Abstract: Rinse acid collected from an aluminum bright dipping operation is reacted with soda alkalies at 80.degree. C or higher to yield a solution of trisodium phosphate, Na.sub.3 PO.sub.4, sodium aluminate, NaAlO.sub.2, sodium nitrate, NaNO.sub.3, and trace insolubles. The hot solution is quickly filtered to remove all insoluble impurities and then cooled so that the trisodium phosphate crystallizes out which, after filtering, leaves a mother liquor containing some remaining trisodium phosphate and soluble impurities, namely, sodium aluminate and sodium nitrate. The mother liquor is then recycled repeatedly with further batches of rinse acid to maximize the phosphate recovery.

Abstract: Single crystals of neodymium pentaphosphate greater than one centimeter in size and of high purity and quality are grown from polyphosphoric acid solutions using the combination of a dilute solution, seeding, growth temperatures of 500.degree. to 650.degree. C, and a double crucible configuration.

Abstract: Stable aqueous ammonium phosphate containing a higher proportion of polyphosphates is obtained by reacting phosphoric acid with ammonia in the presence of sulfuric, nitric or hydrochloric acids under conditions sufficient to produce a partially neutralized melt containing polymeric phosphates at a temperature between 400.degree. and about 750.degree. F. by the autogenous heat of neutralization, quenching and further neutralizing the melt.

Abstract: An advantageous process of producing Maddrell salt which is substantially free of water-soluble by-products is described. The resulting substantially water-insoluble Maddrell salt is especially useful as polishing and cleaning agent in toothpaste.

Abstract: There are disclosed methods for removing fluorine values from fluorine-containing waste waters, in which aluminum ions are added to fluorine-containing waste water to convert fluorine to hydroxyfluoride complexes, adding phosphoric acid or phosphate and calcium compound are added to form fluoride apatite with residual fluorine in the waste water, and the hydroxy-fluoride complex and fluoride apatite are removed from the waste water.

Abstract: Zirconium phosphate is made by reacting a zirconium salt with phosphoric acid or a phosphate in a liquid medium, the zirconium salt being insoluble in water. A granular product may be obtained having a grain size controlled by that of the salt. The product may be used as an ion-exchange material.

Abstract: Wet-process phosphoric acid is partially purified by extraction with an organic solvent followed by scrubbing with a portion of the aqueous phosphoric acid from a water-stripping unit, then water-stripping and base-stripping. At the water-stripping stage, all the remaining impurities and approximately two-thirds of the P.sub.2 O.sub.5 are transferred from the organic to the aqueous phase, which renders the other one-third P.sub.2 O.sub.5, subsequently recovered by base-stripping, essentially free of impurities. The bulk of the aqueous phosphoric acid from the water-stripping is purified further by precipitating the impurities with an alkali metal hydroxide or carbonate. The precipitate is filtered off and the filtrate used for base-stripping. The resulting aqueous solution from base-stripping is adjusted to a desired alkali metal-to-phosphate ratio and used for manufacture of high purity alkali metal phosphate in general and particularly sodium tripolyphosphate.

Abstract: Crystalline AlH.sub.3 (PO.sub.4).sub.2.3H.sub.2 O is obtained from an aqueous solution of aluminum phosphate containing a molar ratio of Al.sub.2 O.sub.3 :P.sub.2 O.sub.5 of from 1:2 to 1:6 and an organic solvent that is miscible with water. The product is useful in diminishing the setting time of hydraulic binders.

Abstract: A catalyst for purifying exhaust and waste gases comprisingA. a support substrate comprising 2 to 100% by weight of an oxide complex of titanium and phosphorus containing titanium and phosphrus in such a proportion that the molar ratio of TiO.sub.2 to P.sub.2 O.sub.5 is from 5.0 to 0.5 and 98 to 0% by weight of aluminum oxide, andB. supported on said substrate as a catalytic substance, 2 to 300 parts by weight, calculated as metal oxide per 100 parts by weight of the support substrate (A), of at least one heavy metal selected from the group consisting of Ni, Cu, Cr, Fe, Co, Mn, Bi, V, W, Mo, Sn, Zn, Zr, Pb, Sb, Ti, Ta, Cd and Nb, or 0.01 to 1.0 part by weight, calculated as metal per 100 parts by weight of the support substrate (A), of at least one noble metal selected from the group consisting of Pt, Pd, Rh, Ir, Os and Ru.

