20 results about "Arsenous acid" patented technology

The invention discloses a magnetic iron mineral and phosphate tailing material and application thereof in treatment of arsenic and cadmium pollution. A low-cost phosphate tailing material is taken as an object, and an environmental functional material loaded with magnetic gamma-Fe2O3 and other iron minerals is prepared by adopting a method of'rapid thermal activation-primary addition of a modifying agent-mineral phase conversion '. The magnetic iron mineral and phosphate tailing material can efficiently adsorb cadmium ions, arsenate ions and arsenite ions, has a synchronous adsorption effect on coexisting cadmium ions and inorganic arsenic, and can be used as an efficient passivation repair material for arsenic-cadmium combined polluted soil. The material also has magnetism, is easy to separate and recover, and also can be combined with a magnetic separation technology to serve as a material for synchronously removing arsenic and cadmium pollutants in a water body or soil.

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.

The invention relates to a preparation method of a carbon-based blocky As (III) oxidation-adsorption material, and belongs to the technical field of inorganic arsenic adsorption. The invention relates to a preparation method of a carbon-based blocky As (III) oxidation-adsorption material, which comprises the following specific steps: immersing a bamboo stem into a stannous chloride and hydrochloric acid solution to obtain a sensitized biomass matrix; immersing the sensitized biomass matrix into a mixed solution of ammonia water and silver nitrate to obtain an activated biomass matrix; transferring the activated biomass matrix into a mixed solution of copper ions and a reducing agent to obtain copper-plated biomass; immersing the copper-plated biomass into a ferrous chloride solution, and performing freeze drying to obtain iron-doped copper hydroxide modified biomass; and transferring the dried iron-doped copper hydroxide modified biomass into a tubular furnace, and pyrolyzing under the protection of inert gas to obtain the high-performance carbon-based blocky As (III) oxidation-adsorption material. Arsenious acid ions can be efficiently oxidized and adsorbed.

Substantially cuboctahedral group III-V nanocrystals and nanocrystal compositions are disclosed. The nanocrystals may have crystalline cores comprising indium and / or gallium, and a pnictogen. The pnictogen is preferably phosphorus, arsenic, antimony, or a mixture thereof. A plurality of ligands may be coordinated to a surface of the crystalline core. These ligands may be organic compounds, inorganic compounds, or a mixture thereof. Example ligands include alkylamines, carboxylic acids, alkyl phosphonic acids, aromatic phosphonic acids, alkyl or aryl thiols, alkyl or aryl arsenous acids, and mixtures thereof. The nanocrystal quantum dots may be indium arsenide, InAs, indium antimonide, InSb, or InAs / Sb nanocrystals. An ink or a film comprising the group III-V nanocrystal compositions is also disclosed.

This invention provides a method for the co-reduction synthesis of zinc arsenide in an alkaline composite environment. The method innovatively uses a strongly alkaline solution as the basic electrolyte and simultaneously dissolves zinc oxide (ZnO) and arsenic trisulfide (As₂S₃) as the zinc and arsenic sources, respectively, to form Zn(OH)₄. 2‑ and AsS3 3‑ / AsO3 3‑ A multi-ion coexistence system was developed. By introducing multifunctional composite additives into this system, the electrodeposition process was synergistically regulated. Specifically, the reduction process of Zn(II) in situ modified the cathode interface, reducing the double-layer thickness and enhancing the adsorption and electron transfer of arsenite ions on the cathode surface. Simultaneously, the coupled co-deposition of arsenic and zinc effectively squeezed out the adsorption sites of water molecules on the cathode surface and the electron ratio of the hydrogen evolution reaction, thereby significantly suppressing the hydrogen evolution side reaction and the generation of highly toxic arsine (AsH3) gas. Ultimately, a uniform and well-bonded zinc arsenide deposition layer was obtained on the cathode surface.

The invention discloses a method for efficiently removing arsenic from a crude germanium tetrachloride solution based on arsenic hydride reduction, and belongs to the technical field of rare and noble metal metallurgy. According to the method, arsenic hydride gas is introduced into a crude germanium tetrachloride solution containing arsenic impurities under the protection of inert atmosphere and under the mild condition of 20-80 DEG C; the arsenic hydride and arsenic compounds such as arsenic trichloride, arsenious acid and arsenic acid in the solution are subjected to selective reduction reaction to generate simple substance arsenic solid precipitate. Then a germanium tetrachloride solution subjected to deep arsenic removal can be obtained through simple solid-liquid separation operation, obtained arsenic-containing solids are washed and dried, and resource recycling of crude arsenic products is synchronously achieved. The method provided by the invention initiates a new arsenic removal path of reduction-precipitation, has the outstanding advantages of high arsenic removal efficiency, good selectivity, short process flow, no secondary pollution and capability of realizing arsenic resource utilization, and provides a brand new solution for green and efficient preparation of high-purity germanium tetrachloride.

