84 results about "Urea hydrogen peroxide" patented technology

Compositions are described which are useful in preserving any topically applied solution. Compositions including urea-hydrogen peroxide complex in solution in an amount effective to preserve contact lenses are also described, as well as methods of making and using such solutions. A hydrogen peroxide component of such solutions, when introduced into the eye, is converted to oxygen and water, leaving only the natural product, urea.

The invention belongs to the technical field of the adhesive, and particularly relates to a preparation method of starch base paper packing adhesive, which comprises the steps of mixing, oxidizing and modifying, wherein the mixing step is: water, Urea hydrogen peroxide and starch are added into a reactor to be uniformly mixed, and the mass ratio of the water, the Urea hydrogen peroxide and the starch is: 10 to 16 parts of water, 1 to 4 parts of Urea hydrogen peroxide and 8 to 12 parts of starch; the oxidizing step is: the pH value is adjusted to 8 to 10, catalyst is added to be mixed for 20 to 40 minutes, and then the mixture is statically held for1 to 2 hours; and the modifying step is: modifier and filler are added to be uniformly mixed. The Urea hydrogen peroxide is used as the oxidant of the starch, so not only the production cost is low, the glue consumption quantity is less, but also the production process is free from utilizing defoamer and is free from peculiar smell, and the environmental protection can be realized.

The invention relates to a method for preparing 2,6-dichloro-4-nitroaniline through direct chlorination of chlorine gas and oxidative chlorination of hydrogen peroxide. The method comprises the following steps: (1) adding paranitroaniline into hydrochloric acid at the concentration of 5-35wt%, heating to 40-80 DEG C, stirring for uniformly mixing, slowly inflating the chlorine gas within 0.5-5h, slowly adding hydrogen peroxide dropwise, and after adding the chlorine gas and the hydrogen peroxide, continuing to preserve heat and react for 0.3-1.5h; (2) filtering a product obtained in the step (1), washing a filter cake to be neutral, and drying to obtain the 2,6-dichloro-4-nitroaniline. By regulating a dosage ratio of the chlorine gas to the hydrogen peroxide, the concentration of the hydrochloric acid in a reaction system can be kept unchanged, the reaction process is steady and easily controlled, and the product is high in yield and purity.

The present invention provides a single-component TMB coloration liquid, which is formed by mixing a liquid A and a liquid B, wherein urea hydrogen peroxide is dissolved in a citric acid-sodium citrate buffer liquid to prepare the liquid A, and polyvinyl alcohol, polyvinyl pyrrolidone, TMB and glycerol are dissolved in a citric acid-sodium citrate buffer liquid to prepare the liquid B. Compared with the single-component TMB coloration liquid in the prior art, the single-component TMB coloration liquid of the present invention has the following advantages that: the stability of the coloration substrate in the solution can be maintained, the operator can be protect from being away from organic solvent hazard, the damage on the environment can be reduced, the stable aqueous solution system can be formed, and the single-component TMB coloration liquid can be stored for 24 months at a temperature of 2-8 DEG C.

Provided is a synthetic method for preparing pyridine N-oxide. According to the method, raw materials which are commercialized on the market are selected, or pyridine, monosubstituted pyridine or polysubstituted pyridine derivatives which are easy to prepare are used as starting materials, and the materials are oxidized by urea-hydrogen peroxide compound so to prepare the final product. The advantages of the invention are as follows: 1, the raw materials used in the invention are easily available and cheap and are commercialized or easily preparable raw materials, meeting requirements for large scale production; 2, a safer oxidation method is employed in the invention, thereby avoiding condensation of acetate containing hydrogen peroxide and greatly improving safety factors of production; 3, chemical reaction conditions required in the invention are mild, the operation is simple, little pollution to environment is produced, and the method is technically mature for large scale production.

