43results about How to "Increase the degree of oxidation" patented technology

The wet combined fume desulfurizing and denitrifying process with chloric strong oxidant enhanced urea has the fume to be treated contacted sufficiently with the mixed absorbent liquid containing urea and chloric strong oxidant inside the absorbing reactor so as to eliminate NOx and SO2 through absorption before being exhausted. The chloric strong oxidant is sodium chlorite, sodium hypochlorite, bleaching powder or their mixture. The process has high denitrifying efficiency, high fume purifying effect, simple structure, easy operation and small occupied land. The said process can reach NOx eliminating rate of 75-98 % and desulfurizing efficiency over 95 %.

The invention discloses a coal-fired flue gas denitration and desulfurization method combined with the urea wet method. The method comprises the following steps: spraying 50wt% of hydrogen peroxide at the coal-fired flue gas inlet of a absorption tower while keeping the molar ratio of H2O2 to NO to be 2-3, so as to oxidize NO in the coal-fired flue gas to NO2 and increase the oxidization degree of NOX; and perform denitration and desulfurization simultaneously by using the urea aqueous solution in the absorption tower. The method of the invention increases the denitration rate of the coal-fired flue gas denitration and desulfurization combination technology by increasing the oxidization degree of NOX and the temperature of the absorption solution. The method has simple technology, convenient operation and management, no secondary pollution and good environmental and economic benefits.

The invention relates to the technical field of graphene nano-sheets, and discloses a method for preparing a graphene nano-sheet based on crystalline flake graphite. According to the preparation method, crystalline flake graphite serving as a raw material is oxidized by adopting low temperature, medium temperature and high temperature three stages, so that the side reaction in the graphite oxidizing process can be effectively controlled, and the graphite oxidizability can be improved; the graphite oxide is pre-stripped at a low temperature, which has lower cost in comparison with that for high-temperature stripping at about 1000 DEG C, and is applicable to industrial application. The ball mill method assisted with discharge plasma is adopted, the preparation method is simple in process andcan be produced in a large scale, has relatively small damage to graphite lamella, few-layer graphene nano-sheet with relatively good crystallinity can be easily obtained, and a good reduction effectcan be achieved for graphite by adding a solid-state ball mill medium, and the prepared graphene nano-sheet has high quality and a multi-fold translucent yarn structure.

The invention relates to the field of the flue gas purification treatment technology and in particular relates to a normal-temperature gas-phase catalytic oxidation-absorption reduction two-stage type flue gas denitrification process. The process can improve the oxidization degree of nitric oxide and can effectively remove nitrogen oxides under low power consumption. The normal-temperature gas-phase catalytic oxidation-absorption reduction two-stage type flue gas denitrification process comprises the following steps: (1) flue gas enters an oxidation tower after being desulfurized and dedusted; (2) NO in flue gas is subjected to plasma facilitated or enhanced gas phase catalytic oxidation at normal temperature to generate high-valence nitrogen oxide; (3) high-valence nitrogen oxide enters an absorption reduction tower along with flue gas, and reducing agent solution is sprayed into the absorption reduction tower to absorb and reduce the high-valence nitrogen oxide to generate nitrogen gas, carbon dioxide, water or sulphate; and (4) flue gas after nitrogen oxide removal is discharged.

The invention provides a method for reducing nitrogen oxides in flue gas of a medium and small sized industrial coal burning boiler through a wet-method sulfur removing technology. The method comprises the following steps: conducting dust removing and primary sulfur removing on flue gas generated by the coal burning boiler; collecting alkali liquor comprising sulfur removing product sodium sulfite of primary desulfuration according to a dual-alkali method; conducting oxidation treatment on the pretreated flue gas to integrally oxidize NO and residuary sulfur dioxide in the pretreated flue gas; utilizing the oxidized flue gas to get in contact with an alkali liquor, thereby removing nitrogen dioxide and sulfur oxide generated after oxidation in the oxidized flue gas to obtain purified flue gas; conducting gas-water separation to discharge flue gas which meets the environmental standard. Compared with the conventional dry-process flue gas denitration technology, the method provided by the invention has the advantages that desulfurization and denitrification can be simultaneously realized only by additionally arranging an oxidation reactor section in a conventional dual-alkali method absorbing system, so that the economic performance is very high.