The invention provides an iron-modified silicon-calcium-based mineral material and application of the iron-modified silicon-calcium-based mineral material in passivating and repairing cadmium and arsenic pollution. According to the technical scheme disclosed by the invention, high-temperature slag of a yellow phosphorus production process is selected as a silicon-calcium-based mineral raw material, and the silicon-calcium-based mineral material loaded with spherical nanoscale iron minerals is prepared through the steps of ferric salt dipping, alkali liquor dropwise adding, natural settling, thermal reaction and cleaning. According to the mineral loading modification scheme, the adsorption capacity of the material to cadmium ions, arsenate ions and arsenite ions is remarkably improved at the same time, and the disclosed iron-modified silicon-calcium-based mineral material can adsorb cadmium and arsenic pollutants at the same time and can be used for removing the cadmium ions, the arsenate ions or (and) the arsenite ions in a water body; and the silicon-calcium-based waste can also be used as a passivation repair material for treating cadmium and arsenic pollution of a soil environment, and the application way of the silicon-calcium-based waste is expanded.

To provide an iron-oxidizing bacterium that enables efficient removal of arsenic (especially, arsenite and arsenate) from an arsenic-containing liquid, a material containing the iron-oxidizing bacterium, and a method for removing arsenic from an arsenic-containing liquid using the iron-oxidizing bacterium.SOLUTION: An iron-oxidizing bacterium is capable of oxidizing ferrous ions to ferric ions and oxidizing arsenite to arsenate. A material containing the iron-oxidizing bacterium further comprises a support material suitable for habitation of the iron-oxidizing bacterium. A method for removing arsenic from an arsenic-containing liquid using the iron-oxidizing bacterium includes: a bacterium addition step; a reaction step including formation of ferric hydroxide (iron(III) hydroxide) minerals capable of adsorbing arsenite and arsenate, and bacterium-mediated oxidation of arsenite to arsenate; and a separation step of separating ferric hydroxide minerals having adsorbed arsenite and / or arsenate from the arsenic-containing liquid.SELECTED DRAWING: Figure 1

The present application relates to a method for preparing a carbon-based bulk As(III) oxidation-adsorption material, and belongs to the field of inorganic arsenic adsorption technology. A method for preparing a carbon-based bulk As(III) oxidation-adsorption material, the specific steps of which are as follows: taking bamboo stems, immersing them in a stannous chloride and hydrochloric acid solution to obtain a sensitized biomass matrix; immersing the sensitized biomass matrix in a mixed solution of ammonia and silver nitrate to obtain an activated biomass matrix; transferring the activated biomass matrix to a mixed solution of copper ions and a reducing agent to obtain a copper-plated biomass; immersing the copper-plated biomass in a ferrous chloride solution and freeze-drying it to obtain an iron-doped copper hydroxide-modified biomass; transferring the dried iron-doped copper hydroxide-modified biomass to a tubular furnace, pyrolyzing it under inert gas protection to obtain a high-performance carbon-based bulk As(III) oxidation-adsorption material; and efficiently oxidizing and adsorbing arsenite ions.

The invention relates to multifunctional integrated hydrotalcite (MgAlEu-LDH) which has the capabilities of efficient adsorption, oxidation repair and real-time monitoring of heavy metal pollution. According to the material, the adsorption selectivity is enhanced by introducing rare earth element europium (Eu < 3 + >), a dual mechanism of'coordination adsorption-photocatalytic oxidation 'is realized by utilizing the photocatalytic characteristic of the material, and an ultra-stable mineralization structure is constructed. The preparation method comprises the following steps: weighing magnesium chloride, aluminum chloride and europium chloride according to a molar ratio of 2: 1: 0.1 to prepare a salt solution, reacting the salt solution with an alkali solution in a colloid mill, aging, washing and drying to obtain MgAlEu-LDH, and calcining at 350 DEG C to obtain MgAlEu-LDH. The fluorescence characteristic of Eu < 3 + > can be used for monitoring the adsorption process in situ in real time, and the fluorescence intensity of Eu < 3 + > is quenched along with the increase of arsenite adsorption time. Experiments show that the material is high in arsenic adsorption rate, the adsorption process conforms to a Langmuir model, the fluorescence intensity change is related to the adsorption process, and an economic and environment-friendly technical scheme is provided for heavy metal pollution remediation.

