Phosphorus-based industry

The only major bulk chemical not so far considered is phosphoric acid, which can be manufactured pure from phosphorus and in an impure form from phosphate rock. The latter process is the dominant one, the impure product being used mainly in the preparation of fertilizers. Phosphate rock is also the most common source of elemental phosphorus. It is extracted by open-cast mining. The thermal process for producing phosphoric acid from the element produces an acid which is about three times more expensive than that produced direct from phosphate rock using the so-called wet process. 

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The early patent disclosures have claimed the application of a wide spectrum of gas-evolving ingredients and phosphorus-based organic molecules as flame retarding additives in the electrolytes. Pyrocarbonates and phosphate esters were typical examples of such compounds. The former have a strong tendency to release CO2, which hopefully could serve as both flame suppressant and SEI formation additive, while the latter represent the major candidates that have been well-known to the polymer material and fireproofing industries.The electrochemical properties of these flame retardants in lithium ion environments were not described in these disclosures, but a close correlation was established between the low flammability and low reactivity toward metallic lithium electrodes for some of these compounds. Further research published later confirmed that any reduction of flammability almost always leads to an improvement in thermal stability on a graphitic anode or metal oxide cathode. 

The P-H bond is also weak enough to serve in thione-based radical chemistry. The first success was achieved with dialkyl phosphites [40a]. However, hypophosphorous acid and its salts proved to be even better [40b]. In a final paper [40c], the various phosphorus-based reagents were compared. The crystalline salt N-ethylpiperidine hypophosphite was very convenient and has been commercialized 140c]. The use of hypophosphorous acid has the advantages of nontoxicity, cheapness, and ease of removal from the organic reduction products. It already has several industrial applications. 

Sulphur/nitrogen and sulphur/phosphorus compounds Other multifunctional sulphur/nitrogen, sulphur/phosphorus-based additives have antioxidant and antiwear properties. These additives react with peroxy radicals and hydroperoxides, thus stabilising industrial lubricants and engine oils. Syntheses and generalised chemical structures are as in Reactions (4.67. 69) [64, 72, 73] ... 

Transition metal catalyzed olefin hydroformylation is an industrially important process for the production of oxygenated products.(l) Rhodiiun-catalyzed processes that enqjloy phosphorus-based ligands allow increased control of rate and regioselectivity when compared to cobalt-catalyzed processes. The first generation of rhodium catalysts was based on triarylphosphine ligands. Second genera-... 

Organophosphorus compounds (OPs) are utilized on a large scale as flame retarding agents and plasticizers in a variety of products, such as plastic materials, rubbers, varnishes, lubricants, hydraulic fluids, and other industrial applications. This family of chemicals consists of alkylated and arylated phosphate or phosphonate esters and related compounds such as phosphites, phosphines, and related dimeric forms as well as ionic forms (Figure 31.2). " The low volatility of phosphoric acid and derivatives makes it the preferred choice of the phosphorus based FRs. These FRs are most effective in polymers that char readily. Also halogenated phosphate esters, such as tris(l-chloroisopropyl) phosphate (TCPP), and tris(2-chloroethyl) phosphate (TCEP), are widely used. These combine the properties of both the halogen and the phosphorus compounds. 

Antiblaze 1045 Flame Retardant is a unique phosphorus based product Intended for the plastics industry. Both thermoplastic and thersioset applications with demanding performance requirements can benefit from the use of this additive product. The balance of properties which characterize Antiblaze 1045 Flame Retaurdant are unique. 

Liao, S.H., Liu, P.L., Hsiao, M.C., Teng, C.C., Wang, C.A., Ger, M.D., Chiang, C.L., 2012. One-step reduction and functionalization of graphene oxide with phosphorus-based compound to produce flame-retardant epoxy nanocomposite. Industrial Engineering... 

While many industrial wastes are so low in nitrogen and phosphorus that these must be added if biologically based treatment is to be used, others contain very high levels ofthese nutrients. For example, paint-production wastes are high in nitrogen, and detergent production wastes are high in phosphorus. Treatment for removal of these nutrients is required in areas where eutrophication is a problem. 

The ability to efficiently synthesize enantiomerically enriched materials is of key importance to the pharmaceutical, flavor and fragrance, animal health, agrochemicals, and functional materials industries [1]. An enantiomeric catalytic approach potentially offers a cost-effective and environmentally responsible solution, and the assessment of chiral technologies applied to date shows enantioselective hydrogenation to be one of the most industrially applicable [2]. This is not least due to the ability to systematically modify chiral ligands, within an appropriate catalyst system, to obtain the desired reactivity and selectivity. With respect to this, phosphorus(III)-based ligands have proven to be the most effective. 

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