9results about "Arsenic oxides/hydroxides/oxyacids" patented technology

The invention discloses a closed cycle utilization method of a zirconium-based arsenic removal agent. The method comprises the following steps: (1) taking zirconium sulfate as the arsenic removal agent used for the first time; the roasted material prepared in the step (4) is adopted as an arsenic removal agent for follow-up recycling; adding an arsenic removal agent into the arsenic-containing acid liquid and / or zirconium arsenate thin slurry, and carrying out solid-liquid separation to obtain arsenic-removed slag and arsenic-removed liquid; (2) mixing the arsenic-removed liquid with macroporous composite exchange resin, and carrying out zirconium removal reaction to obtain zirconium-loaded resin and purified liquid; (3) mixing the zirconium-loaded resin with the arsenic-containing acid solution, and separating resin particles from the slurry containing the zirconium arsenate precipitate by using a solid-liquid separation device to obtain regenerated resin and zirconium arsenate thin slurry; (4) mixing the arsenic-removed slag with a sulfuric acid solution and elemental sulfur, carrying out a reduction roasting reaction to obtain a roasted material, and condensing gas released by the reaction to obtain a mixture of sulfuric acid and arsenious acid; and (5) cooling the mixture of sulfuric acid and arsenious acid, and carrying out centrifugal separation to obtain arsenic trioxide solid and a sulfuric acid solution.

Method for producing a surface-treated gallium arsenide substrate, comprising the following steps: a) Providing a gallium arsenide substrate; b) Oxidation treatment of at least one surface of the gallium arsenide substrate in the dry state using UV radiation and / or ozone gas; c) Contacting at least one surface of the gallium arsenide substrate with at least one liquid medium; comprising the following sub-steps: ci) Contacting at least one surface of the gallium arsenide substrate with alkaline aqueous solution, c-ii) subsequent contact of at least one surface of the gallium arsenide substrate with water, c-iii) subsequent contact of at least one surface of the gallium arsenide substrate with acidic aqueous solution, c-iv) subsequent further contact of at least one surface of the gallium arsenide substrate with water. d) Marangoni drying of the gallium arsenide substrate.

The application belongs to the technical field of metallurgy, and discloses a purification method of diarsenic trioxide. The purification method comprises the following steps: S1. heating and reacting the crude diarsenic trioxide mixed with nitrate at 250-350 DEG C for 2-4 h; S2. raising the reaction system obtained in step S1 to 550-650 DEG C and maintaining for 3-6 h to sublimate the diarsenic trioxide, so as to obtain roasting slag and arsenic-rich flue gas; and S3. recovering diarsenic trioxide from the arsenic-rich flue gas obtained in step S2. The application uses nitrate as an antimony removal agent, and solves the problem that arsenic and antimony are difficult to separate due to similar physical and chemical properties. The application utilizes the strong oxidizing property of nitrate, and realizes efficient recovery of diarsenic trioxide at a low temperature. The obtained diarsenic trioxide has high purity, and the recovery rates of arsenic and antimony are high.

The invention relates to a regeneration method of a waste denitration catalyst, which comprises the following steps: mixing the waste denitration catalyst with a first treatment solution for reaction to dissolve out arsenic element in the waste denitration catalyst to obtain an arsenic-containing treatment solution and an arsenic-removed catalyst; the arsenic-containing treatment liquid reacts with a first alkaline substance, so that the arsenic element and the iron element in the arsenic-containing treatment liquid are converted into precipitates; reacting the precipitate with a second alkaline substance to dissolve the precipitate containing the arsenic element so as to obtain a solution containing ammonium meta arsenite; and heating and decomposing the solution containing the ammonium meta arsenite to obtain arsenic trioxide. According to the regeneration method of the waste denitration catalyst in one embodiment, efficient leaching of harmful component arsenic oxide and low leaching of active components can be achieved, selective dissolution of arsenic is achieved, and therefore efficient regeneration of the arsenic-containing waste denitration catalyst is achieved.

The invention discloses a resource recycling method for arsenic in wastewater, and belongs to the technical field of wastewater treatment and resource recycling. The resource recycling method for arsenic in wastewater comprises the following steps: preparing a mixed solution of sodium iodide, sodium sulfite and sodium carbonate, and adding the mixed solution into arsenic-containing wastewater to be treated; the method comprises the following steps: introducing nitrogen into arsenic-containing wastewater to be treated containing sodium iodide, sodium sulfite and sodium carbonate, stirring and carrying out light treatment, reacting to obtain an arsenic-containing solid, and sequentially centrifuging and freeze-drying to recycle the arsenic-containing solid. According to the method, arsenate in the wastewater can be reduced and separated to generate high-purity arsenic elementary substance and arsenic trioxide products. Compared with the prior art, the method has the advantages that generation and accumulation of arsenic-containing solid wastes are avoided, the risk of secondary pollution is eliminated, and efficient recovery and resource utilization of the arsenic element are realized.

