casualties-in-the-israel-gaza-conflict/

8.https://www.aljazeera.com/news/2023/10/13/what-is-the-white-phosphorus-that-israel-is-accused-of-using-on-gaza

9. https://time.com/6323482/israel-white-phosphorus-gaza-lebanon/

10.https://www.washingtonpost.com/investigations/2023/12/11/israel-us-white-phosphorus-lebanon/11.https://www.nytimes.com/2023/12/11/world/middleeast/israel-white-phosphorus-us.html

[zzhuaiqngmachine]

Organic fertilizer equipment of chicken manure organic fertilizer production line

The construction cycle of organic fertilizer equipment project is short, the market risk is small (organic fertilizer generally has a shelf life of at least 5 years), the recovery period is short (oversupply in busy farming), and the market potential is large (China's land and resources are rich, especially in Henan, Northeast and other agricultural provinces, and the consumption is quite large). Under normal circumstances, the investment can be recovered in one year and the profit can be generated in the current year. Organic fertilizer production lines generally include: raw material selection (chicken manure, etc.) → drying and sterilization → mixing of ingredients → granulation → cooling and screening → metering and sealing → storage of finished products. The more complex organic manure production process is: Organic fertilizer raw materials (livestock and poultry manure, domestic waste, dead leaves, biogas residue, waste bacteria, etc.) after turning the pile machine fermentation by half-wet material crusher, then add nitrogen, phosphorus, adding potassium and other elements (pure nitrogen, phosphorus pentoxide, potassium chloride, ammonium chloride, etc.), so that the mineral elements meet the requirements of the standard, stirred with a blender, into the granulator, dried out, screened with a screening machine, Packaging of qualified products, unqualified products returned to granulator granulation. The equipment configuration and construction scale of chicken manure organic fertilizer production line is generally 30,000-100,000 tons/year. Local resources, market capacity and market coverage should be considered comprehensively. First, the scale of investment and product design should be based on the characteristics of raw material resources, local soil conditions, local planting structure and main crop varieties, plant site conditions, production automation and other conditions, if you have special requirements, you can call us directly, we will provide equipment according to your requirements.

[jacksonharolin]

Phosphoric Anhydride Manufacturing Plant Project Report 2023 Edition

Phosphoric anhydride, more commonly referred to as phosphorus pentoxide or diphosphorus pentoxide, is a potent dehydrating agent known for its unique chemical properties.

[wysiwyggins]

Chart 3-9873c : Phosphorus pentoxide ventilators and quality control area

[thesammathew]

Poly Phosphoric Acid Has a Great Importance in Industrial Applications:

Summary: Poly Phosphoric acid is produced by mixing water and adding polymerizing to the technical or dietary phase of phosphoric acid, for example, in a complete column or by absorbing P 2O 5 vapor from re-dispersing phosphoric acid. Polyphosphoric acid is used in a variety of applications, including the production of petroleum products, surfactants, lotions and shampoos, oil extraction chemicals, industrial water treatment chemicals, flame structures, large fibers and pigs, such as quinacridone pigments, and additives. improved performance of petroleum products. Other industrial uses of polyphosphoric acid produce phosphoric acid products containing impurities, such as phosphate esters, other organic compounds and metals.

Introduction:

Poly phosphoric acid is used in a variety of applications, including the production of petroleum products, surfactants, lotions and shampoos, oil extraction chemicals, industrial water treatment chemicals, flame structures, large fibers and pigs, such as quinacridone pigments, and additives. improved performance of petroleum products. Other industrial uses of polyphosphoric acid produce phosphoric acid products containing impurities, such as phosphate esters, other organic compounds and metals. Phosphoric acids can also be produced by other industrial processes, for example, polycarbonate self-production processes, synthetic fibers, pharmaceutical and chemical compounds in agriculture, and other industrial processes using phosphorus-containing substances. These phosphoric acid products can be reduced and disposed of as waste. Like Rostabil TTDP or tri decyl Phosphite is an industrial chemical. It is a clear liquid that contains C39H81O3P as a chemical formula. It is a test kyl phosphate used as a solvent only in ABS, PET, fiber fibers, lubricants, PVC, polycarbonate and polyurethanes.

Poly Phosphoric acid, molecular formula: H6P4O13, is a composite of inorganic chemicals, with strong hygroscopic properties. Polyphosphoric Acid is a liquid, colorless, and viscous liquid compound. Polyphosphoric acid is a combination of direct phosphoric acid and orthophosphoric acid. Polyphosphoric acid is formed by heat and body temperature of phosphoric acid followed by the polycondensation process. During this process, phosphoric acid forms chains and removes water molecules. Also, Polyphosphoric acid can be produced by adding phosphorus pentoxide to water and heating it and mixing the mixture to produce a finishing product. Polyphosphoric Acid appears as a glass at low temperatures and becomes a liquid / liquid when heated to 50 to 60 ° C. Poly Phosphoric acid absorbs, is water resistant and is hydrolyzed into phosphoric acid. In the field, Polyphosphoric Acid is widely used as reagents in the synthesis of amide acids, acetylation, circulating ketones and olefins, alkylation, and amines, among others. Also, Polyphosphoric Acid is found in the application as a stimulant in fuel and fuel financing, polymerization, condensing, alkylation, and isomerization processes. Polyphosphoric acid is odorless, viscosity liquid with strong hygroscopic properties. Phosphoric acids contain <95% H3PO4 (68% P2O5) containing simple orthophosphoric acid. In the above components the acid contains a combination of ortho, pyro, tri, tetra and highly concentrated phosphoric acid. For this reason acids with concentration> 68% P2O5 are better known as polyphosphoric acid. Polyphosphoric acid does not dissolve in water, hydrolysing into orthophosphoric acid by heat production. They are insoluble in hydrocarbons and halogenated hydrocarbons.

