WO1996010536A1 - Method for making phosphated alkaline salts, resulting salts and silicas, and detergent or foodstuff containing such salts - Google Patents
Method for making phosphated alkaline salts, resulting salts and silicas, and detergent or foodstuff containing such salts Download PDFInfo
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- WO1996010536A1 WO1996010536A1 PCT/BE1994/000065 BE9400065W WO9610536A1 WO 1996010536 A1 WO1996010536 A1 WO 1996010536A1 BE 9400065 W BE9400065 W BE 9400065W WO 9610536 A1 WO9610536 A1 WO 9610536A1
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- silica
- phosphoric acid
- silicate
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
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- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23L—FOODS, FOODSTUFFS, OR NON-ALCOHOLIC BEVERAGES, NOT COVERED BY SUBCLASSES A21D OR A23B-A23J; THEIR PREPARATION OR TREATMENT, e.g. COOKING, MODIFICATION OF NUTRITIVE QUALITIES, PHYSICAL TREATMENT; PRESERVATION OF FOODS OR FOODSTUFFS, IN GENERAL
- A23L29/00—Foods or foodstuffs containing additives; Preparation or treatment thereof
- A23L29/015—Inorganic compounds
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/30—Alkali metal phosphates
- C01B25/301—Preparation from liquid orthophosphoric acid or from an acid solution or suspension of orthophosphates
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- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/38—Condensed phosphates
- C01B25/40—Polyphosphates
- C01B25/41—Polyphosphates of alkali metals
- C01B25/412—Preparation from alkali metal orthophosphates
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- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/14—Colloidal silica, e.g. dispersions, gels, sols
- C01B33/152—Preparation of hydrogels
- C01B33/154—Preparation of hydrogels by acidic treatment of aqueous silicate solutions
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- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/18—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof
- C01B33/187—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by acidic treatment of silicates
- C01B33/193—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by acidic treatment of silicates of aqueous solutions of silicates
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- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/02—Inorganic compounds ; Elemental compounds
- C11D3/04—Water-soluble compounds
- C11D3/06—Phosphates, including polyphosphates
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- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/02—Inorganic compounds ; Elemental compounds
- C11D3/04—Water-soluble compounds
- C11D3/06—Phosphates, including polyphosphates
- C11D3/062—Special methods concerning phosphates
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- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
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- C01P2004/60—Particles characterised by their size
- C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
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- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
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- C01P2006/19—Oil-absorption capacity, e.g. DBP values
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- C01P2006/62—L* (lightness axis)
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- C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
- C01P2006/63—Optical properties, e.g. expressed in CIELAB-values a* (red-green axis)
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- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
- C01P2006/64—Optical properties, e.g. expressed in CIELAB-values b* (yellow-blue axis)
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Definitions
- the present invention relates to a process for the production of high purity phosphatic alkaline salt, in particular a tripolyphosphate, such as sodium tripolyphosphate meeting the purity requirements of the detergency industry from phosphoric acid obtained. wet.
- a tripolyphosphate such as sodium tripolyphosphate meeting the purity requirements of the detergency industry from phosphoric acid obtained. wet.
- the known processes for the manufacture of such a salt are characterized by the precipitation of the impurities provided by phosphoric acid during the partial neutralization of this acid by means of sodium hydroxide, the elimination , by filtration, phosphates of the various metals constituting the impurities and the recovery of a purified sodium phosphate solution.
- Belgian Patent No. 869,169 from the company Pelt & Hooykaas describes a process treating the filter cakes recovered during the purification of the liquors used to produce sodium tripolyphosphate.
- This process consists in drying and calcining the residue in the presence of a mineral flux which can either be a metallurgical slag, or the residue itself previously calcined and melted.
- a mineral flux which can either be a metallurgical slag, or the residue itself previously calcined and melted.
- This calcination which takes place at a temperature between 700 and 1300 ° C., makes it possible to eliminate the organic compounds, to reduce the volume and form an open landfill without the risk of pollutants such as heavy metals being leached from storage.
- This residue can also be ground to be used as a road base.
- the F / Mg ratio is adjusted to 1 by adding alkaline fluorides.
