89results about "Phosphorus oxyacids" patented technology

The present invention provides a novel process for producing a calcium phosphate cement or filler which hardens in a temperature dependent fashion in association with an endothermic reaction. In the reaction a limited amount of water is mixed with dry calcium phosphate precursors to produce a hydrated precursor paste. Hardening of the paste occurs rapidly at body temperature and is accompanied by the conversion of one or more of the reactants to poorly crystalline apatitic calcium phosphate. The hardened cements, fillers, growth matrices, orthopedic and delivery devices of the invention are rapidly resorbable and stimulate hard tissue growth and healing. A composite material is provided including a strongly bioresorbable, poorly crystalline apatitic calcium phosphate composite and a supplementary material. The supplementary material is in intimate contact with the hydroxyapatite material in an amount effective to impart a selected characteristic to the composite. The supplemental material may be biocompatible, bioresorbable or non-resorbable. A method for treating a bone defect also is provided by identifying a bone site suitable for receiving an implant, and introducing a strongly resorbable, poorly crystalline apatitic calcium phosphate at the implant site, whereby bone is formed at the implant site. The implant site may be a variety of sites, such as a tooth socket, non-union bone, bone prosthesis, an osteoporotic bone, an intervertebral space, an alveolar ridge or a bone fracture.

Activated carbon is rendered more thermally stable by exposure to a non-halogenated additive, and optionally to a halogen and/or a halogen-containing compound. Such treated carbon is suitable for use in mitigating the content of hazardous substances in flue gases, especially flue gases having a temperature within the range of from about 100° C. to about 420° C.

Carbonate hydroxyapatites containing magnesium, composite materials consisting of said hydroxyapatites and natural polymers are described; processes for the preparation of said materials and their use in orthopaedics and dentistry fields are also described.

A process for purification by multistage countercurrent extraction of wet-process phosphoric acid includes the steps of (a) preparing an aqueous phosphoric acid by decomposition of crude phosphates with sulfuric acid and prepurification thereof; (b) providing an organic solvent mixture consisting of one of (A) a water immiscible solvent and a fully water-miscible solvent or (B) a partially water-miscible solvent and a fully water-miscible solvent; (c) extracting water from the acid by contacting with the solvent mixture in a volumetric ratio of acid to solvent mixture of 1:1 to 1:10 at a temperature of 5 to 90° C.; (d) recovering the fully water-miscible solvent by distillation and washing; (e) recycling the fully water-miscible solvent to step (b) to provide a recycled solvent mixture; and (f) repeating steps (c), (d) and (e) with the recycled solvent mixture to provide a phosphoric acid having a preselected degree of purity.

A phosphorous pentoxide producing method includes forming a kiln bed using feed agglomerates with a calcium-to-silica mole ratio of from 0.5 to 1.0 and maintaining a bed temperature at or above 1260° C. along a portion of the bed length without exceeding 1380° C. along the entire bed length. Less than 10% of the agglomerates' phosphate input to the kiln remains in the kiln residue as phosphate. Another method includes maintaining a bed temperature at or above 1180° C. along a portion of the bed length and establishing a bed surface-to-volume ratio multiplied by a time for bed heat up to 1180° C. of less than 50 minutes-ft²/ft³.

The present invention provides novel indole derivatives useful to inhibit cancer or sensitize cancer cells to chemotherapeutic agents, radiation or other anti-cancer treatments.

The invention relates to a preparing method of difluorophosphoric acid and lithium difluorophosphate. The preparing method of lithium difluorophosphate comprises the following steps of 1, carrying outa reaction between dichloro phosphate and a fluorinated reagent to prepare the difluorophosphoric acid, wherein the fluorinated reagent is AsF3, NH4F, NH4HF2 and/or MFx, for MFx, x is equal to 1 or 2or 3, and M is hydrogen, alkali metal, alkaline-earth metal or transition metal; 2, carrying out a reaction between difluorophosphoric acid and a lithium source material in a non-aqueous agent. According to the preparing method of lithium difluorophosphate, dichloro phosphate, the fluorinated reagent and the lithium source material serve as raw materials to carry out the reactions to prepare lithium difluorophosphate, and the raw materials are wide in source and low in cost; a fluoridation reaction and a substitution reaction of the lithium source material easily take place, the side reactionis small, a crude product of lithium difluorophosphate with few impurities is conveniently obtained under the condition of a high conversion rate, and thus good conditions are created for obtaining high-quality products of lithium difluorophosphate at low cost.

A process and system for recovering waste heat from a kiln used for lime or cement production. The system unifies the kiln, a waste heat recovery and power generation circuit and a dry scrubber for scrubbing the pollutants from the kiln offgas. Essentially, the system employs the boiler component of the waste heat recovery and power generation circuit as a heat exchanger to recover the waste heat from the kiln, which is used to drive the steam turbines. The heat absorption from the latter stage lowers the temperature of the kiln offgas sufficiently for optimum performance from the scrubber. The presence of lime particles in the offgas effectively protects the boiler tube surfaces from corrosion which would occur at optimum scrubber temperatures, and subsequently provides the lime required as a scrubbing medium for the dry scrubber. Further, the efficient scrubbing allows for the use of any fuel for firing the kiln inclusive of high sulphur content compounds. A process for effecting the technology is also provided.

