68 results about "Ferrihydrite" patented technology

The invention discloses an advanced municipal wastewater treatment system and method, which are designed to solve the problems that sewage treated by using the prior art can not achieve the specified national standard, the flow is long, the occupied area is large, the running cost is high and the like. The advanced municipal wastewater treatment system comprises a grill sewage treatment device, a grit chamber, an anoxia pool, an MBR (Membrane Bioreactor) aerobic biofilter, an adsorption filter internally filled with a composite nano ferrihydrite adsorbent, and a disinfecting tank which are communicated in sequence, wherein a sludge outlet for exhausting sludge is arranged at the bottom of the MBR aerobic biofilter. The advanced municipal wastewater treatment method comprises the steps of: removing suspension matters with the grill sewage treatment device, settling inorganic particles with the grit chamber, carrying out denitrification treatment, carrying out advanced purification treatment by an MBR membrane component, carrying out dephosphorization with the composite nano ferrihydrite adsorbent, and carrying out disinfection treatment on the water treated by the above steps, wherein a part of sludge subjected to advanced purification treatment by the MBR membrane component flows back into the denitrification treatment.

A treating material for treating a polluted water containing, as a hazardous substance, arsenic, lead, cadmium, antimony, uranium, phosphorus, fluorine or the like, which comprises an oxygen-containing iron compound carried on a material containing a silicic acid based fiber or a silicate based fiber; a method for producing the treating material which comprises contacting and reacting a silicate based fiber, such as rock wool, with an iron-containing acidic water; and a method for treating the polluted water witch comprises contacting the treating material with the polluted water. The treating material has a fine structure wherein the above oxygen-containing iron compound is attached in a sheath form on the surface of a fiber reduced in an alkali component and increased in a silicic acid component as compared to, for example, rock wool. The oxygen-containing iron compounds include schwertmannite, ferrihydrite, akaganeite, amorphous hydrous iron oxide and fired ferric sulfate.

This invention relates to a method of manufacturing an organic-inorganic composite hybrid adsorbent by impregnating activated carbon nanopores with an oxide and a water treatment method using the same, and particularly, to an adsorbent including a porous adsorbent and ferrihydrite, goethite, hematite or magnetite incorporated into the porous adsorbent, and a manufacturing method thereof.

The invention relates to a preparation method used for forming an arsenic/fluorine-removing adsorbent, which comprises the following steps of: (a) adding polyvinyl alcohol into water at normal temperature while stirring, raising temperature and stirring to completely dissolve the polyvinyl alcohol, and then cooling to room temperature; (b) adding a carboxylic acid solution into a polyvinyl alcohol solution while stirring, carrying out esterification reaction, and cooling an esterification product solution to room temperature for standby; and (c) adding the esterification product solution intoadsorbent goethite, sulfate aka-ganeiteor ferrihydrite powder and uniformly mixing, extrusion-forming to obtain wet particles, then carrying out crosslinking treatment and drying to obtain an arsenic-removing adsorbent; or adding the esterification product solution into oxyhydroxide powder and uniformly mixing, extrusion-forming to obtain wet particles, then carrying out crosslinking treatment and drying to obtain a fluorine-removing adsorbent. The prepared adsorbent particles have the characteristics of high strength, toughness, less adsorption capacity loss in the forming process without swelling, and the like.

The invention relates to a chemical-biological passivator and a preparation method thereof. The preparation method comprises the following steps: uniformly mixing ferrihydrite with carbon residue powder to obtain a mixture; adding the mixture into a bacterial suspension of acanthosporum, the bacterial content of which is 1.0-9.9*10<7>cfu/ml. The chemical-biological passivator provided by the invention is obviously enhanced in promoting growth of water spinach, can reduce arsenic absorption by water spinach and reduce effectiveness of soil arsenic, and can be used as an efficient chemical-biological passivator for regulating arsenic pollution farmland risk in the future.

The invention discloses a method for deep dephosphorization of wastewater by using siderite as a sand filter filtering material. The method is characterized by comprising the steps of crushing and screening natural siderite ore to obtain 0.25-0.5mm particles, filling a sand filter by using the particles as filler, and carrying out deep dephosphorization on low-concentration phosphorus wastewater via a filter manner. The principle is that the siderite is slowly oxidized by the dissolved oxygen in the water to form newly born ferrihydrite (iron hydroxide) and the newly born ferrihydrite adsorbs to remove the phosphor in the water. Through regular back washing, the ferrihydrite membranes on the surfaces of the particles fall off, so that the oxidization dephosphorization of the siderite is restored. The method provided by the invention is suitable for the deep dephosphorization of domestic wastewater, landscape water and polluted river water.

