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Phosphate calcium

Phosphorus, like nitrogen, is an essential constituent of living matter where it may be partly in combination (as phosphate groups) with organic groups, for example in lecithin and egg yolk, or mainly in inorganic form, as calcium phosphate(V), in bones and teeth. [Pg.208]

Industrially. phosphoric(V) acid is manufactured by two processes. In one process phosphorus is burned in air and the phos-phorus(V) oxide produced is dissolved in water. It is also manufactured by the action of dilute sulphuric acid on bone-ash or phosphorite, i.e. calcium tetraoxophosphate(V). Ca3(P04)2 the insoluble calcium sulphate is filtered off and the remaining solution concentrated. In this reaction, the calcium phosphate may be treated to convert it to the more soluble dihydrogenphosphatc. CafHjPOjj. When mixed with the calcium sulphate this is used as a fertiliser under the name "superphosphate . [Pg.246]

Never found free in nature, it is widely distributed in combination with minerals. Phosphate rock, which contains the mineral apatite, an impure tri-calcium phosphate, is an important source of the element. Large deposits are found in Russia, in Morocco, and in Florida, Tennessee, Utah, Idaho, and elsewhere. [Pg.36]

White phosphorus may be made by several methods. By one process, tri-calcium phosphate, the essential ingredient of phosphate rock, is heated in the presence of carbon and silica in an electric furnace or fuel-fired furnace. Elementary phosphorus is liberated as vapor and may be collected under phosphoric acid, an important compound in making super-phosphate fertilizers. [Pg.37]

Bone-ash, calcium phosphate, is used to create fine chinaware and to produce mono-calcium phosphate, used in baking powder. [Pg.37]

Valentinite, see Antimony(III) oxide Verdigris, see Copper acetate hydrate Vermillion, see Mercury(II) sulflde Villiaumite, see Sodium fluoride Vitamin B3, see Calcium (+)pantothenate Washing soda, see Sodium carbonate 10-water Whitlockite, see Calcium phosphate Willemite, see Zinc silicate(4—)... [Pg.275]

Nickel halide complexes with amines give mixtures of linear polymer and cychc trimers (30). Nickel chelates give up to 40% of linear polymer (31). When heated with ammonia over cadmium calcium phosphate catalysts, propargyl alcohol gives a mixture of pyridines (32). [Pg.104]

Phosphoms oxyfluoride is a colorless gas which is susceptible to hydrolysis. It can be formed by the reaction of PF with water, and it can undergo further hydrolysis to form a mixture of fluorophosphoric acids. It reacts with HF to form PF. It can be prepared by fluorination of phosphoms oxytrichloride using HF, AsF, or SbF. It can also be prepared by the reaction of calcium phosphate and ammonium fluoride (40), by the oxidization of PF with NO2CI (41) and NOCl (42) in the presence of ozone (43) by the thermal decomposition of strontium fluorophosphate hydrate (44) by thermal decomposition of CaPO F 2H20 (45) and reaction of SiF and P2O5 (46). [Pg.225]

Table 6 Hsts the leavening acids and the corresponding rates of reaction. The leavening acids most frequently used iaclude potassium acid tartrate, sodium aluminum sulfate, 5-gluconolactone, and ortho- and pyrophosphates. The phosphates iaclude calcium phosphate [7758-23-8] CaHPO, sodium aluminum phosphate, and sodium acid pyrophosphate (66). Table 6 Hsts the leavening acids and the corresponding rates of reaction. The leavening acids most frequently used iaclude potassium acid tartrate, sodium aluminum sulfate, 5-gluconolactone, and ortho- and pyrophosphates. The phosphates iaclude calcium phosphate [7758-23-8] CaHPO, sodium aluminum phosphate, and sodium acid pyrophosphate (66).
The amount of each element required in daily dietary intake varies with the individual bioavailabihty of the mineral nutrient. BioavailabiUty depends both on body need as deterrnined by absorption and excretion patterns of the element and by general solubiUty, and on the absence of substances that may cause formation of iasoluble products, eg, calcium phosphate, Ca2(P0 2- some cases, additional requirements exist either for transport of substances or for uptake or binding. For example, calcium-binding proteias are iavolved ia calcium transport an intrinsic factor is needed for vitamin cobalt,... [Pg.374]

One method of treatment is to inject calcitonin, which decreases blood Ca " concentration and increases bone calcification (33). Another is to increase the release of calcitonin into the blood by increasing the blood level of Ca " ( 4). This latter treatment is accompHshed by increasing Ca " absorption from the intestine requiring dietary calcium supplements and avoidance of high phosphate diets. The latter decrease Ca " absorption by precipitation of the insoluble calcium phosphate. [Pg.377]

