Abstract: N.sub.2 F.sub.3 SnF.sub.5 is formed by reacting N.sub.2 F.sub.3 SbF.sub.6 and Cs.sub.2 SnF.sub.6 in the presence of HF. N.sub.2 F.sub.3 SnF.sub.5 is useful as a component of NF.sub.3 -F.sub.2 gas generating compositions.

Abstract: Urea bodies, such as crystals, prills, pellets and the like, with a reduced caking tendency are obtained by processing such bodies or a concentrated urea solution or melt produced in the urea synthesis, which is processed to form such bodies, with an aqueous solution containing an effective amount of dimethylol urea and/or trimethylol urea, which solution contains about 2 to about 5 mols bonded and free formaldehyde per mol of urea.

Abstract: A process for pre-treating platinum/palladium catalysts, used in the preparation of hydroxylamine, comprising contacting the same with an aqueous salt solution, inhibits (a) the decomposition of hydroxylamine and (b) the consequent formation of explosive mixtures of N.sub.2 O with hydrogen or hydrocarbons.

Abstract: Process for the recovery of H.sub.2 SO.sub.4 from dilute sulfuric acid solutions containing combined acid sulfates by heating these solutions in the presence of excess ammonium sulfate to a temperature from between about 100.degree. and 160.degree. C. until a concentration of free H.sub.2 SO.sub.4 between 50 and 59% by weight is obtained to precipitate the combined acid sulfates.

Abstract: A urea synthesis process for converting ammonia and carbon dioxide to urea is improved by providing an easy means of maintaining the urea synthesis zone in the process at a constant temperature. In the process the starting CO.sub.2 and up to and including 100 percent of the starting NH.sub.3 are reacted in a heat-recovery zone maintained at a urea synthesis pressure. Some of the heat of reaction is removed. The molar ratio of NH.sub.3 to CO.sub.2 which is fed into the heat-recovery zone is less than 4. The reaction mixture and the rest of the starting NH.sub.3 are fed into a urea synthesis zone maintained at urea synthesis pressure to produce urea. The improvement involves adjusting the amount of starting ammonia which is fed into the urea synthesis zone in response to any change in the temperature in the urea synthesis zone so that the urea synthesis zone is maintained at a substantially fixed temperature.

Abstract: Wet process phosphoric acid prepared by treating phosphate rock with sulfuric acid and separating calcium sulfate, is purified to obtain a purified phosphoric acid by (a) an acid extracting section contacting the wet process phosphoric acid and a phosphoric acid solution containing impurities obtained in the scrubbing section with an organic solvent in the presence of the hydrochloric acid required for extracting a substantial amount of the phosphoric acid component; (b) a scrubbing section contacting the extract obtained in the acid extracting section with aqueous phosphoric acid or water while maintaining the chloride ion concentration in the aqueous phase in the range of 20 to 40 g/liter as Cl; (c) an acid stripping section contacting the purified extract obtained in the scrubbing section with water and (d) an adsorbing section contacting the extracted phosphoric acid obtained in the acid stripping section with an anion-exchange resin.

Abstract: Red phosphorus, usually in amorphous form, is obtained by heating liquid white phosphorus at a temperature of between 250.degree. and 590.degree. C. while the phosphorus is subjected to a pressure greater than the theoretical vapor pressure of white phosphorus at the heating temperature. The application of such pressure minimizes phosphorus vapor formation during the conversion to red phosphorus. The process may be carried out by feeding liquid white phosphorus into an extrusion head heated to the reaction temperature while subjecting the white phosphorus to the appropriate pressure in the extrusion head, the red phosphorus being extruded from the extrusion head into an inert atmosphere. Alternatively, molten white phosphorus in droplet form may be pumped into an inert immiscible heat exchange fluid, such as, lead, at the reaction temperature, the appropriate pressure applied in the fluid and particulate red phosphorus separated from the fluid.

Abstract: Exothermic reaction of a fluid stream is carried out with recycle and addition of hot reacted fluid to the colder feed fluid stream, so as to raise the feed fluid stream to operable reaction temperatures and produce optimum reaction rate. The addition of hot reacted fluid is carried out by reactor-internal ejector-effected aspiration of a portion of the hot reacted fluid discharged from the reaction zone into the cold feed fluid. The resulting combined fluid stream is passed to the reaction zone. The balance of the hot reacted fluid not aspirated into the cold feed fluid is passed to product recovery or utilization. The invention is especially applicable to exothermic catalytic reactions.