- magnesium compounds precipitate and are easily recovered by filtration, which makes it possible to obtain solutions making it possible to produce a sodium tripolyphosphate whose magnesium content satisfies the requirements of detergency.
- the acid to be purified is brought into contact with a nonaqueous solvent to give an organic phase rich in H 3 P0 4 .
- This organic phase is brought into contact with an alkaline aqueous sodium phase (Na 2 C0 3 or Na 2 HC0 3 or NaOH) so that a part, for example from 15 to 35%, of the phosphoric acid is transformed into corresponding sodium salts.
- the organic phase is reextracted with water.
- the aqueous phase thus produced is adjusted to a pH of between 4 and 6 with NaOH in order to precipitate the polyvalent ions.
- the precipitate is removed by filtration and the residual solution is adjusted to pH 8 with NaOH in order to produce sodium tripolyphosphate.
- the iron By neutralizing at least the first proton of H 3 PO 4 of a phosphoric acid containing 50 to 500 ppm of Fe relative to P 2 0 5 by 1 to 50 kg of lime of which at least 75% is below 10 ⁇ m , the iron can be precipitated in such a way that the 10 to 50 ppm of Fe remaining in solution can no longer constitute a deactivator of the perborate bleach which is also added to the detergent with sodium tripolyphosphate.
- Document BR-9304577 from the company SERANA describes an integrated process for purifying phosphoric acid by precipitation of impurities for the manufacture of detergent. By partial neutralization of the acid, the process makes it possible to remove, by precipitation, contaminants such as Fe, Al, F, SO 4 and Mg.
- sodium phosphate solutions containing 45% P 2 0 5 , and less than 0.15% F, 22 ppm Mg, 40 ppm S0 4 , 40 ppm Fe, 10 ppm Al can be produced.
- These solutions are of sufficient quality to produce sodium phosphates of technical quality, such as, for example, sodium tripoly ⁇ phosphate for use in detergency.
- the present invention relates to a process for the manufacture of alkaline phosphates (Li, Na, K) of technical or food quality with a low content of metallic impurities, for example titanium and iron, from phosphoric acids which may contain up to at 100 ppm of these impurities.
- the process according to the invention comprises the reaction of phosphoric acid with an aqueous solution of an alkali silicate, such as a sodium, potassium or lithium silicate, so as to form , on the one hand, a solution of the corresponding phosphate salt and, on the other hand, of micro-amorphous silica retaining the impurities contained in the phosphoric acid used, the phosphate salt and the silica obtained then being separated one of the other.
- an alkali silicate such as a sodium, potassium or lithium silicate
- alkaline silicate as a source of the alkali metal makes it possible to obtain significant chemical purification, despite the fact that the alkali silicate can contain up to 100 ppm of titanium, while the corresponding hydroxide is practically free of it.
- the siliceous product obtained met, after drying, the most stringent requirements as to its use as precipitated silica or as silica gel.
- the process for manufacturing the alkaline phosphate salt according to the invention therefore also makes it possible to solve a serious environmental problem created by the factories for manufacturing such micro-amorphous silicas.
- the process according to the invention is especially useful for the manufacture of sodium phosphate and in particular sodium tripolyphosphate, it is also advantageous for the manufacture of phos- phates of other alkali metals.
- this process allows the manufacture of dilute potassium phosphate solutions which are capable, after concentration and possibly adjustment of the pH using potassium hydroxide, of producing phosphates or technical and food grade potassium pyrophosphates while maintaining the quality of the co-produced silica.
- the silicas which are obtained as co-products are of the micro-amorphous or non-crystalline type and are essentially characterized by very high specific surfaces between 10 and 800 m 2 / g as well as by extremely porous degrees. high, as evidenced by the low apparent densities.
- These micro-amorphous solids whose general physico-chemical properties and the main formation mechanisms are described in the work of ILER (The Chemistry of Silica, John Wiley, 1979), are composed of primary colloidal particles of nanosize metrics which, by coagulation, gave rise to a gel or a precipitate.
- the process according to the invention consists in reacting with phosphoric acid an alkaline silicate in the form of an aqueous solution whose molar ratio Si0 2 / M 2 0
- reaction products obtained are formed, on the one hand, of an alkaline phosphate salt in solution and, on the other hand, of silica which can be in a precipitated form or in the form of a gel.
