Fluoride is removed in the preparation of dicalcium phosphate from wet process phosphoric acid by neutralizing the acid with an alkaline compound of calcium, e.g. lime or calcium carbonate, to a pH range 2.9-3.1; removing the precipitate, which is mainly fluoride; and then neutralizing the residual acid to precipitate dicalcium phosphate.
the dicalcium phosphate anhydride powder used in accordance with the invention is distinguished by a particularly high bulk weight and, in spite of the relatively high degree of fineness, by a very good trickle flow characteristic. For that reason this powder is particularly suitable for direct tabletting without preceding granulation and introduces a larger amount of calcium into the ...
A process is disclosed for the production of granulated dicalcium phosphate dihydrate from fine-grained, powered dicalcium phosphate dihydrate, wherein 80 t0 95% of dicalcium phosphate dihydrate with a grain size of less than 120 mu m and 20 to 5% of calcium hydroxide with a grain size of less than 120 mu m are dry mixed and continuously sprayed and granulated in a …
a dicalcium phosphate is prepared in the usual manner by the addition of lime slurry to phosphoric acid, under conditions so that the dicalcium phosphate dihydrated compound is precipitated. After precipitation is complete we add to the mother liquor containing the precipitate a small proportion of alkali metal pyrophosphate, and then heat the slurry to a temperature somewhat above the ...
Compositions containing calcium phosphate and microcrystalline cellulose are useful as excipients in the preparation of solid dosage forms containing active pharmaceutical ingredients, particularly those prepared by processes involving multiple compaction steps. The recompactibility performance of such compositions is improved through the use of calcium phosphate having a …
A stabilized improved dicalcium phosphate dihyabout 04-08% by Weight of a polyphosphoric acid hav- 5 ing at least 40% by weight pyrophosphoric acid, then completing the neutralization of the reaction mixture with the addition of milk of lime until a pH of about 6.9-7.2 is reached, removing and drying the dicalcium phosphate dihydrate formed ...
Anhydrous dicalcium phosphate having an assay of at least 90 percent by weight and composed of particles, a major proportion of which have a particle size of from about 0.1 to 1.0 microns and a specific surface area of at least 10 square meters per gram is prepared by adding well dispersed, substantially dry calcium oxide or calcium hydroxide to phosphoric acid having a …
A granular directly compressible anhydrous dicalcium phosphate having a particle size sufficient for efficient direct compression tableting, preferably at least 90 percent greater than 44 microns, a dentin abrasion value of less than 150 and a surface area of greater than 5 meters 2 /gram can be prepared by dehydrating particles of soft dicalcium phosphate dihydrate of a particle size ...
The other known methods whereby dicalcium phosphate is precipitated by milk of lime, from a solution of phosphate of lime in hydrochloric acld (as in the maceration of bones) or from a solu tion of mineral phosphate in acids, are attended with the disadvantage that the acids used as solvents are entirely lost and that, further, the use of milk ...
A process is disclosed for the production of granulated dicalcium phosphate dihydrate from fine-grained, powered dicalcium phosphate dihydrate, wherein 80 t0 95% of dicalcium phosphate dihydrate with a grain size of less than 120 μm and 20 to 5% of calcium hydroxide with a grain size of less than 120 μm are dry mixed and continuously sprayed and …
the separatedhydrolysis liquidcontaining a high ratio of P205 to iiuorine is treated with such a quantity of a base such as pulverized limestone or hydrated lime that the phosphate contained in the hydrolysissoluvtion is precipitated as dicalciurn phosphate. It has been ascertained that at a pH of about 4.5 most of the phosphate in the solution is precipitated as dicalcium phosphate.
Example 1 100 parts by weight of monosodium phosphate solution having a P O -content of 15.6% were mixed with 19 parts by weight of calcium sulfate dihydrate and 8 parts by weight of calcium hydroxide and treated for 6 hours at temperatures of 20 to 40 C. while agitating with a turbine agitator (5000 r.p.m.) of the Turrax System. The calcium phosphate formed was filtered …
Because calcium hydrogen phosphate is incongruently soluble, it is typically contaminated with various amounts (6-10%) of dicalcium phosphate and free phosphorus acid resulting from in-process disproportionation of the monocalcium salt.
A new and useful method of simultaneously producing and granulating anhydrous dicalcium phosphate is provided. Such a method entails the reaction of concentrated phosphoric acid with a powdered material of lime and/or calcium carbonate in substantially equal stoichiometric amounts, with subsequent, mixing, drying, milling, and sieving to provide the correct target particle size …
the monocalcium phosphate is dissociated by the organic solvent into phosphoric acid and dicalcium phosphate. Since the organic solvent is a relatively good solvent for the phosphoric acid and a relatively poor solvent for the dicalcium phosphate, the dicalcium phosphate and phosphoric acid may be readily separated by well known techniques such as filtration and the like.