Conclusion:

Poly Phosphoric acid can be used as a cyclisation / ring reagent in reaction such as acetylation, alkylation, amine production, amide acid, circulating ketones, cyclic olefins or oxygen

[yes-lazystudentconnoisseur-fan]

Insight of Phosphorus Pentoxide and its Applications

Phosphorus Pentoxide is used as a strong drying and dehydrating agent such as the dehydration of amides to nitriles. It is also used to manufacture optical glass, heat-insulating glass, pesticides and in the pharmaceutical industry.

It is a chemical compound with formula P2O5. As we know the white crystalline solid is the an anhydride of phosphoric acid. It is a powerful desiccant. This is a white, flammable, dangerous, and extremely deliquescent solid. While the solid reacts with water very violently to produce the phosphoric acid. It has been prepared by various phosphorus reactions with excess oxygen. The crude is then purified by sublimation. As we know that phosphorus pentoxide is very much stable, but reacts violently with water, alcohol, metals, sodium, potassium, ammonia, oxidizing agents, HF, peroxides, magnesium, and very much stronger bases.

Uses of phosphorus pentoxide — Phosphorus pentoxide is usual material and reagent in chemical industry, this product is widely used in the industries of medicine, coating auxiliaries, printing and dyeing auxiliaries, anti static additive, titanate coupling agent, phosphorus oxychloride

It is very much used as a strong dehydrating agent, which is very much capable even of dehydrating concentrated sulphuric acid into sulphur trioxide.

It dehydrates amides to nitriles.

In manufacturing of phosphorus compounds.

Used in purifying sugar.

Optical glass making.

Heat-insulating glass.

It is very much used as a drying agent for materials with which it does not react

Medicine, pesticide and surfactant manufacturing.

Phosphorus along with calcium is an essential element in plant and animal growth, thus its principal source is organic ash (i.e. calcined cattle bones).

Phosphoric oxide is normally present in only trace amounts in ceramic materials.

It can act as a melter in middle to high fire, but its power-per-unit-added drops drastically beyond 5% additions.

Small amounts can produce colloidal opacity as in Chinese chun glazes. The depth of Sung glazes is attributed to phosphorus.

P2O5 is a glass network former like boric oxide and silicon dioxide. Phosphoric glass tends to show as a bluish flush in glazes. It does not enter the silica chain in the matrix. However, P2O5 by itself (with no SiO2 present in the matrix) is a glass former and the base of an entire class of glasses that can be doped with rare earths and metals for produce special purposes ranging from soluble medical implants to insoluble acid-resistance and even radiation resistance.

Phosphorus can vitrify porcelains without softening and is the key to translucency in bone china.

Phosphate ions are added to glaze frits as a color control agent during the melting of titania opacified frits.

P2O5 itself can crystallize in multiple forms. It is known to influence the rate of nucleation and/or crystallization in Li2O and MgO low expansion glaze systems.

P2O5 combines with certain oxides of iron forms colorless compounds. This suggests that P2O5 could be used to allow the use of less pure materials in glazes and glass.

Conclsuion-Phosphorite mineral Ca3(PO4)2 and Apatite 3Ca3(PO4)2 Ca(Cl,F)2 are the parent rocks of phosphate fertilizers. The latter can thus be used to introduce phosphorus into glazes and frits.

[materialsscienceandengineering]

Glasses: Phosphate glasses

A category of glass based on phosphorus pentoxide (P2O5), phosphate glasses are formed with a structure of phosphorus tetrahedra linked by bridging oxygens - as shown in the bottom image above. These tetrahedra are classified using Qt terminology, where t is the number of bridging oxygens per tetrahedra. (Q0 is an individual orthophosphate anion, while Q3 is a phosphate tetrahedron with three bridging oxygens connecting it to the rest of the glass structure). 

This network of tetrahedra is easily interrupted, meaning that, in general, phosphate glasses have very low glass transformation temperatures (meaning they can be formed at lower temperatures). The structure of the phosphorus pentoxide used to create the glass (of which the crystalline form has several polymorphs) also has an effect on the structure of the glass, and thus its properties. Glasses produced with short melting times retain some of the structural details of the crystalline forms, though longer melting times allow the properties to converge toward equilibrium values. Phosphate glasses are also typically softer than the more common silicate glasses, with poor chemical durability, high thermal expansion coefficients, and the added bonus of being biocompatible.

Just as with other glasses, elements added to phosphate glasses can alter properties in favorable ways. The addition of alkali and alkaline earth oxides break the structural rings and convert the glass network to linear chains of phosphorus-oxygen tetrahedra - if these chains are oriented during fiber drawing, phosphate glasses with directional properties can be produced, resembling organic polymeric glasses. Replacing some of the oxygen with nitrogen in phosphate glasses can both improve the chemical durability and increase the glass transformation temperature.

Phosphate glass is often used as laser gain media, thanks to its high solubility for rare earth ions such as erbium, ytterbium, and neodymium, and is being considered as a possible waste matrix to immobilize high level nuclear wastes, thanks to its higher waste loading capacity and lower processing temperatures. Phosphate glasses can also be mixed with other types of glass, yielding glasses such as fluorophosphate, phosphosilicate, and aluminophosphate glasses. Other applications of phosphate glasses include fast ion conductors, glass-to-metal seals, and biomedical engineering. 

Sources: ( 1 ) ( 2 - top middle image ) ( 3 ) ( 4 ) ( 5 )

Image sources: (Top left) (Top right) (Bottom)