Wet-process acid is manufactured by the digestion of phosphate rock (calcium phosphate) with sulfuric acid. Depending on availabiHty, other acids such as hydrochloric may be used, but the sulfuric-based processes are by far the most prevalent. Phosphoric acid is separated from the resultant calcium sulfate slurry by filtration. To generate a filterable slurry and to enhance the P2O5 content of the acid, much of the acid filtrate is recycled to the reactor. [Pg.327]

Calcium Phosphates. The alkaline-earth phosphates are generally much less soluble than those of the alkaH metals. Calcium phosphates include the most abundant natural form of phosphoms, ie, apatites, Ca2Q(P0 3X2, where X = OH, F, Cl, etc. Apatite ores are the predominant basic raw material for the production of phosphoms and its derivatives. Calcium phosphates are the main component of bones and teeth. After sodium phosphates, the calcium salts are the next largest volume technical- and food-grade phosphates. Many commercial appHcations of the calcium phosphates depend on thek low solubiHties. [Pg.333]

Several compounds of the CaO—P2O3—H2O system are given in Table 8. The common names for the mono-, di-, and tricalcium phosphates arise from the traditional double-oxide formulas, CaO 2i5p T2O3, 2CaO H2O +205, and 3CaO +205, respectively. These terms are routinely used in industry. With the exception of the monocalcium salt, the calcium phosphates are all sparingly soluble. [Pg.333]

Both monocalcium phosphate and dicalcium phosphate dissolve incongmently in water, disproportionating to more basic calcium phosphate and phosphoric acid. The extent of these reactions varies with the temperature and the amount of water. If water is added gradually to anhydrous monocalcium phosphate, equiUbrium conditions first correspond to a mixture of the anhydrous salt and its monohydrate. After conversion to the monohydrate, further reaction affords dicalcium phosphate plus free phosphoric acid. Dicalcium phosphate decomposes in aqueous solution to the more basic hydroxyapatite and phosphoric acid via intermediate octacalcium phosphate. The compHcated stepwise conversion of the acidic mono- and dicalcium phosphates to hydroxyapatite is summarized in equations 6—9. The kinetics are quite complex. [Pg.334]

Tricalcium phosphate, Ca2(P0 2> is formed under high temperatures and is unstable toward reaction with moisture below 100°C. The high temperature mineral whidockite [64418-26-4] although often described as P-tricalcium phosphate, is not pure. Whidockite contains small amounts of iron and magnesium. Commercial tricalcium phosphate prepared by the reaction of phosphoric acid and a hydrated lime slurry consists of amorphous or poody crystalline basic calcium phosphates close to the hydroxyapatite composition and has a Ca/P ratio of approximately 3 2. Because this mole ratio can vary widely (1.3—2.0), free lime, calcium hydroxide, and dicalcium phosphate may be present in variable proportion. The highly insoluble basic calcium phosphates precipitate as fine particles, mosdy less than a few micrometers in diameter. The surface area of precipitated hydroxyapatite is approximately... [Pg.334]

Hydroxyapatite, Ca2Q(PO (OH)2, may be regarded as the parent member of a whole series of stmcturaHy related calcium phosphates that can be represented by the formula M2q(ZO X2, where M is a metal or H O" Z is P, As, Si, Ga, S, or Cr and X is OH, F, Cl, Br, 1/2 CO, etc. The apatite compounds all exhibit the same type of hexagonal crystal stmcture. Included are a series of naturally occurring minerals, synthetic salts, and precipitated hydroxyapatites. Highly substituted apatites such as FrancoHte, Ca2Q(PO (C02) (F,0H)2, are the principal component of phosphate rock used for the production of both wet-process and furnace-process phosphoric acid. [Pg.334]

Weaker complex ions may also form with orthophosphates, eg, CaH2PO" 4 in mildly acidic solutions of calcium phosphates, and FeHPO" 4 as a colorless species in impure phosphoric acid. Anionic complexes such as Fe(HPO 2 o known. [Pg.340]

Tricalcium Phosphate. Commercial tricalcium phosphate (TCP) is actually an amorphous basic calcium phosphate close to hydroxyapatite in composition. Because of its extremely low solubiUty in water, TCP is precipitated almost quantitatively from dilute phosphate solutions with a slurry of hydrated lime. TCP is separated by dmm-, spray-, or flash-drying the TCP slurry, with or without intermediate sedimentation or filtration steps. It is used as an industrial-grade flow conditioner and parting agent. [Pg.342]

