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Phosphoric acid phosphorus pentoxide

In the various preparations, ammonium heptamolybdate, cobalt nitrate, or nickel nitrate are preferred. The preferred phosphorus-containing precursors are phosphorus pentoxide, phosphoric acid, or their anion derivatives such as ammonium dihydrogen phosphate (NH4H2PO4) be-... [Pg.438]

Phosphorylation O-Benzyl phosphorus 0,0-diphenylphosphoric anhydride. 2-Cyanomethyl phosphate. Dibromomalonamide. Di-p-nilrobenzylphosphoryl chloridate. Dioxane diphosphate. Diphenylphosphorochloridate. Ethoxyacetylene. Metaphosphoric acid. o-Phenyl-ene phosphorochloridate. Phosphoric acid, anhydrous. Phosphorodimorpholidic chloride. Phosphorus pentoxide-Phosphoric acid. Phosphoryl chloride. Polyphosphoric acid. Pyro-phosphoryl tetrachloride. Silver dibenzyl phosphate. Silver diphenyl phosphate. Tetra-p-nitrophenyl pyrophosphate. [Pg.660]

Phosphorus pentoxide-<-Amine [1, 872, before Phosphorus pentoxide-Phosphoric acid]. Scheibler et al.1 used P205 in combination with quinoline for dehydration of the acid-sensitive diethoxyacetamide. McElvain and Clarke2 were unable to repeat... [Pg.441]

Phosphorus oxide chloride phosphorus pentoxide phosphoric acid... [Pg.240]

Polypeptides (s. a. Tripeptides) —, 1-step synthesis 18, 436 Polyphenyls, synthesis 16, 977 Polyphosphoric acid (s. a. Phosphorus pentoxide/ phosphoric acid) GG"f>0 ... [Pg.348]

Phosphorus pentoxide phosphoric acid (s. a. H(PO H) OH) Ring closure with acetals Thianaphthenes s. 17, 939... [Pg.650]

Phosphoric acid-nitric acid - 647, 738 Phosphoric acid pickling solution - 696 Phosphoric acid scrap liquor - 44, 45 Phosphoric acid slurry - 697 Phosphoric acid-sulfuric acid - 697, 725 Phosphoric acid, wet process - 697, 698 Phosphoric anhydride (see Phosphorus pentoxide) Phosphorous acid - 42, 43, 237, 245, 386, 390, 554,661,795... [Pg.946]

Phenyl isothiocyanate has been prepared from thiocarbanilide by the action of phosphorus pentoxide, hydrochloric acid, iodine, phosphoric acid, acetic anhydride, and nitrous acid. It has also been prepared from ammonium phenyl dithiocarbamate by the action of ethyl chlorocarbonate, copper sulfate lead carbonate, lead nitrate, ferrous sulfate,and zinc sulfate. ... [Pg.73]

Phosphorus compounds (phosphoric acid, phosphorous pentoxide, phosphorous oxychloride, phosphorous pentachloride, phosphorous pentasulphide)... [Pg.585]

The phosphate manufacturing and phosphate fertilizer industry includes the production of elemental phosphorus, various phosphorus-derived chemicals, phosphate fertilizer chemicals, and other nonfertilizer phosphate chemicals [1-30], Chemicals that are derived from phosphorus include phosphoric acid (dry process), phosphorus pentoxide, phosphorus penta-sulfide, phosphoms trichloride, phosphorus oxychloride, sodium tripolyphosphate, and calcium phosphates [8]. The nonfertilizer phosphate production part of the industry includes defluori-nated phosphate rock, defluorinated phosphoric acid, and sodium phosphate salts. The phosphate fertilizer segment of the industry produces the primary phosphorus nutrient source for the agricultural industry and for other applications of chemical fertilization. Many of these fertilizer products are toxic to aquatic life at certain levels of concentration, and many are also hazardous to human life and health when contact is made in a concentrated form. [Pg.399]

Phosphorus Pentoxide (Phosphoric anhydride. Phosphoric oxide. Diphosphorus pentoxide). P20s,mw 141.96 a soft, white powder absorbs moisture from the air with avidity, forming meta-, para-, or orthophosphoric acid, depending upon amt of w absorbed and upon conditions of absorption mp 580-585°, bp subl at 300°, d... [Pg.734]

Cyclodehydration 1,5-Diazabicyclo[4.3.0]nonene-5. 2,3-Dichloro-5,6-dicyano-l, 4-benzo-quinone. l,l-Dichloro-2,2-difluororoethyIene. Dichloroketene. Hydrobromic acid. Phos-phoryl chloride-Phosphoric acid-Phosphorus pentoxide. Polyphosphoric acid. Thionyl chloride. [Pg.513]

Phosphorus pentoxid—Phosphoric anhydride Phosphoric oxid —PaOj—142—is formed when P is burned in an excess of dry O. It is a white, flooculent solid, which has almost as great a tendency to combine with HjO as has P2O3. It absorbs moisture rapidly, deliquescing to a highly acid liquid, containing, not phosphoric, but metaphosphoric acid. It is used as a drying agent. [Pg.118]