Abstract: Ammonium polyphosphates are prepared by a process which comprises heating melamine orthophosphate prepared from impure wet-process phosphoric acid in a stream of gaseous ammonia at a temperature between 150.degree. C and 210.degree. C to produce a mixture of melamine and relatively pure short-chain ammonium polyphosphates. The solid product is extracted with water to remove the ammonium polyphosphates and free the insoluble, crystalline melamine for recycle. Thus, the only starting materials consumed in the process are phosphoric acid and ammonia.

Abstract: Self-activated ultraviolet-emitting hafnium pyrophosphate phosphors. Up to about 20 mole percent of the hafnium may be substituted with one or more of zirconium, germanium and silicon. The phosphors, which may be excited by ultraviolet radiation, x-rays and electron beams, may be used as energy converters in photodevices. The phosphors may be prepared by heating a mixture of a hafnium compound, a phosphate (no added activator ions) and optionally compounds of one or more of zirconium, germanium and silicon, which are present in proportions up to about 25 mole percent of the hafnium present, at about 1000.degree. to 1300.degree. C in air.

Abstract: Phosphoric acids having H.sub.2 0/P.sub.2 O.sub.5 mole ratios of about 4.5 or less are converted to aqueous solutions of ammonium polyphosphates of which at least about 40 percent of the P.sub.2 O.sub.5 is present as acyclic polyphosphates. The reaction is conducted at 500.degree. to about 750.degree. F. sufficient to increase the polymeric P.sub.2 O.sub.5 content at least 10 percent by reacting a highly dispersed, unconfined acid spray with substantially anhydrous ammonia. High conversions to polymeric species are obtained while minimizing both reactor fouling when using impure wet-process acids, and corrosion occurring with either wet-process or "white" acids.

Abstract: A process for the production of monobasic potassium phosphate from wet process phosphoric acid and potassium sulfate by ion exchange. The application of the process is the production of monobasic potassium phosphate by ion exchange from wet phosphoric acid produced by the reaction of sulfuric acid on apatite rock and by-product potassium sulfate from processes for the recovery of aluminum from alunite.

Abstract: Complex phosphates of aluminum containing a halogen and chemically-bound molecule of a hydroxy compound, namely, water. A typical example is a complex phosphate having the empirical formulate AlPClH.sub.11 O.sub.9. They are most conveniently prepared by the reaction of an aluminum halide with water and orthophosphoric acid, under relatively cool conditions. The compounds are generally soluble in water and polar organic solvents. They decompose at low temperatures to give aluminum orthophosphate, thereby providing a method for producing aluminum phosphate in many forms, for example, fibers, coatings, binders and fine particles, from a solution in water or organic solvents.

Abstract: Acicula of rare earth pentaphosphates, of a diameter and length ideal for waveguiding laser-type applications, are grown by controlling the rate of metaphosphoric acid conversion by introducing water vapor into an inert gas atmosphere continuously flowed through the reaction zone. The required amount of water vapor in the reaction zone has to be within the range between approximately 14 grams per cubic meter and 290 grams per cubic meter of the flowing atmosphere. This control is implemented by bubbling the inert gas atmosphere through a water bath at temperatures between 15.degree. and 80.degree. C. It is believed that the control of the water vapor eliminates problems of supersaturation in the forming of pentaphosphoric crystals in the growth solution and thereby promotes their natural tendency to form purely chainlike polymer structures.

Abstract: A solid source consisting essentially of high purity aluminum metaphosphate, Al(PO.sub.3).sub.3 is used for introducing elemental phosphorus into P-type silicon chips or wafers of semi-conductor grade. The aluminum metaphosphate functions as a source for the controlled release of P.sub.2 O.sub.5 vapors which are directed to the desired face of the silicon wafer. The reverse side of the silicon wafer receives little or no phosphorus and consequently retains its character as P-type silicon.

Abstract: Synthetic rutile is produced from a titaniferous slag derived from ilmenite. Ilmenite concentrates are reduction smelted to remove iron as a high grade pig iron byproduct and to enrich the remaining slag phase in titanium. Oxidation of the slag and aging at high temperature in the presence of a titanium pyrophosphate flux converts the titanium bearing phases to discrete rutile crystals and a phosphate glass phase containing most of the associated impurities. Rutile is separated from the glassy matrix by attrition scrubbing aged, ground slag in dilute mineral acid solutions.