- reaction products are then separated from each other and, if necessary, subjected to different treatments according to the applications envisaged.
- the chemical composition of the phosphate solution obtained, as well as the physicochemical characteristics of the siliceous product depend on many operating variables: dilutions of the phosphoric acid and silicate solutions, order and speed of addition of said solutions, their temperature , the molar ratios Si0 2 / M 2 0 and P 2 0, / M 2 0, the stirring of the reactor, etc., M being Na, K or Li.
- the reaction is advantageously carried out in a stirred batch reactor.
- the working method described below is particularly favorable because it provides easily recoverable silica precipitates on an industrial scale. Their good filterability allows, in fact, an easy separation of the solid and the phosphate solution.
- the final physicochemical properties of these silicas provide them with excellent performance in various fields of application.
- the total quantity of sodium silicate necessary for the reaction is introduced beforehand into the reactor in the form of an aqueous solution at a weight concentration of Si0 2 which is advantageously between 6 and 12%.
- a solution of phosphoric acid is added thereto progressively, the H 3 PO 4 titer is preferably between 30 and 50%.
- the acid feed rate is one of the operating variables.
- the reaction mixture is stirred throughout the addition.
- the amount of phosphoric acid added depends in particular on the M / P ratio of the sodium phosphate sought.
- the final H 3 P0 4 / M 2 0 molar ratio will however be greater than 0.80, so that the aqueous phase has a pH less than or equal to 9 when separating the silica. This also applies if the silicate used is a potassium or lithium silicate.
- Different techniques may be suitable for separating precipitated silica from phosphated mother liquors, such as, for example, vacuum or filter press filtration methods.
- a washing step for example by supplying fresh water, can be useful to guarantee an optimal phosphate yield.
- the relatively dilute sodium phosphate filtrate is then reconcentrated, for example using a multiple-effect evaporator.
- the filter cake, containing the precipitated silica can be dried by various common methods, the choice of the dryer being largely dictated by the physical presentation of the desired finished product.
- the most suitable devices there are trays dryers, flash dryers and air towers.
- This type of device is particularly advantageous because it directly supplies a finished product in the form of microbeads, the main properties of which are their excellent fluidity and their non-pulverulent nature, and this without requiring any further treatment, as is the case. other drying processes.
- the proposed method for producing silica gels from alkali silicate and phosphoric acid also presents several variants. The main process steps are described below. We start by neutralizing the silicate in aqueous solution by reaction with phosphoric acid so as to form a colloidal solution. One of the operating variables is the generally acidic pH of the reaction mixture. This mixing operation is carried out in a stirred reactor. The hydrosol thus obtained is then kept at rest for the time necessary to transform it into a hydrogel.
- One of the possible methods is the rapid gelation method, which consists in mixing silicate and phosphoric acid continuously using a sprayer placed above a conveyor belt, the reaction conditions being chosen so as to that the gelling process is almost instantaneous.
- the gel is then shaped, washed with water to extract the phosphate salt therefrom, and finally dried. Washing with water is carried out for example in a counter-current reactor.
- the final density of the gel also largely depends on the drying process used. Flash-type drying, for example, provides less dense gels, characterized by larger pore sizes, than the same, more slowly dried silicas.
- STPP sodium tripolyphosphate
- the general physicochemical characteristics of the silicas obtained are listed below. It is obviously possible to modulate these properties and to adapt them to the specificities of each field of application by optimizing the reaction conditions between the silicate and the phosphoric acid or by modifying the post-treatments which one inflicts on the silica after separation of the phosphate solution.
- the residual moisture in the silica is made up of two different types of water.
- the weight loss at 105 ° C indicates the "free water” content. This can be easily adjusted by adjusting the operating conditions of the dryer.
- the weight loss at 1000 ° C of the silica which will be expressed relative to the dried product at 105 ° C, is between 3 and 8% and reflects, for its part, the "bound water” content of the silica.
- the structure in the form of porous and open aggregates which characterizes the precipitated silicas according to the invention generally results in very low apparent densities.