A portion of the phosphorus currently produced in the United States is consumed to make compounds such as phosphorus pentoxide, phosphoric trichloride, and phosphorus penta-sulfide, which find use for the preparation of drying agents, plasticizers, oil additives, fire retardants, and insecticides. Most of the phosphorus, however, is converted into orthophosphoric acid, some of which is used in soft drinks, candy, baked goods, and various other food products. Furnace-grade acid finds wide use in metal-treating methods. [Pg.354]

Dehydration of the corresponding acid amides. This process usually requires phosphorus pentoxide (correctly termed phosphoric anhydride) as a dehydrating agent. [Pg.121]

The crude acetonitrile contains as impurity chiefly acetic acid, arising from the action of phosphoric acid on the acetamide. Therefore add to the nitrile about half its volume of water, and then add powdered dry potassium carbonate until the well-shaken mixture is saturated. The potassium carbonate neutralises any acetic acid present, and at the same time salts out the otherwise water-soluble nitrile as a separate upper layer. Allow to stand for 20 minutes with further occasional shaking. Now decant the mixed liquids into a separating-funnel, run off the lower carbonate layer as completely as possible, and then pour off the acetonitrile into a 25 ml, distilling-flask into which about 3-4 g. of phosphorus pentoxide have been placed immediately before. Fit a thermometer and water-condenser to the flask and distil the acetonitrile slowly, collecting the fraction of b.p. 79-82°. Yield 9 5 g. (12 ml.). [Pg.122]

Phosphorus(III) Oxide. Phosphoms(III) oxide [12440-00-5] the anhydride of phosphonic acid, is formed along with by-products such as phosphoms pentoxide and red phosphoms when phosphoms is burned with less than stoichiometric amounts of oxygen (62). Phosphoms(III) oxide is a poisonous, white, wax-like, crystalline material, which has a melting point of 23.8°C and a boiling point of 175.3°C. When added to hot water, phosphoms(III) oxide reacts violentiy and forms phosphine, phosphoric acid, and red phosphoms. Even in cold water, disproportionation maybe observed if the oxide is not well agitated, resulting in the formation of phosphoric acid and yellow or orange poorly defined polymeric lower oxides of phosphoms (LOOP). [Pg.373]

A third screening smoke-type is white phosphoms [7723-14-0] (WP), P (see Phosphorus and THE phosphides), which reacts spontaneously with air and water vapor to produce a dense cloud of phosphoms pentoxide [1314-56-3]. An effective screen is obtained as the P2O5 hydrolyzes to form droplets of dilute phosphoric acid aerosol. WP produces smoke in great quantity, but it has certain disadvantages. Because WP has such a high heat of combustion, the smoke it produces from bulk-filled munitions has a tendency to rise in pillarlike mass. This behavior too often nullifies the screening effect, particularly in stiU air. Also, WP is very brittle, and the exploding munitions in which it is used break it into very small particles that bum rapidly. [Pg.401]

Phosphorus Pentoxide. This compound, P2O55 (Class 1, nonregenerative) is made by burning phosphoms ia dry air. It removes water first by adsorptioa, followed by the formation of several forms of phosphoric acid (2). Phosphoms peatoxide [1314-56-3] has a high vapor pressure and should only be used below 100°C. Its main drawback is that as moisture is taken up, the surface of the granules becomes wetted and further moisture removal is impeded. For this reason, phosphoms pentoxide is sometimes mixed with an iaert material (see Phosphoric acids and phosphates). [Pg.507]

Phosphoric acid made by the wet process, in which phosphate rock is treated with sulfuric acid, is highly inert toward lead in any concentration for temperatures up to 150°C, However, in the dry process, where hydrogen phosphate (H3PO4) is made directly from phosphorus or phosphorus pentoxide (P2OS), a chemical reaction with lead occurs. [Pg.86]

Phosphorsaure, /. phosphoric acid, -anhydrid, n. phosphoric anhydride (phosphorus pentoxide). -losimg, /. phosphoric acid solution, -salz, n. phosphate. [Pg.340]

Surfactants are prepared which contain carboxylic acid ester or amide chains and terminal acid groups selected from phosphoric acid, carboxymethyl, sulfuric acid, sulfonic acid, and phosphonic acid. These surfactants can be obtained by reaction of phosphoric acid or phosphorus pentoxide with polyhydroxystearic acid or polycaprolactone at 180-190°C under an inert gas. They are useful as polymerization catalysts and as dispersing agents for fuel, diesel, and paraffin oils [69]. [Pg.565]