Abstract: A process for the manufacture of alkali metal polyphosphates having a predetermined crystalline form, in which a mixture of alkali metal orthophosphates having a molar ratio of alkali metal oxide to phosphoric anhydride between 1 and 2 is first granulated, the resulting granules are dried and then are subjected to thermal treatment in the presence of aqueous vapor.

Abstract: Method for production of a zeolitic material represented by the formula:R.sub.x H.sub.5.sub.-x (Al.sub.y Fe.sub.1.sub.-y).sub.4 (P.sub.l As.sub.1.sub.-l).sub.3 O.sub.16.zH.sub.2 Owherein R represents Na or K, x, y, z and l are numerical values of O.ltoreq.x.ltoreq.5, O.ltoreq.y.ltoreq.1, Z.ltoreq.9 and O.ltoreq.l.ltoreq.1, respectively; which comprises preparing an aqueous solution by dissolving (1) at least one source of aluminum and iron, (2) at least one source of phosphorus and arsenic and (3) at least one source of sodium and potassium in water in the ranges expressed in terms of the molar ratios of their oxides of3.5.ltoreq.(Al, Fe).sub. 2 O.sub.3 /(P, As).sub. 2 O.sub.5 .ltoreq.4.5and(K, Na).sub.2 O/(Al, Fe) .sub.2 O.sub.3 >0.12adjusting the pH of the solution to within the range of the cross-hatched area in FIGS. 1 to 4 and heating the solution at 150 to 250.degree.C in a closed vessel to crystallize the zeolitic material and recovering the objective zeolitic material.

Abstract: Production of substantially water-insoluble linear ammonium polyphosphates of the general formula (NH.sub.4 PO.sub.3).sub.n, in which n is a number between 10 and 1000. To this end, substantially equimolecular proportions of ammonium orthophosphate and phosphorus pentoxide are reacted by heating them to temperatures within the range 170.degree. and 350.degree.C in the presence of gaseous ammonia. The reaction is effected while continuously and simultaneously mixing, kneading and comminuting the reaction material in a reactor. The reactor is closed, provided with means for the supply of solid feed material, a gas inlet and a gas outlet, a discharge opening for the removal of final product, and with mixing, kneading and comminuting implements which are rotatably secured to the inside of the reactor.

Abstract: A continuous process for preparing crystalline, water-insoluble ammonium polyphosphates of controlled pH utilizing a continuous reaction arena, is disclosed.

Abstract: A method for the preparation of pyrophosphates such as SiP.sub.2 O.sub.7 is disclosed, whereby the undesired formation of by-products such as Si.sub.2 P.sub.2 O.sub.9 is minimized. Such pyrophosphates are particularly suitable for the formation of solid semi-conductor diffusion sources, wherein the presence of by-product is seriously detrimental.

Abstract: Particulate carbonaceous matter in ammonium polyphosphate liquid made from impure wet-process phosphoric acid is removed by intimately mixing the liquid with a combination of selected organic flocculating agents and then transferring the mixture to a separation vessel where the particulate carbonaceous matter floats rapidly to the surface. Clarified liquid that contains essentially no particulate carbonaceous matter is withdrawn from the bottom of the separation vessel. The particulate carbonaceous matter and a minor portion of the input ammonium polyphosphate liquid are withdrawn from the top of the separation vessel and processed into fluid or solid fertilizers.

Abstract: Aqueous AlF.sub.3 enriched crystallization mother liquors contaminated with P.sub.2 O.sub.5 values and having less than 5% free acidity are treated with a material which provides bismuth ions in the mother liquor in amounts small enough to insure that the Bi/PO.sub.4 mole ratio remains below about 1.05. Under these conditions, the bismuth and P.sub.2 O.sub.5 react essentially quantitatively to form a BiPO.sub.4 precipitate by which the P.sub.2 O.sub.5 can be separated from the mother liquor. Bismuth can be regenerated from the BiPO.sub.4 and recycled for further use in the process.The invention finds utility in the preparation of AlF.sub.3 by the reaction of an aluminum ore and P.sub.2 O.sub.5 contaminated HF or H.sub.2 SiF.sub.6 such as that available as a by-product of wet process phosphoric acid manufacture. The AlF.sub.3 reaction product is recovered by a crystallization step which, because it is normally only about 70 to 90% efficient, produces a mother liquor containing substantial amounts of AlF.sub.3.

