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Phosphoms sulfide

The SAW match is similar to the safety match except that it is richer in fuel, and gives a billowing somewhat wind-resistant flame. The phosphoms sulfide [1314-85-8] in the tip provides the ignitabiUty on any soHd surface, and a Httle of the same material in the base bulb adds to wind resistance, but otherwise the base is underbalanced in active materials to prevent self-ignition from mbbing during transportation. [Pg.1]

Fig. 2. Stmcture of phosphoms sulfides, where ( ) representsphosphoms and (Q) sulfur. See text. Fig. 2. Stmcture of phosphoms sulfides, where ( ) representsphosphoms and (Q) sulfur. See text.
The hydrolysis of phosphoms sulfides has been studied quantitatively. A number of products are formed (Table 6). Whereas phosphoms(V) sulfide reacts slowly with cold water, the reaction is more rapid upon heating, producing mainly hydrogen sulfide and orthophosphoric acid, H2PO4. At high pH, P4S Q hydroly2es to a mixture of products containing thiophosphates and sulfides. [Pg.363]

Manufacture. Phosphoms sulfides are manufactured commercially by direct reaction of the elements. Elemental phosphoms and sulfur are measured into a reaction vessel containing a heel of molten phosphoms sulfide. The reaction can be batch or continuous. The ratio of phosphoms to sulfur in the feed determines which phosphoms sulfur compound (Table 5) is formed. The reaction temperature can be the boiling point or lower. For the boiling reactor (27,28), the phosphoms sulfide product is first purified by distillation and then condensed to a Hquid. Alternatively, the Hquid product can be formed directly in a nondistiUed process (29—31), which may involve a subsequent distillation step (30), and in which the phosphoms is often cleaned up prior to use (30—32). For either process, the Hquid phosphoms sulfide product is soHdified, and usually sized to form a commercial material. [Pg.364]

Phosphoms sulfides Phosphoms chlorides Organic P compounds... [Pg.520]

Phosphorus sulfides ignite easily, and P4S3 is used in strike anywhere matches it is combined with KCIO3, and the compounds inflame when subjected to friction. (In safety matches, the head of the match contains KCIO3 and this reacts with red phosphorus which is combined with glass powder on the side of the match box see end-of-chapter problem 15.42). Whereas P4S3 does not react with water, other phosphoms sulfides are slowly hydrolysed (e.g. reaction 15.154). [Pg.539]

Thioketenes can be prepared in several ways, from carboxyHc acid chlorides by thionation with phosphoms pentasulfide [1314-80-3] 2 5 ketene dithioacetals by -elimination, from l,2,3-thiadia2oles with flash pyrolysis, and from alkynyl sulfides (thioacetylenes). The dimeri2ation of thioketenes to 2,4-bis(alkyHdene)-l,3-dithietane compounds occurs quickly. They can be cleaved back pyrolyticaHy (63). For a review see Reference 18. [Pg.476]

Diacyl peroxides have been reduced with a variety of reduciag agents, eg, lithium aluminum hydride, sulfides, phosphites, phosphines, and haUde ions (187). Hahdes yield carboxyUc acid salts (RO) gives acid anhydrides. With iodide ion and certain trivalent phosphoms compounds, the reductions are sufftcientiy quantitative for analytical purposes. [Pg.124]

Elemental phosphoms from the electrothermal process is a distilled product of high purity and yields phosphoric acid pure enough for most industrial uses without any further treatment. The main impurity is ca 20—100 ppm arsenic present in the phosphoms as the element and in the phosphoric acid as arsenious acid. To remove the arsenic, the phosphoric acid destined for food, pharmaceutical, and some industrial-grade appHcations is treated with excess hydrogen sulfide, filtered, and blown with air to strip out excess H2S. This treatment generally reduces the arsenic content of the phosphoric acid to less than 0.5 ppm. The small amount of filter cake is disposed of in approved chemical landfills. [Pg.327]

Phosphorus compounds exhibit an enormous variety of chemical and physical properties as a result of the wide range ia the oxidation states and coordination numbers for the phosphoms atom. The most commonly encountered phosphoms compounds are the oxide, haUde, sulfide, hydride, nitrogen, metal, and organic derivatives, all of which are of iadustrial importance. The hahde, hydride, and metal derivatives, and to a lesser extent the oxides and sulfides, are reactive iatermediates for forming phosphoms bonds with other elements. Phosphoms-containing compounds represented about 6—7% of the compound hstiugs ia Chemical Abstracts as of 1993 (1). [Pg.356]

DiaIkyl or diaryl dithiophosphoric acids are obtained readily from alcoholysis of phosphoms(V) sulfide. Thus, P4S q reacts with ethyl alcohol as follows ... [Pg.364]

Phosphoms(V) sulfide, an important commodity in the United States since about 1920, is the dominant commercial material. Phosphoms sesquisulfide, P4S2, has been made commercially since about 1900. Phosphoms heptasulfide was introduced as a small-scale commercial product in 1940. [Pg.364]

Shipping and Storage. Phosphoms(V) sulfide is stored and shipped in 208-L (55-gal) dmms containing 250 kg of product, portable closed aluminum bins containing 1800—3400-kg net weight, and railcars. P4S q is classified as a flammable soHd having the international shipping code of UN No. 1340. [Pg.365]

Phosphoms(V) sulfide is a mild skin irritant and may cause dermatitis in sensitive individuals. The primary health ha2ard results from the Hberation of hydrogen sulfide after contact with moisture. Contact with moisture also forms phosphoric acid. A secondary ha2ard is the formation of sulfur dioxide when phosphoms(V) sulfide bums. The oral LD q of in rats is 389 mg/kg the OSHA standard time-weighted average (TWA) is 1 mg /m (33). [Pg.365]