This invention relates to a process for the manufacture of feed grade dicalcium phosphate. Dicalcium phosphate known, as DCP is a commonly used animal feed supplement and it is …
DE-A-4 122 960 describes a process for producing coarse-grain dicalcium phosphate anhydride powder, in which at least 95% are of a grain size of over 45 μm and the …
A dentifrice composition is disclosed which contains dicalcium phosphate dihydrate and other common ingredients and a zinc sodium tripolyphosphate compound. ... Priority to US07/425,093 priority Critical patent/US5037636A/en Priority to AU64823/90A priority patent/AU621795B2/en
An eggshell-derived product is utilized as an alternative feed grade calcium and phosphorous source for potential use for all species of livestock. The products is environmentally advantageous and biologically equivalent or superior to currently available commercial products such as feed grade dicalcium phosphate. A method of producing the product elicits monocalcium phosphate …
There is disclosed a process for preparing fertilizers containing dicalcium phosphate from phosphates of mineral origin by mechanical activation. According to the invention grains larger than 5 mm of the sized or unsized starting phosphate compound of mineral origin are granulated up to a grain size of 1 to 4 mm, the granulated phosphate obtained is admixed with …
A process is provided for the production of dicalcium phosphate form a phosphate source material in which a solution of phosphoric acid is produced by the action of a suitable mineral acid, …
A process is disclosed for the production of granulated dicalcium phosphate dihydrate from fine-grained, powered dicalcium phosphate dihydrate, wherein 80 t0 95% of dicalcium phosphate dihydrate with a grain size of less than 120 mu m and 20 to 5% of calcium hydroxide with a grain size of less than 120 mu m are dry mixed and continuously sprayed and granulated in a …
The present invention provides anhydrous dicalcium phosphate particles which satisfies the conflicting requirements of the improvement of handling properties such as high flowability and a small bulk and the improvement of tableting properties at the same time during preparation and a method of producing the same. The method of producing anhydrous dicalcium phosphate by …
U.S. Pat. Nos. 3,919,395 and 4,012,491 have provided processes for the manufacture of dicalcium phosphate using dilute mineral acids to digest a wide range of phosphate rock. …
Priority to PCT/IN2003/000039 priority Critical patent/WO2004076348A1/fr Priority to AU2003303978A priority patent/AU2003303978A1/en ... If required a mixture of mono and dicalcium phosphate may also be produced by adjusting the quantity of hydrated lime. This product is found to have at least 18% or more P than normal ...
The invention relates to dicalcium phosphate anhydride powder, at least 50 wt. % thereof having a particle size of between 45 and 150 μm, a maximum of 50 wt. % having a particle size of <45 μm, and a maximum of 5 wt. % having a particle size of >150 μm. Said powder also exhibits a bulk density of 1000 to 5000 g/l and a specific surface area of <5 m2/g, and is …
Dicalcium phosphate dihydrate, CaHPO4 2H2O, is produced from phosphoric acid and/or a phosphoric acid salt, a calcium compound and, if desired, a basic compound, by a process comprising introducing the calcium compound and the phosphoric acid and/or phosphoric acid salt, in the presence of water, into a reactor, and rapidly and intimately mixing them therein at …
In this work, we developed an injectable drug delivery system based on poloxamer 407 hydrogel containing undoped Mg, Zn-doped tricalcium phosphate (β-TCP), and teicoplanin, a broad …
Dicalcium orthophosphate dihydrate (CaHPO 4 .2H 2 O) that has been stabilized against spontaneous hydrolysis and/or decomposition with a small amount of tetrasodium pyrophosphate in accordance with the processes such as those …
dicalcium phosphate nitrate mass Prior art date Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) ... Priority to US62295411A priority Critical patent/US1011909A/en ...
Rock-derived calcium phosphates such as mono-calcium phosphate (MCP), di-calcium phosphate (DCP) and tri-calcium phosphate (TCP), that are added in pigs and poultry feeds to meet P requirements of these animals, are expensive and non-renewable sources of P. Calcium phosphates of animal origin are potentially cheaper because they are mainly by …
The present invention discloses a method for producing feed grade mono-dicalcium phosphate. The present invention is characterized in that firstly, diluted phosphoric acid and a calcium containing compound carry out the liquid phase neutralizing reaction of step one in a reactor, and calcium biphosphate slurry is generated; then, a calcium containing compound is added into …