The invention discloses a method for preparing Dawson heteropolyphosphatotungstate. The method comprises the following steps: (1) enabling a tungstate solution to come into contact with an inorganic acid solution, so as to obtain a reactive intermediate; (2) continuously enabling the solution to come into contact with a phosphoric acid solution, so as to obtain a phosphotungstic acid solution; (3) transferring the phosphotungstic acid solution to a high-pressure reactor, and carrying out high-temperature and high-pressure reaction; (4) adding an inorganic salt precipitant to the obtained phosphotungstic acid solution, carrying out salting-out crystallization to obtain phosphotungstate, filtering, purifying and drying, so as to obtain the Dawson heteropolyphosphatotungstate. Compared with the prior art, the method is simple in technological process, short in reaction cycle, high in yield and product purity, and low in cost; meanwhile, strong acid acidification and diethyl ether extraction used in the traditional method are avoided; the safety of the preparation process is greatly improved.

A recycling process is presented to treat spent waste acid solutions whereby useful products are produced. Spent waste acid containing inorganic and organic contaminants is mixed with a magnesium compound containing aluminum and iron compounds that form oxyhydroxide flocs that complex, react, sequester and/or co-precipate the contaminates from the admixture. The magnesium reacts with sulfate ions to form a high quality magnesium sulfate solution.

Provided is an adsorbent for phosphoric acid which can be produced with ease, exhibits high adsorbability of phosphoric acid and is free from any problems in use thereof. The adsorbent for phosphoric acid which includes a water-insoluble reaction product formed by mixing an iron ion and a natural polysaccharide having a carboxylic functional group or a sulfuric acid functional group such as alginate, pectin and carrageenan in a solution, or a dried product thereof. The additional incorporation of a hydrophilic polymer such as agar into the adsorbent prevents the reduction in adsorbability of phosphoric acid in the case where a trivalent iron ion is used to produce the dried product of a water-insoluble reaction product.

The present invention relates to a method of preparing wet process phosphoric acid, which comprises: dividing raw materials which contain phosphate rock slurry and sulfuric acid into two parts, and then feeding these two parts into two reactors separately. In the first reactor, feeding 70–90 wt. % of the total amount of the slurry and sulfuric acid, in which the ratio of phosphate rock slurry to sulfuric acid to recycled phosphoric acid is set to be 1:0.6˜0.8:1.0˜2.5. 10˜30% of the reaction solution directly flows into conversion cell, participating in the conversion reaction of dihydrate gypsum. Thus resulted phosphoric acid concentration is 33˜39 wt. %. The recovery efficiency of P₂O₅ is 99% or more. When putting coke powders in the conversion solution as filter aid, the filtration efficiency can be improved by 10˜30%, and in so produced hemihydrate gypsum, P₂O₅ is 0.05˜0.2%, water of hydration is 4˜8%. The product can be used for producing sulfuric acid and cement without baking dry.

In alternative embodiments, the invention provides processes and methods for the recovery or the removal of the so-called “Minor Elements” consisting of iron, aluminum and magnesium (expressed as oxides), from wet-process phosphoric acid using a continuous ion exchange approach. In alternative embodiments, use of processes and methods of the invention allows for the reduction of these Minor Elements with minimal phosphate losses and dilution in order to produce a phosphoric acid that is suitable for the production of fertilizer products such as world-class diammonium phosphate (DAP), merchant-grade phosphoric acid, superphosphoric acid, and other phosphoric acid products. Further, use of the invention would allow the use of lower grade phosphate rock or ore, which would greatly expand the potential phosphate rock reserve base for phosphate mining activities, and allow for better overall utilization of resources from a given developed mine site.

The present invention provides a class of heteropolyacid loaded mesoporous molecular sieve SBA-15 catalysts and a preparation method thereof, and applications of the catalysts in oxidation of benzene into phenol. According to the present invention, the catalyst adopts the mesoporous molecular sieve SBA-15 is adopted as the carrier, and the Keggin type heteropolyacid H5PMo10V2O40 is loaded on the mesoporous molecular sieve SBA-15 by using the sol-gel method to prepare the catalyst; and in the oxidation reaction of benzene into phenol, the loaded catalyst has characteristics of high selectivity and good catalyst recycling.

Use and reduction of wastewater or “pond water” created by the wet-process phosphoric acid manufacturing there is created a large amount of wastewater or “pond water” to substantially reduce or eliminate the discharge of pond water with contaminants to the environment. By partially treating pond water with known industry standard processes and using the treated pond water for use as required makeup or cooling water in an electric power generator or any other Industry requiring makeup, cooling or process water will substantially reduce or eliminate the need for the phosphoric acid manufacturers to discharge the contaminated water to the environment and reduce the quantity of fresh water that would normally be required by these other industries using the treated pond water for cooling or makeup water.

The present disclosure is directed to a filter support having a surface with a plurality of perforations therein. At least one spray bar may be substantially fixed adjacent to the surface of the filter support. A spray bar may include a plurality of nozzles for directing a pressured fluid toward the filter support. The filter support may further include a motor for causing the filter support to move in a cyclical manner while the spray bar directs pressurized fluid toward the filter support.

The invention belongs to the application field of high polymer materials, and relates to an iron phosphomolybdate smoke suppression PVC plate and a preparation method thereof. The iron phosphomolybdate smoke suppression PVC plate comprises the following components in parts by weight: 100 parts of PVC resin powder, 2-3 parts of a stabilizer, 2-3 parts of a processing aid, 0.5-1 part of a lubricant,3-5 parts of a flexibilizer, 8-15 parts of a filler, and 4-6 parts of a flame-retardant smoke suppressant. According to the iron phosphomolybdate smoke suppression PVC plate provided by the invention, phosphomolybdic acid and ferric hydroxide are used as raw materials, the iron phosphomolybdate prepared by a hydrothermal method is used as a flame-retardant smoke suppressant, and is added to PVC plate production in combination with other additives, the process is simple, the yield is high, and the flame-retardant and smoke-suppression effect is obvious.