U.S. consumption of industrial-grade phosphoric acid and phosphates in 1993 according to product categories (34) was phosphoric acid, at 29% sodium phosphate, 52% calcium phosphate, 7% potassium phosphate, 3% ammonium phosphate, 5% and others, 4%. Consumption according to market is given in Table 12. [Pg.344]

The largest-volume phosphoms compounds are the phosphoric acids and phosphates (qv), ie, the oxide derivatives of phosphoms ia the + 5 oxidation state. With the exception of the phosphoric acid anhydride, P O q, and the phosphate esters, these materials are discussed elsewhere (see Phosphoric acids and phosphates). An overview of phosphoms compounds other than the phosphoric acids and phosphates is given herein. These compounds constitute a large variety of phosphoms compounds that are either nonoxide derivatives or derivatives of phosphoms ia oxidation states lower than + 5. These phosphoms compounds are manufactured only from elemental phosphoms (qv) obtained by reduction of naturally occurring phosphate rock (calcium phosphate). [Pg.356]

Urea resin adhesives, by the use of the proper hardener, may be set either by heat or at room temperature. For room temperature curing, the hardener may be ammonium chloride, together with basic materials like calcium phosphate to neutralize excess acid that might damage the wood. Cold set or room temperature set adhesives are those that set satisfactorily at 20 —30°C, whereas a hot set adhesive generally means one that is set above 99 °C. [Pg.326]

Bioglasses are surface-active ceramics that can induce a direct chemical bond between an implant and the surrounding tissue. One example is 45S5 bioglass, which consists of 45% Si02, 6% 4.5% CaO, and 24.5% Na20. The various calcium phosphates have exceUent compatibUity with bone and... [Pg.176]

Hydroxyapatite (HA) coating on the surface of the hip stem and the acetabular cup is the most recent advancement in artificial hip joint implant technology. This substance is a form of calcium phosphate, which is sprayed onto the hip implant. It is a material found in combination with calcium carbonate in bone tissue, and bones can easily adapt to it. When bone tissue does grow into HA, the tissue then fixes the hip joint implant permanently in position. These HA coatings are only used in press-fit, noncemented implants. [Pg.188]


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Absorption of Calcium and Phosphate

Acid calcium phosphate

Adsorption and Elution on Calcium Phosphate Gel

Amorphous calcium phosphate

Amorphous calcium phosphate biomineralization

Anhydrous calcium hydrogen phosphate

Anhydrous dibasic calcium phosphate

Bioactive glass calcium phosphate ceramics

Bioceramics calcium-phosphate ceramics

Biological calcium phosphate

Biomimetic Calcium Phosphate Coatings Deposited on Various Substrates

Biomimetic calcium phosphate biocompatibility

Biomimetic calcium phosphate coatings

Biomimetic calcium phosphate poly

Biphasic calcium phosphate

Bone graft substitutes calcium phosphate cement

Bone treatment with calcium phosphates

Buffering capacity soluble calcium phosphate

Calcium Phosphate Cements with Biomedical Applications

Calcium Phosphate, Hydroxyapatite, and Poly(d,-lactic acid)

