34 results about "Phosphate adsorption" patented technology

The invention belongs to the field of biochar adsorbing materials, and relates to a method for preparing modified biochar with aquatic plant waste and hematite. The method includes the following steps: (1) naturally drying aquatic plants prior to crushing to obtain aquatic plant powder; (2) crushing the hematite to obtain hematite powder; (3) weighing the hematite powder prior to putting the hematite powder into deionized water, and performing ultrasonic treatment to obtain suspension; (4) weighing the aquatic plant powder, soaking the aquatic plant powder in the suspension, and stirring and drying to obtain fully mixed aquatic plant and hematite mixture; (5) weighing the fully mixed aquatic plant and hematite mixture, putting the mixture in a batch-type atmosphere furnace, and feeding nitrogen into the furnace; performing temperature programming to the target temperature, and maintaining final-temperature pyrolysis; after the pyrolysis process is finished, obtaining the target product, namely the modified biochar. The modified biochar has strong adsorbability in nitrate and phosphate, high in stability and reusable.

The invention discloses a lake eutrophication biological treatment system and a dynamic method based on multi-dimensional cooperative regulation and control. Exogenous pollution control, layered biological manipulation and artificial intelligence dynamic feedback are fused, and the method is particularly suitable for moderate eutrophication water bodies with nitrogen and phosphorus exogenous input not completely cut off. According to the gradient filling structure, macromolecular organic matters are intercepted by using shallow coarse particles, and middle / fine particles specially attack phosphate adsorption, so that graded removal of pollutants is realized; fish ingestion and benthic organism disturbance have a synergistic effect, secondary pollution of aquatic plant litter degradation to a water body is reduced, transfer of nitrogen and phosphorus from the water body and plant litters to animal objects is promoted, and the coupled system can reduce the phosphorus release rate of bottom mud, improve the stability of FePO4 precipitation and synchronously degrade sulfides and organic matters in the bottom mud; electric shock damage to benthic organisms is avoided through the micro-current intensity, sulfur metabolites can be used as a nutrient source of submerged plants, and biological self-purification and resource utilization of eutrophic water are achieved.

The invention discloses ferric chloride and calcium chloride combined modified biochar, a preparation method thereof and a method for enhancing phosphate adsorption, and the preparation method comprises the following steps: (1) mixing and dipping original biochar with a ferric chloride and calcium chloride solution, and fully shaking and shaking up the mixed solution; (2) carrying out suction filtration on the mixed solution to remove supernate, and drying residual solid substances to obtain a modified biochar material; and (3) putting the modified biochar material into a tubular furnace, continuously introducing nitrogen into the tubular furnace, carrying out high-temperature carbonization at 600 + / -5 DEG C for 2 + / -0.1 h, cooling the tubular furnace to room temperature, taking out, cleaning, and drying to obtain the biochar jointly modified by ferric chloride and calcium chloride. Adsorption active sites of the biochar can be increased after joint modification of ferric chloride and calcium chloride, the specific surface area of the biochar is increased, the structure of the biochar is looser, and the adsorption effect is enhanced.

This invention relates to a highly efficient functional ceramsite for purifying phosphorus-containing wastewater, its preparation method, and its application. Based on a complementary functional strategy, it uses natural clay rich in Al2O3 and SiO2 as a binder and calcium-rich industrial solid waste as the calcium-rich active component. Functional additives are also added to mitigate pH changes caused by calcium oxide reactions. The above raw materials are calcined at high temperature to obtain inexpensive, calcium-rich functional ceramsite with high mechanical strength, large adsorption capacity, and ecological safety. This effectively solves the common problems of increased water pH and poor phosphate adsorption capacity at neutral pH in calcium-based ceramsite, achieving highly efficient phosphorus purification in water. This invention uses inexpensive and readily available natural clay and calcium-rich industrial solid waste as raw materials, resulting in low cost, good effect, and effective application in the treatment of low-pollution water.