- This physical structure also gives them a remarkable absorption power, as shown for example by the dibutylphthalate absorption test (DBP).
- DBP dibutylphthalate absorption test
- This measurement is carried out in accordance with standard NF ISO 4656/1.
- the DBP intakes thus measured are between 50 and 300 g of DBP per 100 g of silica according to the operating conditions adopted during the precipitation of the silica.
- the particle size characteristics of the silicas obtained vary according to the drying and final shaping processes used.
- precipitated silica dried by a "flash" process for example, it has been observed that the average size of the particles obtained is around 15 ⁇ m and that the rejection on a sieve 40 ⁇ m, measured according to the sieving method ISO 787/18 wet, does not exceed 0.2% after ultrasonic dispersion.
- the Si0 2 content of the silica determined by gravimetry and expressed relative to the dry product at 105 ° C., essentially depends on the degree of washing achieved during the separation. Weight contents of Si0 2 of more than 93% are easily obtained.
- the acidity of the silica depends on the H 3 P0 4 / M 2 0 ratio.
- a correction of pH by addition of acid or alkali after the separation of the phosphate solution is however possible.
- a separation around pH 7 is particularly favorable, since, on the one hand, this pH practically corresponds to that of sodium tripolyphosphate and, on the other hand, the pH of the silica thus obtained is compatible with the majority of applications. - tions, any acidity correction is therefore superfluous.
- Example 1 The sodium silicate in the starting solution had a Si0 2 / Na 2 0 molar ratio of 3.32 and titrated 35.8% of dry matter. It was a solution of industrial origin of current quality whose iron, aluminum and titanium contents were respectively 50, 160 and 50 ppm.
- the sodium silicate solution was first diluted by adding demineralized water to a weight concentration of SiO 2 of 8.0%. After having brought 2649 kg of this diluted solution to a well-stirred reactor and having raised its temperature to 73 ° C by an indirect heating system, the feeding of phosphoric acid could begin. This solution was supplied with an H 3 P0 4 concentration of 45%, the titer adjustment also being made. by adding demineralized water. The reaction mixture was stirred throughout the acidification. After an hour and a half of reaction, the temperature was brought to 85 ° C. After three hours, the volume of solution supplied reached 475 1. Next, the suspension obtained, the pH of which measured at the temperature indicated above was close to 7.0, was cooled to 60 ° C, then filtered and washed on filter press.
- the filter cake containing the silica was reliquified by mechanical stirring before being dried in an atomization tower.
- the pH of the product was adjusted by a small addition of phos ⁇ phoric acid before drying.
- the final precipitated silica was in the form of microbeads and had the following characteristics: BET surface (m 2 / g) 172
- CTAB area 160 DBP absorption (g / lOOg) 250
- Example 2 The precipitation reaction was carried out under operating conditions identical to those of Example 1, except that the addition of phosphoric acid ended at pH 8.0. The mixed filtrates then reached an Na / P ratio of 2.05, which was then adjusted to that of disodium phosphate by adding phosphoric acid. The anhydrous disodium phosphate that we prepared from this corrected solution had the following characteristics: P 2 0 5 (%) 49.9
- the filter cake was subjected to a fairly large pH correction by adding phosphoric acid, followed by a second washing with water to remove the excess salt formed during this adjustment.
- the characteristics of the precipitated silica obtained at the outlet of the atomizing dryer were practically identical to those of Example 1.
- Example 3 The precipitation reaction was carried out under operating conditions identical to those of Example 1, except that the addition of phosphoric acid was terminated at pH 5.8. The mixed filtrates then reached an Na / P ratio of 1.21, which was adjusted to that of monosodium phosphate by addition of phosphoric acid. Anhydrous sodium phosphate prepared from this phosphate solution had the following characteristics: P 2 0 5 (%) 59.1
- Example 4 The filter cake obtained according to the procedure of Example 1 was dried using a flash dryer.