Uses. Phosphoms(V) sulfide is used in the manufacture of lubricating oil additives, insecticides, ore flotation agents, and specialty chemicals. Phosphoms sesquisulfide, P4S2, has been used extensively in the manufacture of stnkeanywhere matches (qv). In addition, small quantities are used in fireworks (see Pyrotechnics). [Pg.365]

The use of alkali or alkaline-earth sulfides cataly2es the reaction so that it is complete in a few hours at 150—160°C use of aluminum chloride as the catalyst gives a comparable reaction rate at 115°C. When an excess of sulfur is used, the product can be distilled out of the reactor, and the residue of sulfur forms part of the charge in the following batch reaction. The reaction is carried out in a stainless steel autoclave, and the yield is better than 98% based on either reactant. Phosphoms sulfochloride is used primarily in the manufacture of insecticides (53—55), such as Parathion. [Pg.371]

Nitrogen and sodium do not react at any temperature under ordinary circumstances, but are reported to form the nitride or azide under the influence of an electric discharge (14,35). Sodium siHcide, NaSi, has been synthesized from the elements (36,37). When heated together, sodium and phosphoms form sodium phosphide, but in the presence of air with ignition sodium phosphate is formed. Sulfur, selenium, and tellurium form the sulfide, selenide, and teUuride, respectively. In vapor phase, sodium forms haHdes with all halogens (14). At room temperature, chlorine and bromine react rapidly with thin films of sodium (38), whereas fluorine and sodium ignite. Molten sodium ignites in chlorine and bums to sodium chloride (see Sodium COMPOUNDS, SODIUM HALIDES). [Pg.163]

Phosphoms trichloride and pentachloride form sodium chloride and sodium phosphide, respectively, in the presence of sodium. Phosphoms oxychloride, POCl, when heated with sodium, explodes. Carbon disulfide reacts violendy, forming sodium sulfide. Sodium amide (sodamide), NaNH2, is formed by the reaction of ammonia gas with Hquid sodium. SoHd sodium reacts only superficially with Hquid sulfur dioxide but molten sodium and gaseous... [Pg.163]

Preparation. Thiophosgene forms from the reaction of carbon tetrachloride with hydrogen sulfide, sulfur, or various sulfides at elevated temperatures. Of more preparative value is the reduction of trichi oromethanesulfenyl chloride [594-42-3] by various reducing agents, eg, tin and hydrochloric acid, staimous chloride, iron and acetic acid, phosphoms, copper, sulfur dioxide with iodine catalyst, or hydrogen sulfide over charcoal or sihca gel catalyst (42,43). [Pg.131]

If tin and sulfur are heated, a vigorous reaction takes place with the formation of tin sulfides. At 100—400°C, hydrogen sulfide reacts with tin, forming stannous sulfide however, at ordinary temperatures no reaction occurs. Stannous sulfide also forms from the reaction of tin with an aqueous solution of sulfur dioxide. Molten tin reacts with phosphoms, forming a phosphide. Aqueous solutions of the hydroxides and carbonates of sodium and potassium, especially when warm, attack tin. Stannates are produced by the action of strong sodium hydroxide and potassium hydroxide solutions on tin. Oxidizing agents, eg, sodium or potassium nitrate or nitrite, are used to prevent the formation of stannites and to promote the reactions. [Pg.64]

Inorga.nicNIa.teria.ls. These include acids (sulfuric, nitric, hydrochloric, and phosphoric), bases (caustic soda, caustic potash, soda ash, sodium carbonate, ammonia, and lime), salts (sodium chloride, sodium nitrite, and sodium sulfide) and other substances such as chlorine, bromine, phosphoms chlorides, and sulfur chlorides. The important point is that there is a significant usage of at least one inorganic material in all processes, and the overall toimage used by, and therefore the cost to, the dye industry is high. [Pg.285]

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]

The P=C bond of ), a -phosphoranes is also accessible to a 1,3-dipolar cycloaddition reaction. The formation of 97 (Scheme 8.23), of 3,5-dihydro-1,2,4-diazaphosphole sulfide 132 from an amino(methylene)thioxophosphorane (190) and of phosphirane imine 133 from an amino(imino)alkylidenephosphorane (191) (Scheme 8.29) illustrate the chemical behavior of phosphaalkenes containing a A, a -phosphoms atom. [Pg.567]

Interaction of a mixture of sulfur and the oxide under inert atmosphere above 160°C to form tetraphosphoms hexaoxide tetrasulfide is violent and dangerous on scales of working other than small [1], A safer procedure involving distillation of phosphoms(V) oxide and phosphoms(V) sulfide is described [2],... [Pg.1968]

In addition, mixed sulfide selenide systems such as P4S2Se are also known, while P Te bonds are found in BaP4Te2. This new material is generated by direct reaction of the elements at 475 °C and consists of P4Tc2 chains made up of six-membered phosphoms rings linked to tellurium atoms (47). The P-Te... [Pg.3711]


See other pages where Phosphoms sulfide is mentioned: [Pg.269]    [Pg.539]    [Pg.269]    [Pg.539]    [Pg.378]    [Pg.241]    [Pg.489]    [Pg.238]    [Pg.443]    [Pg.117]    [Pg.357]    [Pg.365]    [Pg.176]    [Pg.95]    [Pg.327]    [Pg.327]    [Pg.332]    [Pg.459]    [Pg.784]    [Pg.75]    [Pg.327]    [Pg.332]    [Pg.110]    [Pg.243]    [Pg.176]    [Pg.3500]   
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