Disclosed are a method and apparatus with alternate embodiments that use commercial chemical free radical initiators to directly convert methane to methanol in a low energy, one step, catalytic reaction. In one embodiment an apparatus converts “packets” of methane gas to liquid methanol. Methane gas and aqueous hydrogen peroxide are injected into the packet apparatus through valved ports and mixed in a structurally robust, rotating reaction chamber coated with metal cation catalyst. Although operating at low temperature and pressure, the rotating chamber is sufficiently strong enough to contain spontaneous ignition of the mixture should that occur. The reactive oxygen species, primarily hydroxyl radicals, released in the chamber of mildly elevated temperature, oxidize the methane molecule, replacing one hydrogen atom on its molecule with one stable hydroxyl OH molecule, converting vapor methane CH₄ to vapor methanol CH₃OH. Vapor exiting the exhaust port condenses on ambient temperature drip screens to stable liquid methanol. An alternate continuous process embodiment uses flow-through conversion screens coated with immobilized dry chemicals. Water vapor entering the apparatus releases molecular oxygen from screens coated with dry urea hydrogen peroxide. A circulating endless belt screen is used to continual recoat the dry urea hydrogen peroxide. Reactive oxygen species are generated on successive conversion screens through which the molecular oxygen, and methane gas entering the apparatus, must pass. Metal cation catalyst molecules physically entrapped within interstitial cavities of a three dimensional, fixed porous colloidal matrix coating on the screens create powerful hydroxyl radicals from the molecular oxygen. These reactive species in turn convert methane molecules impacting the conversion screens to methanol molecules. The method and apparata operate at modest temperature, pressure, and energy requirement levels, and are scalable from portable units to industrial scale methanol refineries.

The invention relates to soil disinfectant and a method for preventing and treating phytophthora capsici. A raw material of the soil disinfectant comprises the following components: urea-hydrogen peroxide and biogas slurry. The mass ratio of the urea-hydrogen peroxide to biogas slurry is (1-5): (95-99). By the soil disinfectant, the phytophthora capsici in soil can be killed, crops and seedlings can be prevented from being threatened by soil-borne diseases, certain nutrient substances are provided for plant growth, and residues are avoided.

The invention discloses a formula and a production process for preparing methyl ethyl ketazine by utilizing a hydrogen peroxide method, which carries out an in-depth study on the hydrogen peroxide method, thereby improving the hydrogen peroxide method to form a ketazine production method suitable for the situations in China. In the method, hydrogen peroxide is used as an oxidant, ammonia and butanone (methyl ethyl ketone) are used as raw materials and formamide and an inorganic oxide are used as a catalyst and a cocatalyst respectively to interact with each other so as to prepare the ketazine, wherein the hydrogen peroxide belongs to an industrial product and has the concentration of 25% to 30%; ammonia is added in a form of ammonia water with the concentration of 20% to 25%; and the butanone, the formamide and the inorganic oxide are all in the industrial product level. The method disclosed by the invention can be used for solving the problems that the existing initial coarse products for producing hydrazine hydrate are low in concentration, high in energy consumption, low in efficiency and high in cost and the by-products are difficult to treat, thereby being suitable for the situations in China.

A hollow nanosphere used for loading lipase for vanillin preparation through catalytic oxidation is disclosed and relates to the technical field of biological catalysis. The method includes (1) preparing a polymer hollow nanosphere; (2) preparing a polymer-TiO2 composite hollow nanosphere; (3) covering the composite hollow nanosphere with a hard shell; and (4) preparing the disclosed hollow nanosphere. The prepared hollow nanosphere is used for loading the lipase. The lipase loading amount in each gram of the hollow nanosphere is 15 mg or above. A prepared lipase catalyst is specially used for vanillin preparation through catalytic oxidation, coniferyl aldehyde is adopted as a raw material, hydrogen peroxide-urea is adopted as an oxygen source of the lipase, the yield of prepared vanillin is 93% or above, and purity of the prepared vanillin is 98% or above.

The invention discloses a method for preparing epoxidized fatty acid methyl ester through lipase catalysis. The method comprises the following steps of mixing fatty acid methyl ester, organic acid and lipase uniformly according to a mass ratio of 100g:10-30g:3-5g, then adding 10-20g of urea hydrogen peroxide with mass concentration of 25-50% each time for 3-4 times, importing the reaction product into a separator after reacting for 8-10 hours, standing for layering, and drying to obtain the epoxidized fatty acid methyl ester. The method has the advantages of being mild in reaction conditions and environment-friendly, and the like.