The invention belongs to the technical field of inorganic material preparation, and particularly relates to a preparation method of high-intrinsic-degree grapheme. The preparation method comprises thefollowing steps that a graphite material is prepared into a positive electrode; sulfate is prepared into an electrolyte, firstly the electrode is pretreated under the condition of an applied voltage,then the pH of a solution is adjusted to be alkaline by adding ammonia water, and electrolytic stripping of the graphite positive electrode is performed at a certain temperature; and an electrolyzedproduct is subjected to solid-liquid separation and drying to obtain the high-intrinsic-degree grapheme. Lower oxidation activity of a solvent to the graphite material can be ensured by controlling the pH value of the electrolyte, the reduction of the oxidation degree of the product grapheme is facilitated, and the improvement of the quality of the grapheme is further facilitated. The grapheme isprepared form conventional chemical raw materials, the raw materials are low in cost and easy to obtain, and industrialization is convenient.

The invention belongs to the technical field of artificial boards, and particularly relates to a preparation method of a high-strength formaldehyde-free wood fiber board, the fiber board and application. The preparation method comprises the following steps of S1, wood pretreatment, wherein after poplar waste is crushed, two-step dipping with a mixed solution of potassium hydroxide and sodium sulfite and a calcium chloride solution, high-temperature treatment and drying for later use are carried out; S2, pre-pressing and forming; and S3, hot pressing for board forming. The mixed solution of potassium hydroxide and sodium sulfite is used for treating cellulose in wood waste residues, decomposition and hydrolysis of hemicellulose, lignin and the like are accelerated, TEMPO is used for oxidizing the cellulose, the oxidation degree is improved, calcium ions and cellulose nanofibers are crosslinked, the self viscosity is improved, and hot pressing forming of the fiber board is facilitated.

The invention provides a device for treating NOX tail gas in a nitric acid metal dissolving process. A gas-liquid mixing module is used for mixing gas and liquid in a kettle body, and a liquid phase forms negative pressure relative to other spaces in the kettle body through a mixing effect; an oxygenation control sensor collects an oxygen redundancy detection signal in the kettle body and sends the oxygen redundancy detection signal to an automatic control system; a pressure sensor and a temperature sensor respectively collect a pressure signal and a temperature signal of the kettle body and send the signals to the automatic control system; the automatic control system respectively controls a nitric acid control metering module, an oxygenation control module, a safety pressure relief module and a temperature control module to adjust the nitric acid adding speed, the oxygenation speed and the temperature in the kettle body according to the oxygen redundancy detection signal, the pressure signal and the temperature signal. The invention further provides a treatment method and a control terminal. The preparation process of nitrate and the absorption and the reuse of NOx gas are uniformly treated, and production, conversion, absorption and reuse of NOx are realized in one step in the reaction kettle.

The invention discloses an integral purification device for ship tail gas. The integral purification device for the ship tail gas comprises a motor and a purification device shell, wherein the purification device shell comprises a sprinkling device, a rotary silk screen liquid atomization and dispersion device and a rotary demister. In the device, the sprinkling device can be applied to a pipelineto sprinkle liquid phase oxidizing agent, the degree of oxidation of nitric oxide is improved in the pipeline, and land occupation is reduced so as to bring convenience in being subsequently adsorbedby absorbent in the rotary silk screen liquid atomization and dispersion device; in the rotary silk screen liquid atomization and dispersion device, gas flows along an axial direction, centrifugal resistance does not need to be overcome, and gaseous phase resistance is reduced; liquid is sprayed out from a liquid distributor to collide with a rotary silk screen, then, the liquid is cut into smalldrops by the multilayer silk screen to be evenly distributed in a fog shape, the cross flow contact area of the gaseous phase and the liquid phase is increased, and the mass transfer of the gaseous phase and the liquid phase is reinforced. The rotary demister utilizes the silk screen which rotates at a high speed to keep the surface of the demisting silk screen to be updated, gas-liquid separation is realized, and entrainment and the waste of absorbent are avoided.