The invention provides a phosphate adsorption material and a preparation method thereof. The phosphate adsorbent material comprises: an inner core containing one of a metal compound and a metal silicate; an outer shell for covering the inner core, the outer shell comprising a composite metal oxide or a composite metal hydroxide; the inner core and the outer shell jointly form the phosphate adsorption material with the core-shell structure, the porous framework is of a monolithic integral structure, and the phosphate adsorption material with the core-shell structure is embedded in the porous framework. The adsorption material disclosed by the invention can be used for deeply removing phosphate in water pollution treatment.

The invention belongs to the technical field of sewage treatment equipment, and particularly relates to a high-spinning-state sulfur-ferrihydrite adsorption material for a fixed bed, a preparation method and fixed bed adsorption equipment. According to the high-spin-state sulfur-ferrihydrite adsorption material for the fixed bed, in the preparation process, through the weak field ligand effect of sulfur, a FeO6 octahedron of ferrihydrite is triggered to generate remarkable Taylor (Jahn-Teller) distortion, Fe < 3 + > is induced to be converted into a high-spin state, spin polarization is regulated and controlled, part of low-spin-state Fe < 3 + > ions are promoted to be converted into the high-spin state, and the high-spin-state sulfur-ferrihydrite adsorption material for the fixed bed is obtained. The high-spin-state sulfur-ferrihydrite is obtained, the affinity with phosphate is enhanced, and the phosphate adsorption performance of the ferrihydrite is improved at present; the high-spinning-state sulfur-ferrihydrite is filled into fixed bed adsorption equipment, so that pollution of wastewater and sewage discharge to natural water bodies such as underground water, rivers and oceans can be effectively reduced, and the phenomena of algae bloom and red tide are avoided.

The invention provides a lanthanum modified magnetic nano carbon adsorbent as well as a preparation method and application thereof, and belongs to the technical field of water treatment. The method comprises the following steps: performing catalytic pyrolysis on biomass by Fe < 3 + > to form hierarchical porous biochar; epitaxially growing a Fe3O4 magnetic layer by a hydrothermal method; carrying out free radical polymerization grafting on poly (1-vinyl imidazole); and La < 3 + > coordination loading and alkali activation. When 0.03 g / L (pH is 3-4) of the obtained adsorbent is added into phosphorus-containing wastewater, the 30-min phosphate removal rate is larger than or equal to 94%, the Langmuir adsorption capacity is larger than or equal to 117.32 mg P / g, and the adsorption retention rate is larger than or equal to 90% and the La dissolution rate is smaller than or equal to 0.2% after five times of circulation. According to the lanthanum modified magnetic nano-carbon adsorbent as well as the preparation method and the application thereof, lanthanum modification is performed on the magnetic nano-carbon, so that the obtained lanthanum modified magnetic nano-carbon adsorbent has the advantages of high adsorption capacity on phosphate in a water body, good selectivity, high removal rate, easiness in separation and recovery, small mass loss, no dissolution, no secondary pollution problem and the like.

A biomass / iron-based organic framework composite and a preparation method and use thereof are provided. The preparation method includes: adding chitosan, an iron-based organic framework MIL-88(B), and a crosslinking agent to an acetic acid solution, thoroughly mixing, and heating in a water bath; and adding a mixed solution dropwise, and allowing a reaction to produce the biomass / iron-based organic framework composite. The biomass / iron-based organic framework composite prepared by the present disclosure has a phosphate adsorption capacity of 1.1 mmol / g, which is higher than the corresponding adsorption capacities of a pure iron-based organic framework material and a pure biomass-based material. Under the optimal adsorption pH condition, a loss of an iron-based organic framework material is less than 1%.