The invention provides an iron-based catalyst for strengthening ozone oxidation of organic pollutants. The catalyst can efficiently catalyze the organic pollutants which are difficult to degrade by the ozone oxidation under the condition of low ozone concentration to remove difficultly degraded organic substances, and is prepared by taking natural zeolite, artificial zeolite or a zeolite-like material as a carrier loaded with active components, wherein the active components comprise ferrihydrite and delta-hydroxyl oxidize iron in a mass ratio of (20 to 80): (20 to 80); the invention further provides a preparation method of the catalyst and a method for treating wastewater by using the catalyst which can effectively remove antibiotics such as metronidazole difficult to degrade in hospital wastewater; furthermore, the invention improves a disinfection device of existing hospital wastewater, namely a filling layer of the iron-based catalyst is added in an ozone contact pool, thereby not only disinfecting wastewater, but also decomposing the antibiotics in wastewater without changing original operating parameters.

The invention discloses a modified ferrihydrite/hematite nano-rod core-shell structure compound light anode and an application thereof. A preparation method of the light anode includes the steps: S1 preparing hematite growth solution, placing a conducting substrate into the hematite growth solution, synthesizing a FeOOH film on the conducting substrate by a solvent thermal synthesis method, washing the FeOOH film, and drying the washed FeOOH film for standby application; S2 performing high temperature annealing on the conducting substrate acquired in the step S1, and cooling the conducting substrate to obtain the conducting substrate with the hematite film surface; S3 preparing ferrihydrite growth solution, placing the conducting substrate acquired in the step S2 into the ferrihydrite growth solution, heating mixture, washing the conducting substrate after reaction is completed, and drying the washed conducting substrate to obtain the modified ferrihydrite/hematite nano-rod core-shellstructure compound light anode. According to the method, a ferrihydrite thin layer is loaded on the surface of the hematite to prepare the core-shell structure compound light anode which is resistantto light corrosion and good in photoelectrochemical property and stability, and the compound light anode can be used for decomposing water to generate hydrogen and is high in catalytic efficiency andstable in catalytic effect.

The invention discloses a hollow cerium dioxide microsphere supported ferrihydrite heterogeneous Fenton-like catalyst and a preparation method and application thereof. The preparation method of the hollow cerium dioxide microsphere supported ferrierite heterogeneous Fenton-like catalyst comprises the following steps: firstly, preparing porous cerium dioxide nanospheres by using Saccharomyces cerevisiae as a biological template in a high-temperature environment; and then, loading the porous cerium dioxide nanospheres on the surface of ferrierite by in-situ deposition. The mesoporous ceria nanospheres in the catalyst have a photosensitive effect, can generate photo-generated carriers in response to visible light, and promote the activation efficiency of the ferrihydrite on hydrogen peroxide in a Fenton system. Generated active free groups have broad-spectrum catalytic degradation effect on pollutants and have certain practical application value.

The invention discloses a method for reducing arsenic absorbed by crops. The method comprises the following steps: an aperture disk which is 50-55cm long and 25-30cm wide is selected to serve as a seedling-raising disk, the seedling-raising disk comprises 28-34 apertures, and each aperture has a diameter of 5-7cm and is 9-10cm deep; 60%-65% of grass charcoal, 25-30% of vermiculite, 5-7% of magnesia-alumina bimetallic oxide and 3-5% of ferrihydrite are mixed in percentage by weight; 1-2kog of nitrgen, phosphorus and potassium ternary compound fertilizers are added into 100kg of mixtures and are uniformly mixed to form seedling substrates; 35-40% of water is sprayed onto the seedling substrates in percentage by weight, and then the seedling substrates are aired for 2-3 days in shades; the seedling substrates are put into the selected aperture disk, and the seedling substrates in each aperture are leveled; seeds sown in each aperture are covered with a few seedling substrates, and then water is sprayed until the water seeps out of small holes in the bottoms of the apertures. After the method is used in farmland with excessive arsenic, the arsenic accumulated in the crops can be obviously reduced.

