62 results about "Ammonium dichromate" patented technology

The invention discloses a method of preparing a chromium-containing ultrafine WC powder through a solid-liquid doping method. The method successively includes the steps of: preparing an ammonium dichromate solution; adding a certain amount of the ammonium dichromate solution to tungsten oxide powder, mixing the components to achieve solid-liquid mixing doping; performing hydrogen reduction, carbon blending, carbonization, cooling, ball milling and sieving to obtain the chromium-containing ultrafine WC powder. The method solves technical problems of non-uniform distribution, large granularity and unsatisfactory effect of inhibiting increase of granularity of WC grains of distribution of Cr3C2 in ultrafine WC powder and hard alloy. When the mixed powder is used for preparing the ultrafine hard alloy, the Cr3C2 has more significant effect of inhibiting the increase of granularity of carbonization grains than a conventional method.

The present invention relates to a preparation method of a safe firing cable of firecrackers. In the method, yarn is used as a carrier to infuse the following medicines, which are used raw materials, according to the following steps. The medicines comprise potassium perchlorate, potassium terephthalic acid, ammonium dichromate, polyethylene alcohol, moisture resistant agent, charcoal and sulfur. The method has the following steps: the potassium perchlorate, the potassium terephthalic acid, the ammonium dichromate, the charcoal, the sulfur and the polyethylene alcohol are arranged in a container according to the weight ratio; water with a certain proportion is added into the container; the mixture is stirred so that the medicines can be dissolved in the water; then the moisture resistant agent is added; and the mixture is mixed well; the yarn is infused in the container, taken out and then sent to a drying device to be dried; thus the safe firing cable can be prepared. In the method, the yarn is used as the carrier to infuse the medicines of the firing cable; the production is simple; the amount of the medicines is reduced; the method is safe; and the cost is reduced. The application of the potassium perchlorate has the advantages of low oxygen content, low decomposition temperature, excellent stability and low sensitivity. Thus the application of the potassium perchlorate is superior to the application of potassium chlorate. The firing cable solves the problems of storage, transportation and insecurity in use.

The invention discloses a method for preparing nanometer WC powder in conditions of low temperature and short process. The method comprises the following steps: taking water soluble ammonium metatungsten and glucose as raw materials, adding ammonium dichromate and ammonium metavanadate which are taken as inhibitors, adding the raw materials and the inhibitors into pure water, heating and uniformlystirring, and performing spray drying, calcinations and reduction carbonation processes, so as to obtain a target product the nanometer WC powder. The nanometer WC powder is stable in performance, single in phase, uniform in components, narrow in grain fineness distribution, fine in crystal particles, and easy in powder component control, and has industrial and mass production capacity.

The invention discloses a method for preparing glyoxylate by catalytic oxidation of oxalic aldehyde; in the method, 20-100 mesh microballoon silochrom are added into aqueous solution which is composed of ammonium metavanadate, niobium ammonium oxalate and ammonium dichromate for being soaked, and activated under the protection of nitrogen, thus preparing a catalyst; the oxalic aldehyde water solution is used as raw material, oxygen is led in in the presence of the catalyst in the invention, and catalytic oxidation reaction is carried out by pressurizing, thus obtaining the target product of glyoxylate in the invention. The yield of the glyoxylate obtained by the method can be more than or equal to 57 percent in a single reaction and the purity is more than 99 percent. Compared with the prior art, the conversion rate of the oxalic aldehyde and the productive rate of the glyoxylate are improved, the product purity is high and the quality is stable, thus being suitable for industrial production.

The invention discloses a high-property modified nitrile butadiene rubber cable material used for ships. The cable material comprises the following raw materials in parts by weight: 20-40 parts of nitrile butadiene rubber, 5-10 parts of modified polyurethane composite material, 12-18 parts of styrene butadiene rubber, 5-15 parts of butadiene rubber, 1-2 parts of oleic acid, 0.5-1.5 parts of stearic acid, 1-2 parts of ammonium dichromate, 0.8-1.4 parts of dibenzothiazyl disulfide, 15-30 parts of kaolin, 8-12 parts of pottery clay powder, 42-55 parts of white carbon black, 5-10 parts of graphite, 1-3 parts of octyl-phenolic tackifying resin, 10-30 parts of ceramic fibers, 20-40 parts of modified active fibers, 0.5-1.5 parts of diisooctyl phthalate, 1-1.4 parts of aromatic hydrocarbon oil, 0.4-0.8 part of naphthenic hydrocarbon oil, 0.5-1.4 parts of antioxidant AT-215, 1-3 parts of ultraviolet absorber UV-531 and 1-2 parts of ultraviolet absorber TB75. The cable material has good thermal oxidative stability and excellent mechanical properties and is resistant to aging.