The invention belongs to the field of arsenic pollution treatment, and particularly relates to an enhanced treatment method for acidic arsenic-containing wastewater. According to the carbonate mineral enhanced crystallization treatment method for the acidic arsenic-containing wastewater, on the basis of the structural compatibility between carbonate minerals and calcium arsenite minerals, the calcium arsenite minerals are induced to be subjected to epitaxial crystallization and mineralization by utilizing the interface action of the carbonate minerals. Compared with the technical method without carbonate mineral induction, the Ca-As (III) product obtained by the technical scheme has better crystallinity, larger crystal size and lower solubility, so that the removal of As (III) in the wastewater can be enhanced.

The invention relates to the technical field of hazardous waste treatment, in particular to a method for safely treating hazardous waste containing phosphorus and arsenic, simple substance phosphorus and arsenite are oxidized in two stages through sodium hypochlorite, then phosphate and arsenate are converted into calcium phosphate, calcium arsenate and iron arsenate precipitates, stabilization of phosphorus and arsenic is achieved, and the hazardous waste containing phosphorus and arsenic is obtained. Finally, flocculation, solid-liquid separation and solidification landfill are conducted, and safe treatment of phosphorus and arsenic is achieved.

The application belongs to the field of arsenic pollution treatment, and more particularly relates to a method for enhanced treatment of acidic arsenic-containing wastewater. The application provides a method for carbonate mineral enhanced crystallization treatment of acidic arsenic-containing wastewater, which is based on the structural compatibility between carbonate minerals and calcium arsenite minerals, and uses the interface effect of carbonate minerals to induce the epitaxial crystallization of calcium arsenite minerals into minerals. Compared with the technical method without carbonate mineral induction, the Ca-As(III) product obtained by the technical solution has better crystallinity, larger crystal size and lower solubility, so that the removal of As(III) in the wastewater can be enhanced.

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 application relates to the technical field of biomedical engineering, and discloses a sodium alginate hydrogel loaded with copper arsenite nanoparticles as well as a preparation method and application thereof. The hydrogel comprises a sodium alginate hydrogel matrix and copper arsenite nanoparticles loaded therein, the copper arsenite nanoparticles comprise Cu2+, arsenite ions and PLGA-PEG-NH2, the sodium alginate hydrogel loaded with the copper arsenite nanoparticles is used for in-situ solidification to form a drug storage after intratumoral injection. The application constructs a nanoparticle self-assembly system based on PLGA-PEG-NH2, uniformly loads a complex formed by arsenite ions and copper ions in the PLGA-PEG-NH2 carrier material, forms copper arsenite nanoparticles with uniform and controllable particle sizes through a self-assembly process, the nanoparticles form stable complexes through coordination complexation between Cu2+ and As3+, and have the characteristics of specific dissociation in a tumor acid microenvironment.

The invention relates to a method for producing scorodite from a solution comprising arsenic and sulfuric acid without the use of a neutralizing agent, comprising the following steps: i. Subjecting a first arsenic solution comprising arsenic and sulfuric acid in the form of a mixture of arsenite ions and arsenate ions to an oxidation treatment, oxidizing the arsenite ions into arsenate ions, a second arsenic solution is obtained; ii, adding a first solution containing ferrous ions into the second arsenic solution to generate a third arsenic solution; iii. Adding a first portion of magnetite to the third arsenic solution to adjust the molar ratio of iron ions to arsenate ions to 0.3-1 to generate a first arsenic slurry; iv. Adding to the first arsenic slurry a portion of the scorodite slurry recycled from step viii as a nucleation matrix for scorodite particles, obtaining a first scorodite slurry of from 2% w / w to 15% w / w; v, heating the first scorodite slurry to 80 DEG C to 90 DEG C; vi, the first scorodite slurry is kept at the temperature of 80 DEG C to 90 DEG C for 5 h to 48 h, and second scorodite slurry is obtained; vii, conveying the second scorodite slurry to a solid-liquid separation step to obtain third scorodite slurry and a treated solution; viii. Recycling a first portion of the third scorodite slurry to step iv; and (ix) filtering a second portion of the third scorodite slurry.