The invention discloses a method for preparing a sintering ore from high-crystallite ferrihydrite powder. The method includes the following steps of firstly, preparing a raw material from, by mass, 75-90% of iron powder, 3.5-8.5% of limestone, 0-4% of light-burned dolomite, 1.5-2.5% of serpentine, 3.0-4.5% of quick lime and 4.5-6.0% of coke powder; secondly, adding water to the raw material to bemixed to obtain a mixture, and performing granulating to obtain granules; and thirdly, performing distributing, igniting and sintering on the granules to obtain the sintering ore. The obtained sintering ore has the alkalinity of 1.95-2.05, the MgO mass percentage of 1.90-2.10% and the tumbler strength of larger than or equal to 65.8%, can be effectively used for production in a blast furnace, andensures the long-term smoothness of the production in the blast furnace.

The invention discloses a preparation method and application of functionalized nanometer ferrihydrite. The preparation method comprises weighing powder of leaves of Excoecaria cochinchinensis Lour, carrying out ultrasonic concussion to obtain extract of leaves of Excoecaria cochinchinensis Lour, adjusting pH of the extract, adding a ferric chloride solution into the extract, carrying out ultrasonic concussion for a reaction, and carrying out suction filtration and washing to obtain nanometer ferrihydrite. The nanometer ferrihydrite has significant adsorption effects on heavy metals and acid and basic dyes. The method utilizes eco-friendly raw materials, realizes a low cost, has no pollution to the environment and has high removal efficiency.

The invention relates to an Mg(OH)2-based phosphorus binding film as well as a preparation and an application thereof. With MgO powder as a binding agent, the MgO powder and water in a prepolymerization solution can react for in-situ hydration in an MgO polymerization process to form Mg(OH)2, so that the concentration of the prepolymerization solution is increased and the film-forming time is shortened; the Mg(OH)2-based phosphorus binding film is simple in preparation process and has the advantages of high film-forming rate, high mechanical strength, difficult deformation and uniform distribution of a phosphorus fixing agent in the film; meanwhile, the prepared Mg(OH)2-based phosphorus binding film can enrich low-concentration phosphorus in a water body, especially low-concentration phosphorus in seawater; compared with a commercial ferrihydrite-DGT (diffusive gradient in thin film) in-situ enrichment device, an Mg(OH)2-DGT in-situ enrichment device assembled by the Mg(OH)2-based phosphorus binding film is relatively high in capture capability on nanomole phosphorus in different water bodies, relatively accurate in determination result and relatively high in selectivity.

The invention discloses an iron-reducing comamonas and an application thereof. The inventor screens the iron-reducing comamonas with the humus reduction activity and the iron reduction activity by a great deal of experiments. The bacteria can reduce the ferric iron such as ironic citrate, iron hydroxide, ferrihydrite and goethite; and reduce the humus and the humic model AQDS (anthraquinone-2, 6-disulfonic acid). The iron-reducing comamonas is the facultative anaerobe, has wide electro donor spectrum. The electro donors which can be oxidized by the bacteria in the anaerobic condition are glycerine, glucose and sucrose.

This invention provides a method for preparing ultrafine alpha-Fe2O3. The method comprises: adding Ferrihydrite, delta-FeOOH, and one of amorphous alpha-FeOOH and gamma-FeOOH as crystal seeds to Fe in a neutral condition, adding Fe (II) as the catalyst, introducing air, and oxidizing at 90 deg.C to obtain ultrafine alpha-Fe2O3 crystal with purity higher than 98%. The particle sizes of the product are adjustable, and the dispersion is good. The method has such advantages as simple process and no pollution, and is suitable for industrialization.

The invention discloses a preparation method of magnetic nanocrystals with adjustable morphology. The preparation method comprises following steps: step 1, preparation of ferrihydrite precursors, wherein hydrolysis reaction is promoted by adding CuO into a Fe(NO3)3 solution so as to obtain the ferrihydrite (Fe5O7OH.4H2O) precursors; and step 2, preparation of the magnetic nanocrystals, wherein a mixture of the ferrihydrite precursors, a FeCl2 solution and a NaOH solution is subjected to heating processing so as to obtain the maghemite (gamma-Fe2O3) nanocrystals. Technological conditions of the preparation method is mild, raw material cost is low, and it is possible to obtain ball-shaped, rod-shaped or sheet-shaped magnetic nanocrystals by controlling the synthesis conditions.