- CTAB area (m 2 / g) 158 DBP absorption (g / 100g) 245
- CTAB area (m / g) 106 DBP absorption (g / 100 g) 205
- Example 6 The raw materials were practically of the same purity as those of Example 1. 1567 g of silicate diluted with 6.38% of Si0 2 were rapidly mixed with 933 g of acid titrating 10% of H 3 P0 4 . This operation was carried out in a vigorously agitated berlin, after which the reaction mixture was kept at rest. The Si0 2 concentration there was 4.0% and the pH there reached 5.2. After half an hour, the hydrogel formed was fragmented by mechanical stirring in the berlin, where it then underwent several successive washes with demineralized water, the water used for the last washing being very slightly basic so as to neutralize the suspension. The gel was finally dried in an oven at 105 ° C.
- the sodium phosphate of the filtrate was at an Na / P ratio of 1.05, finally adjusted to that of the sodium phosphate by addition of phosphoric acid.
- the anhydrous monosodium phosphate which was prepared from this phosphate solution had the following characteristics: P 2 0 5 (%) 59.0
- Example 7 The method was the same as that of Example 6, except that the last step of washing the gel was carried out with an ammonia solution at pH 9 and that the gel thus washed underwent another time of maturation. one hour before drying.
- the analysis of sodium phosphate was practically identical to that of the previous example.
- the physical structure of the silica gel obtained was greatly modified: BET surface (m 2 / g) 360
- Example 8 The method of Example 3 was applied to the case of potassium silicate.
- the iron, aluminum and titanium contents of the potassium silicate used were relatively equivalent to those of the preceding sodium silicate and the molar ratio Si0 2 / K 2 0 chosen was identical to the Si0 2 / Na 2 0 ratio of Example 3. L analysis of the monopotassium phosphate obtained was this:
- the silicas obtained as co-products of the purification process according to the invention have in particular the characteristics required to serve as a reinforcing filler in certain elasto ers.
- the silicas in question give them, in effect, high-performance mechanical properties while considerably increasing their resistance to wear.
- the fields of application of precipitated silicas are numerous.
- the reinforcement of the rubbers mentioned above the fluidification and the anti-caking effect ("anti-caking") on many pulverulent materials, the absorption or placing on the support of liquid active ingredients. des, the improvement of the whiteness and opacity of emulsion papers and paints, the use of the thickening and pseudo-plastic power of these silicas in toothpastes, as well as in certain cleaning products.
- the silicas resulting from the present invention can also be used to structure the excessively smooth surfaces of certain plastic films, papers, coatings or paints. Silica then plays an anti-blocking or anti-slip role, or possibly acts as a matting agent. The apti- Study in printing or impregnation can also be improved by these silicas.
- silica gels are also numerous. They are often used as an absorbent, and in particular as a desiccant when the absorbed substance is water. A second equally important sector of application is that of coatings, where silica gels are used mainly as a matting agent. Furthermore, silica gels also have certain fields of application in common with precipitated silicas, such as for example the fluidification and the anti-caking effect of powders, and the function of anti-blocking in certain plastic films. Other uses, such as supported catalysts and the packing of chromatographic columns are however reserved for gels.
- the potassium and sodium salts find their application both as adjuvants in detergents and in agriculture and the food industry.
- an essential advantage of the process according to the invention is that it makes it possible to obtain two reaction products which, thanks to their purity, find many industrial applications, unlike which is the case with conventional processes which give, in addition, alkaline phosphated salt, a non-recoverable residue.