A process for removing urea from an aqueous solution is disclosed herein, the process comprises the steps of: feeding an aqueous solution comprising urea into a mix tank; feeding hydrogen peroxide into the mix tank; feeding at least one soluble catalyst into the mix tank separately from the hydrogen peroxide feed; mixing the aqueous solution comprising urea, hydrogen peroxide, and the at least one soluble catalyst in the mix tank, forming a reactant mixture; and oxidizing the urea in the reactant mixture yielding CO₂, N₂, and H₂O. The soluble catalyst is selected from a group of catalysts that when mixed with the hydrogen peroxide and urea causes the rate of reaction of the oxidation of the urea by hydrogen peroxide to accelerate; such as soluble iron salts. A system configured to carry out the process for removing urea from an aqueous solution is also disclosed herein. The disclosed process and system may be added to or incorporated with existing processes and systems for treating aqueous solutions.

The invention provides a hydrogen peroxide-phosphoric acid mixture, and a preparation method and an application thereof. The hydrogen peroxide-phosphoric acid mixture is composed of hydrogen peroxide, phosphoric acid and a stabilizer, a mass ratio of hydrogen peroxide to phosphoric acid is 20:1-50:1, and the stabilizer accounts for 0.1-0.5% of the weight of hydrogen peroxide. The application method of the hydrogen peroxide-phosphoric acid mixture in treatment of cyanogen-containing silvering wastewater comprises the following steps: 1, carrying out electrolyzing pretreatment on the cyanogen-containing silvering wastewater to remove Ag<+> as possible; and 2, treating the pretreated cyanogen-containing silvering wastewater by using the hydrogen peroxide-phosphoric acid mixture. The hydrogen peroxide-phosphoric acid mixture can be used to treat medium and low concentration cyanogen-containing silvering wastewater, and can also be used to treat high concentration cyanogen-containing silvering wastewater. The hydrogen peroxide-phosphoric acid mixture avoids secondary pollution and guarantees the health and safety of operators in the treatment process of the cyanogen-containing silvering wastewater, and allows the precious metal silver to be recovered in the electrolyzing pretreatment process.

The invention provides a bleaching process and device used in the nitric acid preparation process. The bleaching process comprises the following steps of (1) vacuumizing the inside of a nitric acid preparation tank to be at micro negative pressure, (2) leading hydrogen peroxide into a nitric acid solution in the acid preparation tank and performing even mixing to enable the molar ratio of the hydrogen peroxide to NO2 in the acid preparation tank to be higher than 1:2, (3) recovering excessive NO2 from the output end of the acid preparation tank. The bleaching process utilizes compressed air to enable the hydrogen peroxide to be evenly added into the nitric acid solution in the acid preparation tank through a distributor, the hydrogen peroxide reacts with nitrogen dioxide to generate nitric acid and oxygen, and accordingly the nitric acid bleaching purpose is achieved. In addition, excessive nitrogen dioxide escapes and is sucked by a negative pressure pump, so that the nitrogen dioxide content in the acid preparation tank is quickly controlled, and the problem that the nitrogen dioxide content exceeds standard is solved.

The invention provides a catalyst for decomposing hydrogen peroxide. The catalyst for decomposing hydrogen peroxide is characterized by being prepared from, by mass, 1%-30% of VI B-group metal oxide, 1%-20% of IV B-group metal oxide and 50%-98% of III A-group metal oxide. According to a method for decomposing hydrogen peroxide in a product of an epoxidation reaction of 3-chloropropene and hydrogen peroxide by adopting the catalyst, most residual hydrogen peroxide in the product of the reaction can be decomposed before distillation separation, potential hazards of the high hydrogen peroxide content in the product of the epoxidation reaction to the follow-up distillation separation process are effectively eliminated, and therefore the safety of producing epoxy chloropropane through the epoxidation reaction of 3-chloropropene and hydrogen peroxide is improved.