The invention relates to a ferrihydrite (FH)-ultra-filtration (UF) membrane combination process for removing trivalent arsenic and dissolved organic matters (DOMs) in water, so as to control disinfection by-products (DBPs) and relieve membrane pollution, belonging to the technical field of water treatment. The process comprises the following steps: adding an adsorbent FH into a hollow fiber UF membrane filtration system, maintaining a suspension state by means of aeration, providing a shearing force to reduce the enrichment of pollutants on the surface of the membrane, and separating out the adsorbent from the water by means of UF membrane filtration. The process utilizes the trivalent arsenic to bond with monoatomic or diatomic O on the surface of FH, and simultaneously enables the FH andthe DOMs to be subjected to a coordination exchange reaction so as to form a coordination complex, so that 99.4% of the trivalent arsenic, 80.2% of a trihalomethane precursor and 90.4% of a haloacetic acid precursor are effectively removed, the concentrations of the arsenic and all the DBPs in effluent reach the drinking water standard, and the safety of drinking water is accordingly guaranteed.Furthermore, FH adsorption pretreatment reduces the enrichment of the DOMs on the surface of the membrane and the absorption inside membrane pores, so that the transmembrane pressure difference is reduced by 65.5%, and membrane fouling is significantly alleviated.

Belonging to the field of environmental pollution control, the invention provides an adsorbent for anion and cation adsorption and a preparation method thereof. Specifically, the preparation method includes the steps of: adding a lanthanum salt into a weakly acidic magnetite solution, and adding alkali to adjust the magnetite solution to alkaline, mixing the substances evenly, then conducting washing with water to neutral, and the carrying out dehydration, calcination and grinding. The adsorbent has a core-shell structure, and comprises a magnetic composite material and lanthanum hydroxide loaded to the composite material. The composite material includes ferrihydrite coated magnetite. The adsorbent provided by the invention has high efficiency adsorption capacity on anions and cations, also is low in preparation cost, and is easy for separation. The preparation method provided by the invention is simple and has low energy consumption, the prepared sample is magnetic and is easy to separate, at the same time, the preparation process is a liquid phase reaction process, has no need for harmful reagent, and is easy for large-scale preparation. And the adsorbent has wide application prospects in the field of pollution control.

The invention discloses Penicillium chrysogenum and ferrihydrite aggregate and a production method and application thereof, wherein the Penicillium chrysogenum and ferrihydrite aggregate is formed by wrapping ferrihydrite in hyphae of Penicillium chrysogenum by using Penicillium chrysogenum as a carrier; the production method includes the steps of culturing Penicillium chrysogenum into a bacterial suspension; preparing ferrihydrite from ferric nitrate; mixing the bacterial suspension and the ferrihydrite, and culturing by shaking to obtain the Penicillium chrysogenum and ferrihydrite aggregate; the Penicillium chrysogenum and ferrihydrite aggregate herein has low cost, high operability, high safety and high responding speed, is significantly effective in removing trivalent arsenic in wastewater, and is applicable to removing arsenic in wastewater.

The invention discloses a montmorillonite composite material and application thereof in adsorbing heavy metals. The montmorillonite composite material comprises montmorillonite and ferrihydrite, wherein the ferrihydrite is dispersed on the outer surface of the montmorillonite. The montmorillonite composite material disclosed by the invention has a relatively large BET specific surface area and a multi-stage pore structure characteristic, not only retains the pore structure characteristic of montmorillonite, but also has the pore structure characteristic of ferrihydrite; the ferrihydrite particles with positive charges and the montmorillonite particles with negative charges on the surface are firmly combined to form a stable montmorillonite composite material; and the composite material has typical structural characteristics of silicate minerals and ferrihydrite with a layered structure, and ferrihydrite nanoparticles are of a spherical particle structure and are wrapped by montmorillonite sheets. The montmorillonite composite material disclosed by the invention is applied to a water body or site soil environment containing various heavy metals, and the heavy metals in the environment can be effectively removed.