The invention discloses a method for regenerating and recycling a titanium-based arsenic removal agent, which comprises the following steps: (1) mixing a titanium-rich material with a sulfuric acid solution, and carrying out roasting reaction to obtain a roasted material A as the titanium-based arsenic removal agent used for the first time; the method comprises the following steps: adding a titanium-based arsenic removal agent into an arsenic-containing acid solution, and carrying out solid-liquid separation to obtain arsenic-removed slag and arsenic-removed solution; (2) mixing the arsenic-removed slag with a sulfuric acid solution and sulfur, carrying out a reduction roasting reaction to obtain a roasted material B, and condensing gas released by the reaction to obtain a mixture of sulfuric acid and arsenious acid; (3) cooling the mixture of sulfuric acid and arsenious acid to below 10 DEG C, and performing centrifugal separation to obtain arsenic trioxide solid and a sulfuric acid solution; (4) mixing the arsenic-removed liquid with macroporous composite exchange resin, and carrying out titanium removal reaction to obtain titanium-loaded resin and purified liquid; and (5) mixing the titanium-loaded resin with the arsenic-containing acid solution, and separating resin particles from the slurry containing the titanium arsenate precipitate by using a solid-liquid separation device to obtain regenerated resin and titanium arsenate thin slurry.

The invention discloses an arsenic-containing flue gas purification and arsenic resource high-value recovery process which comprises the following steps: step 1, flue gas pretreatment: removing large-particle smoke dust through a dust remover; 2, waste heat recovery, wherein the high-temperature flue gas is introduced into a waste heat boiler to recover flue gas waste heat; 3, spray cooling: introducing the flue gas into a spray tower, reversely atomizing, spraying water, absorbing heat, and condensing to form crystals; step 4, crystal stripping: scraping, stripping and collecting the crystals through a mechanical scraper device to obtain coarse arsenic trioxide crystals; step 5, settling and slow cooling: pouring the residual gaseous arsenic trioxide into a cooling settling tank by a negative pressure fan for slow cooling settling; step 6, dissolving and recrystallizing: adding deionized water into the crystal, heating for dissolving, filtering the solution after impurity precipitation, carrying out solid-liquid separation, cooling and recrystallizing to obtain a high-purity arsenic trioxide crystal; according to the arsenic trapping device, efficient trapping of arsenic is achieved through crystallization on the wall of the spray tower and slow cooling of the settling tank, crystals are stripped in real time through the mechanical scraper, and the stubborn disease that equipment is scaled and blocked is radically treated.

The invention belongs to the field of environmental protection, and discloses a method for recovering arsenic trioxide from arsenite-containing wastewater. According to the method, arsenite in the wastewater can be converted into arsenic trioxide, resource recycling of arsenic is achieved, waste is turned into wealth, and the problem of accumulation of a large amount of arsenic-containing solid waste generated by a traditional water treatment technology and the risk of secondary pollution are avoided. The method has the advantages of being short in technological process, high in arsenic recovery rate and the like, and has profound significance for improving the economic benefits of enterprises and walking a green and sustainable development road.

The invention discloses a method for efficiently recovering As2O3 in copper smelting arsenic-rich ash, and relates to the field of copper smelting arsenic-rich ash, the method comprises the following steps: pretreatment: crushing the copper smelting arsenic-rich ash, screening until the particle size is less than or equal to 150 microns, and removing mechanical impurities; low-temperature sulfuric acid curing: mixing the pretreated arsenic-rich ash with a sulfuric acid solution in proportion, carrying out low-temperature curing reaction under a stirring condition, controlling the curing temperature to be 50-90 DEG C and the reaction time to be 2-6 hours, and generating cured flue gas containing As2O3; collecting flue gas; carrying out gradient condensation collection and tail gas treatment; according to the method for efficiently recycling As2O3 in the arsenic-rich ash in copper smelting, the arsenic removal rate is high, specifically, through low-temperature sulfuric acid curing phase regulation and control, the arsenic removal rate is larger than or equal to 98% and is obviously superior to 85%-92% of the prior art; the produced As2O3 product is high in purity, low in energy consumption, small in environmental pollution, high in phase conversion efficiency, high in process stability, wide in raw material adaptability and remarkable in economic benefit.