The invention relates to a method for synthesizing vanillin by adopting a bio-enzyme catalytic oxidation method. The method comprises the following steps: sequentially adding a solvent, a primer coniferyl alcohol/coniferyl aldehyde/ferulic acid, lipase, binary acid or a binary acid derivative and urea hydrogen peroxide in a reaction kettle, wherein lipase accounts for 1-4wt% of the primer isoeugenol, the molar mass of the binary acid or the binary acid derivative is 0.75-1.5 times that of the primer; the molar mass of urea hydrogen peroxide is 1-2 times that of the primer, wherein the adding temperature of urea hydrogen peroxide is 15-35 degrees, the reaction temperature is 20-40 degrees and the reaction time is 14-36 hours; filtering, separating and recycling urea and an enzyme-catalyst, diluting the filtrate by water, extracting by using an organic solvent, recrystallizing by edible alcohol and drying to obtain vanillin; and complexing the mother liquor extracted by the organic solvent by virtue of sodium hydrogen sulfite or sodium sulfite to recover the byproduct of aldehyde. The vanillin yield of the method can reach 85% and the method is simple in reaction step, mild in condition, strong in catalytic specificity, hard to generate byproducts, high in product yield, environmentally friendly and easy to amplify.

The invention discloses an aflatoxin enzyme linked immunosorbent assay kit and a detecting method. The aflatoxin enzyme linked immunosorbent assay kit comprises: an enzyme label plate, an aflatoxin B1standard solution, an aflatoxin B1 antibody working solution, an enzyme labeled second antibody working solution, a substrate solution A, a substrate solution B, a stop solution, a concentrated diluent and a concentrated cleaning solution. The substrate solution A is a citric acid-dibasic sodium phosphate buffer solution containing 0.5 mmol/L of hydrogen peroxide urine. The substrate solution B is an ethanol solution of tetramethylbenzidine. The stop solution is 2 mol/L of a sulfuric acid aqueous solution. The enzyme label plate is coated with an aflatoxin B1 coating antigen. The aflatoxin B1coating antigen is obtained by coupling the aflatoxin B1 antigen with bovine serum albumin. Compared with a traditional detecting method, the above detecting method of the kit is relatively simple inboth detecting process and sample processing process, and the detecting process and the operation are both relatively convenient.

A preparation method of a vinpocetine analogue comprises the following steps: using UHP (urea hydrogen peroxide) for selective oxidation of a tabersonine analogue, then performing reduction, rearrangement, crystallization, and the like; or using the UHP for selective oxidation of a tabersonine reduction analogue (vinca-fuming analogue), then performing rearrangement, crystallization, and the like to obtain the vinpocetine analogue. Compared with the prior art, the preparation method has the advantages of high yield, direct quantification, simple operation, mild reaction conditions, suitability for industrial production, the yield reaching over 87%, more than 99% of HPLC (high performance liquid chromatography), a white product, good quality and low preparation cost.

The invention discloses a method of joint production of urea hydrogen peroxide and sodium percarbonate, comprising the following steps: in a material system at the following mass ratio that sodium carbonate: urea: hydrogen peroxide: water is 1:1.30-1.60:0.42-0.45:2.75-3.20, crystallization filtering is carried out at the temperature of 0 DEG C, the obtained solid phase is dried at the temperatureof 60 DEG C to obtain sodium percarbonate, and the residual mother solution S is evaporated and concentrated; and after parts of separated sodium carbonate are evaporated to dryness, urea and hydrogen peroxide of which the mass concentration is 30% are added to ensure that the mass ratio in the system is as follows: sodium carbonate: urea: hydrogen peroxide: water is 1:14.00-16.00:5.50-7.50:14.00-16.50, crystallization filtering is carried out at the temperature of 0 DEG C, the obtained solid phase is urea hydrogen peroxide, and sodium carbonate is added into the liquid phase to ensure that the mass ratio in the system is still as follows: sodium carbonate: urea: hydrogen peroxide: water is 1:1.30-1.60:0.42-0.45:2.75-3.20, and thus cycle production is realized. The invention adopts mild reaction conditions and convenient operation, improves the economy of the urea hydrogen peroxide preparation technology, avoids adverse effect on environment due to mother solution abandonment and lowers production cost.

The invention discloses a method for synchronously synthesizing hydrogen peroxide and peroxyacetic acid, wherein, hydrogen and oxygen are taken as gas sources, alcohol, water and acetic acid are taken as reaction solvent, and phosphoric acid and salt or acid which can generate Br- after being dissolved are taken as reaction assistants; and hydrogen peroxide and peroxyacetic acid can be synthesized synchronously under the conditions that the pressure ranges from 1 to 20 MPa and the temperature ranges from minus 20 to 15 DEG C. The mixed solution that is prepared according to the method can be used as raw material for preparing compound disinfectant and bleaching agents and can also be used as intermediates for other chemical synthesis.