Abstract: An improved process for the purification of wet-process phosphoric acid (WPPA) with acetone and ammonia. The main product is the purified acid and a byproduct is the impure acid fraction in a liquid form containing most of the impurities including the added ammonia. The WPPA is mixed with acetone and the specified amount of ammonia to form two liquid phases that separate rapidly. The top layer contains about 75 percent of the phosphoric acid, nearly all the acetone, and a small fraction of the impurities. The bottom liquid layer has a viscosity usually in the range of 40 to 2500 centipoises, depending on the acid concentration and the amount of ammonia used. The acetone is distilled from the two liquid phases for recycle to the process.

Abstract: Hydrogen Fluoride is manufactured from fluorosilicic acid. The fluorosilicic acid is reacted with ammonia to produce aqueous ammonium fluoride and solid silica. The ammonium fluoride is hydrolised in the presence of a mixture of ammonium fluoride and ammonium bifluoride, and the net production of ammonium bifluoride is converted to sodium bifluoride. The sodium bifluoride is decomposed by heating to hydrogen fluoride gas.

Abstract: Phosphatic raw materials are treated with phosphoric acid to obtain monocalcium phosphate which is dissociated with an organic solvent to yield high grade phosphoric acid and fertilizer grade dicalcium phosphate.

Abstract: This invention relates to a process for the thermal decomposition of metal nitrates which decompose below a temperature of about 400.degree. C. to form the corresponding metal oxide as well as oxides of nitrogen, said process involving distributing said nitrate over previously formed oxide and conducting said decomposition under "muffle" conditions such that said decomposition occurs in an atmosphere predominantly comprised of the vapors evolved during the thermal decomposition.

Abstract: An improvement of the SNAM ammonia-stripper integrated urea process is disclosed, wherein a gaseous stream obtained by decomposing hydrocarbons is fed to an adiabatic ammonia stripper placed downstream of a carbamate decomposer, the adiabatic stripper also receiving a solution of urea which is rich in ammonia coming from the carbamate decomposer. The thus enriched gaseous stream (NH.sub.3, CO.sub.2, H.sub.2 O) is processed in a CO.sub.2 -absorber (or carbamate reactor) and the process proceeds in the urea synthesis reactor. Recycling and recovery loops are provided between the several reaction and/or decomposing units. Surprisingly, enough, the stripping on NH.sub.3 and CO.sub.2 takes place adiabatically and the drop of the CO.sub.2 partial pressure in the stream fed to the carbamate reactor has no bearing on the efficiency of the carbamate conversion which, according to the current technical teachings, requires an increase of the CO.sub.2 partial pressure.

Abstract: Hydrogen cyanide is produced by reacting an organic nitrile with hydrogen at temperatures of 400-700.degree. C in the presence of selected catalysts. Exemplary is the reaction of benzonitrile and hydrogen at 600.degree. C in the presence of chromia on alumina to produce hydrogen cyanide.

Abstract: Process and apparatus for purifying crude wet-processed phosphoric acid containing free sulphuric acid. To this end, the wet-processed phosphoric acid is treated in a reaction zone, at a temperature of 70.degree. C to 100.degree.

Abstract: Mono- and dibasic alkali metal periodates are prepared by reacting tri-, tetra- and pentabasic alkali metal periodates with a substance having a relative acidity value, pKa, of from 3 to 16 at a temperature of from 0.degree. to 100.degree. C at molar ratios of periodate to moles of acidic substance of 1:1 to 1:1000. The mono- and dibasic alkali metal periodates are useful in oxidizing olefins such as propylene to the corresponding oxide such as propylene oxide.

Abstract: Precipitated calcium carbonate of uniform particle size is produced by contacting a suspension of calcium hydroxide with a carbon dioxide-containing gas in three steps. The particle size of precipitated calcium carbonate can be optionally selected by suitably adjusting reaction conditions.

Abstract: Ammonium sulfamate is prepared by introducing sulfur trioxide and ammonia into a pressure vessel that contains a melt essentially consisting of ammonium sulfonate and ammonium imido disulfonate using a molar ratio of NH.sub.3 to SO.sub.3 of 1.5 to 1.99:1. The gases that accumulate on top of the molten phase are not removed from the pressure vessel.

Abstract: The fluoride values of fluorapatite ores can be recovered by using reactive metal compounds, e.g., the sulfates, phosphates or hydroxides of aluminum, iron, titanium, zirconium, antimony or chromium, to tie up the fluorides during acid attack on the ores and thus minimize the formation of fluosilicic acid. The soluble metal fluoride salts formed can subsequently be separated and treated with acid to recover hydrogen fluoride.

Abstract: A method is disclosed for scrubbing SO.sub.2 and NO.sub.x containing gases with iron sulfide. The reaction proceeds only to the formation of FeS.sub.2 and FeSO.sub.4 without significant formation of sulfur or iron oxide. The reaction products are subsequently regenerated to FeS by heating and can be recycled for further scrubbing operations; elemental sulfur is recovered as a by-product.