Abstract: A solution of sodium ammonium phosphate is prepared by reacting monoammonium phosphate with sodium carbonate in a vertical column having vapor-liquid contact means at a temperature in the range of 150.degree.F. up to the boiling point.

Abstract: Waste material consisting substantially of contaminated phosphorous acid is utilized. To this end, the phosphorous acid is introduced, with agitation into a liquid phase. Liquid phase and phosphorous acid are maintained in a ratio by volume between 1:1 and 10:1. The liquid phase is placed in a reactor, maintained between 250.degree. and 400.degree.C and selected from a phosphoric acid of the general formula H.sub.n.sub.+2 P.sub.n O.sub.3n.sub.+1, in which n substantially stands for a number between 1 and 5. Resulting hydrogen phosphide is removed. In the event of continuous operation, newly formed liquid phase is removed from the reactor, at the same rate as it is being formed.

Abstract: There is disclosed a method and apparatus for the production of ammonium polyphosphate solutions of high concentrations from phosphoric acid and ammonia. The process is ideally suited for the production of such solutions from wet-process phosphoric acid which has a P.sub.2 O.sub.5 content of from 56 to about 70 weight percent, impurity-free basis, and which, preferably, contains from 5 to about 50 percent of its phosphorus present as polyphosphoric acid. The method comprises introducing the phosphoric acid into a reactor bearing a Teflon liner and reacting it therein with vapors of ammonia while controlling the amount of ammonia from 0.2 to about 0.3 pound ammonia per pound of P.sub.2 O.sub.5 in the feed acid, sufficient to achieve a peak reaction temperature in the reactor between about 525.degree. and 775.degree.F., the absolute value of which is dependent on the bulk water content of the feed acid.

Abstract: A single crystal of gallium phosphide including 0.5 atomic ratio or less of indium is grown from a melt consisting of indium, gallium and phosphorous with an atomic ratio of gallium to phosphorous equal to at least 2.0.

Abstract: Improved stable suspension liquid fertilizers based on ammonia and phosphoric acid obtained by the wet method, and combining both a high content of fertilizing elements and a long storage life are prepared by ammoniating the phosphoric acid with gaseous ammonia in two steps at a temperature of from 90.degree.C to 120.degree.C until a pH of between 6 and 8 is attained, rapidly cooling the resulting ammonium phosphate suspension to a temperature of from 0.degree.C to 35.degree.C, and during the cooling adding a suspending agent to the suspension while maintaining the suspension under stirring.

Abstract: Aqueous monoammonium phosphate is reacted at elevated temperature with sodium carbonate in a vertical column having vapor-liquid contact means to produce an aqueous solution of sodium ammonium phosphate having a reduced carbon dioxide content. The sodium ammonium phosphate solution is treated in a second such column at elevated temperature and pressure to produce ammonia and an ammonia-free solution of alkali metal orthophosphate having a desired alkali metal to phosphorus molar ratio.

Abstract: When titanium phosphate is used as a white pigment to an article of which surface comprises polyolefin composition, the article is remarkably whitened.

Abstract: A process of carbo-chlorination of AlPO.sub.4 wherein AlPO.sub.4 or AlPO.sub.4 -containing material is introduced into a reactor along with chlorinating agents and a source of carbon. The reactor is heated to approximately 600.degree. to 1200.degree.C and forms aluminum chlorides, phosphorous oxides, phosphorous chlorides, phosphorous oxychlorides and carbon oxides. These reaction products are then separated into three fractions by condensation, the first fraction being P.sub.2 O.sub.5, the second fraction being AlCl.sub.3 and AlCl.sub.3 .POCl.sub.3 and the third fraction being remaining gasses, namely PCl.sub.3, PCl.sub.5, P.sub.2 O.sub.3, CO and CO.sub.2. The second fraction is reacted in a further reactor to give AlCl.sub.3 and P.sub.2 O.sub.3 which are separated by distillation. The phosphorous chlorides from the third fraction are oxidized, along with the P.sub.2 O.sub.3 of the second fraction, to form P.sub.2 O.sub.5.