The invention discloses a preparation method of a nano Cr3C2 crystal whisker. The preparation method comprises the following steps: (1), by taking ammonium dichromate, a carbonaceous reducing agent and a halogenating agent as materials, placing the materials into distilled water, and uniformly stirring to prepare precursor liquor; (2), drying the precursor liquor to obtain a fluffy precursor mixture; (3), placing the precursor mixture into a reaction furnace, preserving heat for 0.5 hour-2 hours to carry out carbothermic reaction at a temperature of 700 DEG C-900 DEG C under an Ar gas or vacuum condition to obtain unpurified nano Cr3C2 crystal whisker; and (4), firing the unpurified nano Cr3C2 crystal whisker for 2 hours-8 hours at the temperature of 500 DEG C-600 DEG C in air for decarburization, removing Cr2O3 in HF liquor, and cleaning and drying to obtain the nano Cr3C2 crystal whisker with diameter smaller than 100 nm. The preparation method disclosed by the invention is simple in process, easily controllable in parameter and low in cost; the surface of the prepared Cr3C2 crystal whisker is smooth, and the crystal whisker diameter is smaller than 100 nm.

The invention discloses an aluminum conductor power cable material with an excellent mechanical property. The aluminum conductor power cable material is prepared from raw materials in parts by weight as follows: 30-40 parts of low-phenyl silicone rubber, 15-25 parts of nitrile rubber, 20-35 parts of metallocene polyethylene, 1.5-2.5 parts of tetramethyl thiuram disulfide, 1-2 parts of antimony dioxide, 0.5-0.6 parts of potassium ammonium dichromate, 0.3-0.8 parts of poly-p-nitrosobenzene, 1-2 parts of coumarone resin, 1.2-1.8 parts of coal pitch, 0.6-1.2 parts of chlorinated paraffin, 1-2 parts of tall oil, 1-2 parts of bis-dodecanol ester, 1-3 parts of pine tar oil, 10-20 parts of modified wheat protein, 5-15 parts of attapulgite, 50-75 parts of fumed silica, 8-16 parts of calcined clay, 0.5-1.5 parts of an ultraviolet absorber UV-531, 0.5-1.5 parts of an antioxidant 264 and 1-2 parts of zinc stearate. The aluminum conductor power cable material has good thermal stability and excellent extension resistance.

The invention provides a Method for preparation of nanochromium carbide powder, belonging to nanometal carbide powder preparation technical realm. Using ammonium dichromate, hydrazine hydrate, nanocarbon black and formaldehyde-phenol resin as raw material, first deoxidizing ammonium dichromate in aqueous solution by hydrazine hydrate and getting the amorphous nanoCr2O3, and then mixing nanoCr2O3, nanocarbon black and formaldehyde-phenol resin, getting nanoCr2O3 after 800-1100 Deg C heat treatment in vacuum furnace. The advantages of this invention are lies in: realizing the granularity of chromium carbide powder can controlled, the technics and equipment is simple and is the same with industrialization production.

The invention discloses a steel surface antirust agent combination product and application thereof. The steel surface antirust agent combination product comprises a coating agent, a detergent, a soaking agent and a passivator which are used independently, wherein the coating agent is a mixed solution of potassium hydroxide, ammonium sulfide and triethanolamine; the detergent is a mixed solution of nitric acid and thiourea; the soaking agent comprises an ammonium chloride solution and a zinc chloride solution; and the passivator is a mixed solution of ammonium dichromate and chromic acid. After the surface of steel is treated by the steel surface antirust agent combination product, the steel can be high in surface uniformity and low in surface roughness. More importantly, the antirust property of the surface of the steel is greatly improved, and good appearance of the outer surface of the steel can be maintained for a long time.

The invention discloses an abrasion resistance and impact resistance rubber sealing piece. The abrasion resistance and impact resistance rubber sealing piece comprises the following raw materials, by weight, of 20-50 parts of ethylene-propylene-diene monomer rubber, 10-20 parts of carboxyl-terminated butyronitrile rubber, 12-35 parts of chloroprene rubber, 1-2 parts of 1,1-double-(tertiary butyl peroxide) cyclohexane, 0.1-0.6 parts of dichromic acid sodium ammonium, 1-2 parts of titanate coupling agent TMC-TTS, 15-25 parts of nylon fibers, 2-6 parts of quartz powder, 10-20 parts of silicon carbide fibers, 2-8 parts of zirconia fibers, 1-2 parts of pine tar oil, 0.2-0.8 part of dioctyl phthalate, 1-2 parts of triethyl phosphate, 0.4-0.8 part of beeswax, 1-2 parts of vaseline and 1-3 parts of anti-aging agents. The abrasion resistance and impact resistance rubber sealing piece is good in toughness, excellent in impact resistance and abrasion resistance performance, good in corrosion resistance and aging-resistant performance, easily available in raw material and low in production cost.