A mixture of monolauryl phosphate sodium salt and triethylamine in H20 was treated with glycidol at 80°C for 8 h to give 98% lauryl 2,3-dihydro-xypropyl phosphate sodium salt [304]. Dyeing aids for polyester fibers exist of triethanolamine salts of ethoxylated phenol-styrene adduct phosphate esters [294], Fatty ethanolamide phosphate surfactant are obtained from the reaction of fatty alcohols and fatty ethanolamides with phosphorus pentoxide and neutralization of the product [295]. A double bond in the alkyl group of phosphoric acid esters alter the properties of the molecule. Diethylethanolamine salt of oleyl phosphate is effectively used as a dispersant for antimony oxide in a mixture of xylene-type solvent and water. The composition is useful as an additive for preventing functional deterioration of fluid catalytic cracking catalysts for heavy petroleum fractions. When it was allowed to stand at room temperature for 1 month it shows almost no precipitation [241]. [Pg.615]

Poly(phosphoric acid) was prepared by adding a 1.52/1 weight ratio of phosphorus pentoxide to 85% phosphoric acid in ice bath and then heating at 150°C for 6 hours, with stirring under nitrogen atmosphere. [Pg.267]

Phosphorus pentoxide reacts with moisture in the air to form phosphoric acid. WP munitions were used by U.S. military forces and their allies to mark targets and to provide smoke screen coverage for troops and equipment in combat zones. These munitions were produced primarily by the dip-fill or wet-fill method illustrated by Figure 1. The method is called dip-fill because empty munition bodies are dipped below the molten phosphorus level in an open tank until the munitions are filled with liquid phosphorus. The method is also called wet-fill because a water overlay is maintained over the liquid phosphorus (in the fill tank) to prevent spontaneous combustion of the chemical element and because the filled munition will have a slight water overlay (up to 1/8" column height allowed). [Pg.168]

A. Trifluoromethanesulfonic Anhydride. To a dry, 100-ml., round-bottomed flask are added 36.3 g. (0.242 mole) of trifluoromethane-sulfonic acid (Note 1) and 27.3 g. (0.192 mole) of phosphorus pentoxide (Note 2). The flask is stoppered and allowed to stand at room temperature for at least 3 hours. During this period the reaction changes from a slurry to a solid mass. The flask is fitted with a short-path distilling head and then heated first with a stream of hot air from a heat gun and then with the flame from a small burner. The flask is heated until no more trifluoromethanesulfonic anhydride distills, b.p. 82-115°. The yield of the anhydride, a colorless liquid, is 28.4-31.2 g. (83-91%). Although this product is sufficiently pure for use in the next step of this preparation, the remaining acid may be removed from the anhydride by the following procedure. A slurry of 3.2 g. of phosphorous pentoxide in 31.2 g. of the crude anhydride is stirred at room temperature in a stoppered flask for 18 hours. After the reaction" flask has been fitted with a short-path distilling head, it is heated with an oil bath to distill iD.7 g. of forerun, b.p. 74—81°, followed by 27.9 g. of the pure trifluoromethanesulfonic acid anhydride, b.p. 81-84° (Note 3). [Pg.110]

Af-Ethyl-A-(3-halo-2-methylphenyl)aminomethylenemalonates (106, R = Et, R1 = Me, R2 = Hlg, R3 = H) were heated in polyphosphoric acid, prepared from phosphoric acid and phosphorus pentoxide, at 140°C for 40 min. The reaction mixture was then poured into water, and the product was hydrolyzed with 10% aqueous sodium hydroxide to give quinoline-3-carboxylic acids (696, R = Et, R1 = Me,R2 = Hlg) in 68-70% yields (80GEP3007006). [Pg.164]

Nakagome and co-workers effected the successful cyclization of N-ethyl-N-arylaminomethylenemalonates (749) in poly phosphoric acid, prepared from orthophosphoric acid and phosphorus pentoxide in polyphosphate ester (PPE), prepared from phosphorus pentoxide and anhydrous diethyl ether in chloroform in phosphoryl chloride on the action of boron trifluoride etherate on the action of acetic anhydride and concentrated sulfuric acid or on the action of phosphorus pentoxide in benzene [71GEP2033971, 71JHC357 76JAP(K) 18440]. Depending on the work-up process, l-ethyl-4-oxoquinoline-3-carboxylates (750, R1 = Et), l-ethyl-4-oxoquinoline-3-carboxylic acids (750, R2 = H) and 3-ethoxycarbonyl-4-chloroquinolinium iodides (751) were obtained. Only the cyclization of... [Pg.173]


See other pages where Phosphoric acid phosphorus pentoxide is mentioned: [Pg.1388]    [Pg.489]    [Pg.463]    [Pg.1388]    [Pg.489]    [Pg.463]    [Pg.1095]    [Pg.573]    [Pg.309]    [Pg.869]    [Pg.27]    [Pg.62]    [Pg.68]    [Pg.869]    [Pg.160]    [Pg.1264]    [Pg.1357]    [Pg.442]   
See also in sourсe #XX -- [ Pg.872 ]




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Pentoxides

Phosphoric acid pentoxide

Phosphoric phosphorus pentoxide

Phosphorous pentoxide

Phosphorus pentoxid

Phosphorus pentoxide

Phosphorus phosphoric acid

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