Calcium Phosphate-Based Materials

Calcium VAPOL phosphate

Calcium X phosphate product

Calcium acetate 583 arsenate phosphate

Calcium carbonate phosphate

Calcium carbonate phosphate compounds

Calcium carbonate phosphatic particles

Calcium caseinate phosphate complex

Calcium dihydrogen phosphate

Calcium hydrogen phosphate

Calcium hydrogen phosphate CaHPO

Calcium hydrogen phosphate dihydrate

Calcium hydroxide phosphate

Calcium inositol phosphate effects

Calcium ions phosphate ester hydrolysis

Calcium magnesium phosphate

Calcium magnesium phosphate, fused

Calcium monohydrogen phosphate

Calcium monohydrogen phosphate dihydrate

Calcium phosphate adsorption and

Calcium phosphate amino acid composition

Calcium phosphate and

Calcium phosphate bone cements

Calcium phosphate capacity

Calcium phosphate casein interactions

Calcium phosphate cements

Calcium phosphate ceramics, phases

Calcium phosphate chemical characterization

Calcium phosphate cleaning

Calcium phosphate coatings

Calcium phosphate composites

Calcium phosphate composites with

Calcium phosphate deposition

Calcium phosphate dibasic dihydrate

Calcium phosphate dihydrate

Calcium phosphate elution from

Calcium phosphate fluorides

Calcium phosphate formation

Calcium phosphate gels and

Calcium phosphate granules

Calcium phosphate inhibition

Calcium phosphate matrix

Calcium phosphate method

Calcium phosphate micellar

Calcium phosphate minerals

Calcium phosphate nanoparticles

Calcium phosphate pastes

Calcium phosphate phases

Calcium phosphate physical characterization

Calcium phosphate precipitates

Calcium phosphate precipitation

Calcium phosphate protein chromatography

Calcium phosphate regeneration

Calcium phosphate ripening

Calcium phosphate scaffold

Calcium phosphate scale

Calcium phosphate scale deposition

Calcium phosphate solubility in water

Calcium phosphate solubility product

Calcium phosphate soluble glasses

Calcium phosphate stability

Calcium phosphate sulfuric acid reaction with

Calcium phosphate technique

Calcium phosphate thermal conductivity

Calcium phosphate transfection

Calcium phosphate transformation

Calcium phosphate, bioceramic applications

Calcium phosphate, coprecipitation

Calcium phosphate, mineralization

Calcium phosphate, molar solubility

Calcium phosphate, scaling

Calcium phosphate, scaling control

Calcium phosphate-based nanocomposites

Calcium phosphate-based system

Calcium phosphate-coated

Calcium phosphate-coated nanoparticles

Calcium phosphate-polymer

Calcium phosphate-polymer nanocomposites

Calcium phosphate-silicates

Calcium phosphate-silicates solubilities

Calcium phosphate/chitosan

Calcium phosphates PHEMA) hydrogels

Calcium phosphates bioactive glass

Calcium phosphates growth

Calcium silicate-phosphates, preparation

Calcium sodium phosphate

Calcium strontium phosphate

Calcium uranium phosphate

Calcium-Titanium-Zirconium Phosphates

Calcium-phosphate ceramics

Calcium-phosphate product

Calcium: phosphate ratios

Casein micelle calcium phosphate

Casein micelles phosphate—calcium fractions

Cements, calcium phosphate-based

Chemistry of Calcium Phosphates

Chiral calcium phosphate

Colloidal calcium phosphate

Colloidal calcium phosphate association with casein

Colloidal calcium phosphate solubilization

Crystallization experiments, calcium phosphates

Dibasic calcium phosphate

Diluents calcium phosphate

Electrochemical calcium phosphate coating

Electrophoretic Deposition of Calcium Phosphate Coatings

Fluorine calcium phosphate precipitation

Functional calcium phosphate ceramics

Glass, calcium phosphate

Growth rates calcium phosphates

Hard tissues, calcium phosphate

Hyaluronic Acid Carriers with Calcium Phosphate Particles

Hydroxyapatite calcium phosphate precipitation

Inorganic calcium phosphate

Inositol phosphate calcium regulation

Interference calcium-phosphate

Liquid amorphous calcium phosphates

Mineralization calcium phosphate precipitation

Monobasic calcium phosphate

Nano-hybrids Combined with Calcium Phosphates

Nanoclusters, calcium phosphate

Nanocrystalline calcium phosphates

Osseointegration calcium phosphates

Oxalate calcium phosphate deposition

Parenteral nutrition calcium phosphate precipitation

Phosphate binders calcium-based

Phosphate calcium balance

Phosphate calcium phosphorus product

Phosphate metabolism, calcium link

Phosphate onto calcium carbonate

Phosphate stabilization calcium minerals

Phosphates, modified calcium

Plasma Concentrations of Calcium and Phosphate

Polymer-coated calcium phosphate

Polymer-coated calcium phosphate nanoparticles

Porous calcium phosphates

Precipitated Calcium Phosphate

Precipitation kinetics calcium phosphates

Primary calcium phosphate

Resorbable Calcium Phosphate Ceramics

Salts calcium phosphates

Secondary calcium phosphate

Sodium Calcium Phosphate Fibers

Solubility calcium phosphates

Stability of Nano-Calcium Phosphates

Structure and Transformation of Amorphous Calcium Phosphate (ACP)

Sulfuric acid with calcium phosphate

Supersaturation, calcium phosphate

Supersaturation, calcium phosphate solutions

Synthesis nano-calcium phosphates

Synthesis of Nano-Calcium Phosphates

Tertiary calcium phosphate

The Absorption of Calcium and Phosphate

Tri-calcium phosphate

Tribasic calcium phosphate

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