The invention discloses a tearing-resistant and impact-resistant power cable, comprising a conductor and a jacket layer coated at the outer side of the conductor, wherein the jacket layer comprises the following raw materials in parts by weight: 20-40 parts of low-phenyl silicone rubber, 45-85 parts of acrylonitrile-butadiene rubber, 10-20 parts of chlorosulfonated polyethylene, 0.3-0.7 part of antimony dioxide, 1.5-2.5 parts of 2,4-dichlorobenzoyl peroxide, 1.5-2.5 parts of poly-p-nitrosobenzene, 0.3-0.5 part of potassium ammonium dichromate, 1.5-2.5 parts of phenolic resin, 2-4 parts of C5 petroleum resin, 10-16 parts of superfine talc powder, 10-18 parts of lignin, 45-65 parts of sepiolite powder, 4-10 parts of halloysite, 10-20 parts of modified betaine, 2-4 parts of an antioxidant 1076, 0.4-0.8 part of dilauryl thiodipropionate, 2-4 parts of epoxidized soybean oil, and 0.5-1 part of zinc stearate.

The invention discloses a rat-bite-preventing cable sheath material. The rat-bite-preventing cable sheath material is prepared from raw materials in parts by weight as follows: 60-80 parts of nitrile silicone rubber, 15-25 parts of butyl rubber, 30-40 parts of chlorosulfonated polyethylene, 1.5-2.5 parts of 1,1-di-(tert-butylperoxy)cyclohexane, 2-3 parts of sodium ammonium dichromate, 115-125 parts of a filling reinforcing agent, 3-6 parts of epoxidized soybean oil, 2-4 parts of dioctyl phthalate, 4-6 parts of stearic acid and 2.5-4 parts of an anti-aging agent, wherein the filling reinforcing agent is prepared from components in parts by weight as follows: 15-20 parts of a starch complex, 30-40 parts of hard pottery clay, 20-30 parts of silk fibers, 8-16 parts of diatomite and 25-35 parts of fumed silica. The rat-bite-preventing cable sheath material has excellent rat-proof performance, prevents a cable from being bitten and damaged by rats, and is quite good in tensile strength and wear resistance and low in cost.

The invention discloses a preparation method for nano chromium carbide powder, and belongs to the technical field of preparation of inorganic materials. The preparation method comprises the following steps: adding saccharose or glucose into ammonium dichromate serving as a raw material under an acidic condition, reducing ammonium dichromate to generate chromic hydroxide nano particles, then performing spray drying for dewatering, putting dewatered raw materials into a reaction furnace, carrying out thermal treatment under hydrogen protection atmosphere or vacuum, decomposing the chromic hydroxide nano particles into chromic oxide nano particles, and carbonizing the newly generated active chromic oxide particles into a chromium carbide nano material by the saccharose or glucose. The prepared nano chromium carbide is high in purity, high in dispersivity, large in specific surface area and uniform in particle size distribution. By simple adjustment on the acidicity or the carbonization temperature of the experiment, nano chromium carbide powder of different particle sizes from 20 to 100 can be obtained. The method has the characteristics of readily available raw materials, low cost, no use of an organic solvent, simple production technology, suitability for large-scale production and the like.

The invention discloses a preparation method of nano-Cr3C2 powder and application of the nano-Cr3C2 powder to a multi-element alloy coating and belongs to the technical field of alloy materials. The preparation method of the nano-Cr3C2 powder, disclosed by the invention, comprises the following four steps: 1, mixing: putting ammonium dichromate powder and nano-carbon black powder into distilled water or de-ionized water; mixing and uniformly stirring until fluid is formed; adding the fluid into a mold and pressing and molding to form a precursor; 2, quickly freezing: rapidly transferring the precursor into a quick-freezing space for quickly freezing; 3, carrying out freeze-drying: rapidly transferring the quickly-frozen precursor into a vacuum freezing and drying cabin and carrying out the freeze-drying; 4, carbonizing: closing a cold trap of the vacuum freezing and drying cabin and gradually reducing high-valence oxide of chromium to low-valence oxide of chromium through carbon along with the rising of temperature, so as to prepare the multi-element alloy coating. The prepared multi-element alloy coating has the characteristics that the aims of heat-resisting and wear-resisting properties and high bonding strength are realized.

The invention discloses an extracting method for lactone in gingkoes. The invention is mainly prepared from, by weight, 70-78 parts of portland cement, 30-38 parts of AEC expansive cement, 20-30 parts of white cement, 30-35 parts of methyl hexenoic acid methyl ester, 10-18 parts of vinyl acetate resin emulsion, 12-14 parts of potassium hydroxide, 4-8 parts of starch, 3-6 parts of ammonium dichromate, 10-18 parts of light calcium carbonate, 10-15 parts of polypropylene short fiber, 8-10 parts of carboxymethylcellulose, 10-16 parts of fly ash glass beads, 5-9 parts of kaolin, 5-9 parts of vermiculite and 5-7 parts of ammonium polyphosphate. The invention is long in fireproof time limit, good in adhesion property, convenient to construct and suitable for various tunnel walls and simultaneously has the sound absorption function on the basis of fire protection.