The invention discloses a method for recovering metal from low-nickel copper fire refining slag and application, and relates to the technical field of metal metallurgy. Comprising the following steps: carrying out alkaline arsenic leaching on the copper fire refining slag to obtain leached slag and arsenic-containing liquid, carrying out arsenic removal on the arsenic-containing liquid by adopting a calcium salt precipitation method to obtain calcium arsenite and arsenic-removed liquid, and carrying out medium-temperature roasting on the calcium arsenite to obtain basic calcium arsenate; and leaching residues are subjected to reduction smelting to recover copper. The separation of copper and arsenic in the raw materials is realized by adopting alkaline arsenic leaching, the content of arsenic in the leaching residues is reduced, and when copper recycled from the leaching residues is introduced into a copper electrolysis process, the problem of arsenic accumulation in electrolyte purification is relieved, and the purification cost of the electrolyte is reduced. Besides, the arsenic-containing liquid is treated by adopting a calcium salt precipitation method to obtain calcium arsenite precipitates, so that rapid separation of arsenic elements is realized, the calcium arsenite precipitates are subjected to medium-temperature roasting, basic calcium arsenate with lower toxicity and better stability is obtained, and harmless and stable treatment of arsenic is realized.

The utility model relates to a device for preparing high-purity arsenic, which comprises an electrode reaction tank, the electrode reaction tank comprises an anode plate, a cathode plate and a power supply, the anode plate and the cathode plate are arranged in the electrode reaction tank, the power supply is electrically connected with the anode plate and the cathode plate, and an oxygen outlet and an arsenious acid inlet are sequentially arranged on the side wall of the electrode reaction tank close to the anode plate from top to bottom. An arsenic hydride discharge port is formed in the upper part of the side wall, close to the cathode plate, of the electrode reaction tank; the arsenic hydride discharge port is connected with a tubular heater, an outlet of the tubular heater is connected with a condensation collecting tank, and an outlet of the condensation collecting tank is connected with a hydrogen peroxide washer. According to the device, the electrode reaction tank, the tubular heater and the condensation collection tank are connected to form the high-purity arsenic preparation device adopting the electrode and thermal decomposition method, and the device can be used for preparing high-purity arsenic, can be used for efficiently recovering arsenic elements in arsenide waste residues generated in the metallurgical process, and fully realizes resource recycling.

The invention relates to a method for repairing arsenic-polluted soil. The method comprises the following steps that S1, a first positive electrode and a first negative electrode are inserted outside a to-be-repaired soil area; an electrolyte is applied to the soil area around the negative electrode; the first positive electrode and the first negative electrode are communicated with a power supply; after electrifying for 10 to 14 hours, standing for 10 to 14 hours; s2, exchanging electrodes; continuously electrifying for 10 to 14 hours, and standing for 10 to 14 hours; s3, detecting the content of pentavalent arsenic in the soil, and if the content is less than 85%, repeating the steps S1 and S2; and if the concentration is greater than 85%, removing the No.1 positive electrode and the No.1 negative electrode, and inserting the No.2 positive electrode and the No.2 negative electrode at the original electrode position. According to the method, the oxidizing agent is injected into the soil through electroosmosis, and trivalent arsenic in the soil is oxidized into pentavalent arsenic easy to stabilize; ferrous ions are introduced into the soil by utilizing the sacrificial positive iron electrode and are subjected to adsorption-precipitation reaction with arsenite and arsenate, so that the aim of stabilizing the arsenic-polluted soil is fulfilled.

The invention discloses an arsenic-containing wastewater treatment method and system, and belongs to the technical field of wastewater treatment. A two-stage'hydrogen peroxide and ferrite 'arsenic removal treatment method is adopted, lime is added into the wastewater firstly, the pH of the wastewater is increased, and calcium arsenite and calcium arsenate salt precipitates are generated through reaction of calcium ions and arsenic in water; the method comprises the following steps of: adding ferrous salt and hydrogen peroxide into wastewater, oxidizing most of Fe < 2 + > in the wastewater into Fe < 3 + > and As < 3 + > into As < 5 + > through sufficient aeration oxidation to generate calcium arsenate / iron and calcium arsenate / iron slag precipitates with lower solubility, removing arsenic through filtration, and discharging after reaching the standard. The method is low in operation cost, convenient to operate, easy to implement, environmentally friendly and free of secondary pollution. According to the invention, the precipitation efficiency, the arsenic removal stability and the standard-reaching rate of water quality are greatly improved, the environmental protection pressure of enterprises is effectively reduced, the environment is better protected, and the method has great social, economic and environmental significance.