The invention discloses a preparation method of an amido-modified ferrihydrite material and an application thereof, and ferrihydrite is modified by using amido-rich polyethyleneimine with an iron element widely existing in nature as a raw material to obtain a chromium removal adsorbent with high adsorption capacity. The preparation method is a co-precipitation method and is environment-friendly, energy-saving and simple, the raw materials required by the preparation method are common, easy to obtain and non-toxic, and the obtained adsorbent has high performance on hexavalent chromium in wastewater and good cyclic utilization, and is a novel adsorbent for effectively treating the wastewater containing hexavalent chromium.

The invention provides a bacterial strain with iron reduction capacity and electrochemical activity and application thereof, and belongs to the technical field of microbial system classification and environmental biology. The bacterial strain with the iron reducing capacity and the electrochemical activity is named shewanella sp. C31, is preserved in Guangdong Microbial Culture Collection Center (GDMCC) of Institute of Microbiology, Guangdong Academy of Sciences, located on the fifth floor, No. 59, No. 100 Courtyard, Xianlie Middle Road, Guangzhou City on January 17, 2022, and has the preservation number of CDMCCNO: 62214. The strain with the iron reducing capacity and the electrochemical activity can grow in an anaerobic environment by using ferric citrate or ferrihydrite as an electron acceptor and sodium lactate as a unique electron donor, and has a relatively good electrogenesis effect in a bioelectrochemical system; the method has a wide application prospect in the aspects of environmental pollution repair and microbial electrochemical research.

The invention belongs to the field of heavy metal pollution repair, and provides a ferrihydrite@bone black material for synchronously fixing anion and cation heavy metal ions, wherein the ferrihydrite@bone black material comprises 8-20 wt% of a calcium element, 8-14 wt% of a phosphorus element, and 15-30 wt% of an iron element. The method comprises the steps: adding bone black into a ferric salt solution at normal temperature, stirring, adding a certain amount of sodium sulfate solid, stirring, slowly dropwise adding a sodium hydroxide solution until the pH value of the mixed solution reaches 8.0-8.5, and keeping a stirring state in the whole reaction process; and standing and stabilizing the system at room temperature for 12 hours, filtering to obtain a solid, and drying to finally obtain ferrihydrite composite biological hydroxyapatite. The preparation process is energy-saving, low in consumption, economical, practical, green and environment-friendly, the specific surface area of the material is enlarged, the surface property of the material is changed, and the material has an adsorption effect in a combined pollution environment and can synchronously fix various anion and cation heavy metals such as Pb (II), Cd (II) and AsO2<->.

The invention discloses a method for adsorbing heavy metals in wastewater by using aluminum-substituted ferrihydrite. High-concentration arsenic and cadmium are synergistically adsorbed and fixed by nanometer aluminum-substituted ferrihydrite respectively in an acidic environment and an alkaline environment by regulating the pH value, the concentration ratio of arsenic to cadmium and other conditions. An efficient nanometer aluminum-substituted ferrihydrite adsorbent can be synthesized from nontoxic and harmless common crustal elements, and the process is simple; the nanometer aluminum-substituted ferrihydrite has a good removal effect on co-existing arsenic, cadmium and other negative and positive heavy metal ions; the adsorbent also can simultaneously treat mercury, copper, zinc, antimony, bismuth and other heavy metals existing in the forms of negative and positive ions, besides the arsenic and cadmium; and the nanometer aluminum-substituted ferrihydrite synthesized through the process can be used to treat industrial and mining enterprise heavy metal wastewater, and also can be used in emergency heavy metal pollution events of environment water.

The invention belongs to the technical field of microorganisms, and particularly relates to a method for efficiently and directionally enriching and separating hydrogen producing bacteria and application of the hydrogen producing bacteria obtained through separation in hydrogen production and acetic acid and butyric acid production through fermentation. According to the method, after heat treatment is performed on activated sludge, an inducer amorphous ferrihydrite is added, and incubation is performed under an oligotrophic condition; an incubated culture is transferred into an MSG-rich culture medium containing the amorphous ferrihydrite for cultivation, passage culture continues to be carried out on a cultured product, and a product is a hydrogen producing enriched flora. The method forefficiently and directionally enriching and separating the hydrogen producing bacteria can achieve the efficient and convenient enrichment and separation of the hydrogen producing bacteria or strains,and has important guiding significance and broad application prospects in the industrial production process of microbial fermentation hydrogen production.