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Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/BE1994/000065 WO1996010536A1 (en) | 1994-10-03 | 1994-10-03 | Method for making phosphated alkaline salts, resulting salts and silicas, and detergent or foodstuff containing such salts |
EP94927463A EP0784594A1 (en) | 1994-10-03 | 1994-10-03 | Method for making phosphated alkaline salts, resulting salts and silicas, and detergent or foodstuff containing such salts |
MA24021A MA23675A1 (en) | 1994-10-03 | 1995-09-28 | PROCESS FOR THE MANUFACTURE OF HIGH PURITY ALKALINE PHOSPHATE SALTS, SALTS AND SILICAS OBTAINED, AS WELL AS DETERGENT OR FOOD PRODUCT CONTAINING THIS SALT |
TNTNSN95100A TNSN95100A1 (en) | 1994-10-03 | 1995-10-02 | PROCESS FOR THE MANUFACTURE OF HIGH PURITY ALKALINE PHOSPHATE SALTS, SALTS AND SILICAS OBTAINED, AS WELL AS DETERGENT OR FOOD PRODUCT CONTAINING THIS SALT |
IL11548195A IL115481A0 (en) | 1994-10-03 | 1995-10-02 | Process for the manufacture of alkali metal phosphate salts of high purity salts and silicas obtained and detergent or alimentary product containing this salt |
TR95/01208A TR199501208A2 (en) | 1994-10-03 | 1995-10-03 | The method of manufacturing high purity phosphate alkali salts, salts and silicas obtained, as well as detergents or food products containing these salts. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/BE1994/000065 WO1996010536A1 (en) | 1994-10-03 | 1994-10-03 | Method for making phosphated alkaline salts, resulting salts and silicas, and detergent or foodstuff containing such salts |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996010536A1 true WO1996010536A1 (en) | 1996-04-11 |
Family
ID=3887898
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/BE1994/000065 WO1996010536A1 (en) | 1994-10-03 | 1994-10-03 | Method for making phosphated alkaline salts, resulting salts and silicas, and detergent or foodstuff containing such salts |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0784594A1 (en) |
IL (1) | IL115481A0 (en) |
MA (1) | MA23675A1 (en) |
TN (1) | TNSN95100A1 (en) |
TR (1) | TR199501208A2 (en) |
WO (1) | WO1996010536A1 (en) |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1078134A (en) * | 1952-06-13 | 1954-11-16 | Degussa | Process for preparing highly divided powder silica |
FR1134178A (en) * | 1954-11-05 | 1957-04-08 | Columbia Southern Chem Corp | Improvements with siliceous pigments |
FR2159580A5 (en) * | 1971-11-04 | 1973-06-22 | Sifrance | |
FR2272033A1 (en) * | 1974-05-22 | 1975-12-19 | Sifrance | |
JPS601115A (en) * | 1983-06-16 | 1985-01-07 | Central Glass Co Ltd | Amorphous silica for transparent dentifrice and its production |
JPS62113713A (en) * | 1985-11-14 | 1987-05-25 | Osaka Soda Co Ltd | Production of silica gel |
-
1994
- 1994-10-03 EP EP94927463A patent/EP0784594A1/en not_active Ceased
- 1994-10-03 WO PCT/BE1994/000065 patent/WO1996010536A1/en not_active Application Discontinuation
-
1995
- 1995-09-28 MA MA24021A patent/MA23675A1/en unknown
- 1995-10-02 TN TNTNSN95100A patent/TNSN95100A1/en unknown
- 1995-10-02 IL IL11548195A patent/IL115481A0/en unknown
- 1995-10-03 TR TR95/01208A patent/TR199501208A2/en unknown
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1078134A (en) * | 1952-06-13 | 1954-11-16 | Degussa | Process for preparing highly divided powder silica |
FR1134178A (en) * | 1954-11-05 | 1957-04-08 | Columbia Southern Chem Corp | Improvements with siliceous pigments |
FR2159580A5 (en) * | 1971-11-04 | 1973-06-22 | Sifrance | |
FR2272033A1 (en) * | 1974-05-22 | 1975-12-19 | Sifrance | |
JPS601115A (en) * | 1983-06-16 | 1985-01-07 | Central Glass Co Ltd | Amorphous silica for transparent dentifrice and its production |
JPS62113713A (en) * | 1985-11-14 | 1987-05-25 | Osaka Soda Co Ltd | Production of silica gel |
Non-Patent Citations (2)
Title |
---|
DATABASE WPI Section Ch Week 0785, Derwent World Patents Index; Class D21, AN 85-041557 * |
PATENT ABSTRACTS OF JAPAN vol. 011, no. 326 (C - 454) 23 October 1987 (1987-10-23) * |
Also Published As
Publication number | Publication date |
---|---|
TNSN95100A1 (en) | 1996-02-06 |
IL115481A0 (en) | 1996-01-19 |
TR199501208A2 (en) | 1996-06-21 |
EP0784594A1 (en) | 1997-07-23 |
MA23675A1 (en) | 1996-04-01 |
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