The present invention proposes a method and system for reducing vanadium-titanium ore with coal pyrolysis gas. The method includes the steps of: coal pyrolysis: adding raw coal from the coal pyrolysis furnace silo to the coal pyrolysis furnace, at a temperature of 700-900°C , pyrolysis to generate solid semi-coke and pyrolysis gas; pyrolysis gas heating: the pyrolysis gas enters the heating furnace through the pipeline to be heated to obtain a high-temperature reducing gas of 1000‑1100 °C; vanadium-titanium ore reduction: the high-temperature reducing gas is transported After entering the shaft furnace, react with semi-coke, and reduce vanadium-titanium ore to obtain reduced vanadium-titanium metallized pellets; wherein, the pressure of reducing gas entering the shaft furnace is 0.45MPa-0.9MPa, and the temperature is 950-1050 ℃. The invention organically combines coal chemical industry with metallurgical production, effectively utilizes H2O and CO2 in coal pyrolysis gas to oxidize semi-coke, so as to increase the content of reducing gas and reduce the production cost and energy consumption of vanadium-titanium direct reduction iron.

The invention relates to a method for preparing cobalt clad beta-NiOOH by a liquid phase oxidation method. In the technical scheme of the invention, the method for preparing the cobalt clad beta-NiOOH by the liquid phase oxidation method comprises the following steps of: preparing a NaOH aqueous solution, adding cobalt clad Ni(OH)2 and evenly stirring; adding an oxidizing agent at the temperature of 15-45 DEG C, stirring for 1-3h at the temperature of 40-85 DEG C, and standing for 0.5-1h; removing supernatant liquid; precipitating and washing; and drying. The molar ratio of the NaOH to the cobalt clad Ni(OH)2 to the oxidizing agent is 1: (0.7-1.0): (0.35-0.6). The method is simple to operate and improves the oxidizability of the Ni(OH)2, and the percent conversion of the cobalt clad beta-NiOOH is at least 95 percent; the cobalt clad beta-NiOOH prepared by the method is used as a secondary battery nickel electrode additive, and a manufactured secondary battery discharge plateau is high and has long cycle life.

The invention relates to the field of inorganic nonmetallic materials, and in particular relates to a preparation method of microcrystalline graphite oxide. In the presence of a nitrate additive, microcrystalline graphite oxide with a high oxidation degree is obtained by virtue of staged reaction between a strong oxidant and microcrystalline graphite in a sulfuric acid solution. The preparation method provided by the invention has the following advantages: a technology of temperature programming and staged reaction is adopted, so that the happening of side reaction during the preparation of microcrystalline graphite oxide by oxidizing microcrystalline graphite can be effectively controlled, and then the purity and oxidation degree of a microcrystalline graphite oxide product are improved; and by virtue of the application of the additive, the time for intercalation of microcrystalline graphite can be effectively shortened, and then the reaction time of the whole process flow is shortened. Therefore, the preparation method provided by the invention has the characteristics of short reaction time and simple process, and is beneficial for realizing scale production and application of microcrystalline graphite; and the preparation of microcrystalline graphite oxide has not been reported at present.

The invention relates to an iron oxide red pigment two-step oxidation process waste gas treatment method, which comprises: 1, removing steam and iron red particles from waste gas by using a heat exchange cooling method to generate first-stage waste gas; 2, oxidizing NO in the first-stage waste gas into NO2 by using N2O4 removed concentrated nitric acid to generate second-stage waste gas; 3, removing NO2 and NO from the second-stage waste gas by using N2O4 removed dilute nitric acid to generate third-stage waste gas; 4, further removing NO2 and NO from the third-stage waste gas by using a sodium hydroxide solution to generate fourth-stage waste gas; and 5, reducing NO2 in the fourth-stage waste gas into N2 by using a urea solution so as to generate fifth-stage waste gas, wherein the fifth-stage waste gas achieves the discharge standard. According to the present invention, with the iron oxide red pigment two-step oxidation process waste gas treatment method, the oxidation degree of the waste gas treatment can be increased, the absorption efficiency of the waste gas treatment can be increased, and the final waste gas can meet the discharge standard.

The invention discloses a method for preparing oxidized chitosan and derivatives thereof by an electrolytic method. According to the method, a small amount of sodium iodate is adopted in an electrolytic tank to selectively oxidize chitosan and derivatives thereof under a dark condition, and after dialysis separation, oxidized chitosan containing aldehyde groups with high chemical reaction activityand derivatives thereof are obtained. Compared with a traditional method, the method has the advantages of being small in oxidant dosage, controllable in oxidation degree, green and environmentally friendly, and is a novel environmentally-friendly preparation method of oxidized chitosan and derivatives thereof.