The invention discloses an environmental protection safe firework medicine. The environmental protection safe firework medicine is composed of an A chemical component, a B chemical component, and a Cchemical component; the A chemical component is composed of, by weight, 55 to 70 parts of ammonium dichromate, 10 to 20 parts of potassium hydrogen terephthalate, 2 to 8 parts of Potassium Permanganate, and 5 to 15 parts of diatomite; the B chemical component is composed of, by weight, 50 to 55 parts of ammonium dichromate, 3 to 10 parts of copper oxide, 5 to 8 parts of barium nitrate, 20 to 25 parts of bamboo charcoal fiber cotton, and 20 parts of diatomite; and the C chemical component is composed of 44 to 60 parts of ammonium dichromate, 8 parts of metal powder, 5 parts of basic cupric carbonate, 2 to 10 parts of Phenolic Resin, 1 to 5 parts of Polyisobutylene, 5 to 10 parts of Guanidine nitrate, and 5 parts of diatomite. The environmental protection safe firework medicine possesses following advantages such as low smoke and residue in firework discharge, and better environment protection performance and higher safety.

The invention discloses a high nitrogen type volatile solvent colloid gunpowder. The high nitrogen type volatile solvent colloid gunpowder comprises, by weight, 30 to 60 parts of ammonium perchlorate,10 to 20 parts of nitroguanidine, 30 to 60 parts of ammonium dichromate, 50 to 80 parts of nitrostarch, 40 to 70 parts of NC, 1 to 1.5 parts of diphenylamine, 1 to 1.5 parts of camphor oil, and 1 to1.5 parts of water. The high nitrogen type volatile solvent colloid gunpowder is excellent in safety performance, high in stability, is low in smoke performance, is friendly to the environment, is suitable to be added into various firework firecracker products, and is low in cost.

The invention discloses minimum-smoke gunpowder. The minimum-smoke gunpowder is characterized by being prepared from NC, a solvent, ammonium dichromate, a reducing agent, graphite and vaseline; the content of each component is as follows in parts by weight: 90 to 105 parts of the NC, 2 to 5 parts of the solvent, 1 to 2 parts of the ammonium dichromate, 2 to 5 parts of the reducing agent, 2 to 3 parts of the graphite and 1 to 3 parts of the vaseline. The minimum-smoke gunpowder has the advantages that the purchasing price of each component is low, only less minimum smoke is generated in a combustion process, and requirements of safety standards of existing firework production and environment-friendly explosion and the like can be met.

The invention discloses a mechanical equipment rusting treatment agent and a treatment method thereof. The treatment agent is prepared from, by mass part, 30-40 parts of glycerinum, 10-20 parts of inorganic acid, 5-10 parts of sodium citrate, 5-10 parts of ammonium dichromate, 2-5 parts of quartz powder, 2-5 parts of sodium hydroxide solution, 2-5 parts of silicone acrylic emulsion, 1-3 parts of nitrite, 2-5 parts of improver, 2-3 parts of penetrant, 1-3 parts of water-soluble surface active agent, 1-3 parts of thickening agent and the balance water. The mechanical equipment rusting treatmentagent and the treatment method thereof have the beneficial effects that a preparation method is simple, construction is convenient, a rusted surface can be fast removed, and high practicality is achieved; and energy consumption is reduced, production efficiency is improved, and the service life of engineering machines is prolonged.

The invention provides an ammonium dichromate and sodium sulfate mixed crystal as well as a preparation method and application thereof. The preparation method comprises the following steps: heating amixed solution of sodium dichromate, ammonium sulfate and sodium sulfate, and conducting cooling and crystallizing to obtain a saturated salt solution; and heating the obtained saturated salt solution, then adding ammonium sulfate, then adding sodium dichromate, conducting stirring for reaction, and then conducting cooling for crystallization to obtain mixed crystals and crystallization mother liquor. According to the invention, the saturated salt solution is used as a reaction base solution, and then the mixed crystal with uniform, dispersed and non-sticky particle size is prepared by controlling the reactant adding mode and proportion, reaction and post-treatment process, so that the generation of double salt is avoided, and the composition of the mixed crystal is ensured to meet the requirements; meanwhile, due to the use of the reaction base solution, evaporation and concentration steps can be omitted, and the crystallization yield is increased; and a chromium oxide green pigment is prepared from the obtained mixed crystal, so that the problem of difficult feeding in industrial production can be effectively solved, and the obtained product has better chromaticity parameters andexcellent performance.