The invention discloses a phosphate adsorbent with a rod-like structure as well as a preparation method and application thereof, and relates to the technical field of sewage treatment materials. According to the preparation method of the phosphate adsorbent, the molar ratio of magnesium nitrate to sodium carbonate to sodium hydroxide in the reaction process is specifically controlled, so that the generated reaction product is a mixture of magnesium carbonate and magnesium hydroxide in a specific ratio, and the magnesium carbonate and the magnesium hydroxide can be calcined according to different decomposition temperatures of the magnesium carbonate and the magnesium hydroxide during calcination. Through targeted adjustment of a calcination process, the calcination process and a reaction product can achieve a synergistic effect, and the number, distribution and pore size of pores in the rodlike porous magnesium oxide are remarkably improved, so that the specific surface area and oxygen vacancy of the obtained rodlike porous magnesium oxide are remarkably improved, and then the adsorption capacity and efficiency of phosphate are remarkably improved; the adsorbent is suitable for large-scale application as a phosphate adsorbent; the preparation method is simple in step, controllable in process, stable in product performance and suitable for large-scale production of the phosphate adsorbent with the rod-like structure.

The application provides a flexible MOF microfiltration membrane and a preparation method and application thereof, and belongs to the technical field of polymer composite membranes. The polymer nanofiber membrane formed by polymer nanofibers has a large specific surface area, so that the flexible MOF microfiltration membrane has a larger contact area with pollutants. Meanwhile, the defective MOF particles are uniformly distributed on the surface of the polymer nanofibers of the polymer nanofiber membrane, and the defective MOF nanoparticles provide abundant active sites, which can improve the adsorption capacity for pollutants. The results of the examples show that the flexible MOF microfiltration membrane provided by the application has an adsorption capacity for phosphate which is about 50% higher than that of MOF particles, and the terephthalic acid leaching rate in the adsorption process is reduced from 12.0% to 0.3%.

The invention discloses a sodium citrate-based composite dephosphorizing agent and a preparation method thereof, the sodium citrate-based composite dephosphorizing agent comprises a calcium chloride mother solution, a PAC mother solution, a sodium citrate mother solution and a diluent, and the mass ratio of the calcium chloride mother solution to the PAC mother solution to the sodium citrate mother solution is 9: (0.5-1.5): (0.5-1.5); compared with the prior art, the method has the advantages that the calcium chloride mother liquor is adopted to provide a core calcium source, rapid saturation of Ca < 2 + > in the solution is ensured by the ultrahigh solubility of the calcium chloride mother liquor, the PAC mother liquor is matched to serve as a flocculation enhancer to provide strong current neutralizing capacity, and a'precipitation-complexing-flocculation 'triple synergistic system is constructed according to the adding proportion of the calcium chloride mother liquor, the PAC mother liquor and the sodium citrate mother liquor; the pH application range of the dephosphorizing agent is widened, the phosphate removal efficiency is remarkably improved, the synergistic effect of precipitation and complexation is enhanced, and the calcium-phosphorus precipitation effect and the phosphate adsorption capacity are synchronously improved.

The invention relates to the technical field of adsorption materials, and particularly discloses a lanthanum-modified iron tailing-based phosphate-removing adsorption material and a preparation method thereof. The lanthanum element is used for modifying the iron tailings, lanthanum chloride is adopted as a modifier, and the structure and surface performance of the material are optimized. After lanthanum modification, the specific surface area and the adsorption capacity of the iron tailings are remarkably improved, and phosphate in water can be effectively removed. Through reasonable design of a preparation process, the lanthanum modified iron tailing-based phosphate-removing adsorbing material prepared by the invention not only has relatively high adsorption performance, but also has relatively high stability, and is suitable for large-scale water body pollution treatment.

The invention provides modified biochar for selectively removing phosphate in sewage and sewage treatment.The modified biochar is prepared through the following method that after a biomass material is subjected to pyrolysis carbonization to form biochar, the biochar and ferric salt are subjected to chemical precipitation, and magnetic biochar is obtained; the preparation method comprises the following steps: carrying out coupling modification on magnetic biochar through an amino silane coupling agent to form aminated magnetic biochar, carrying out a Schiff base reaction on the aminated magnetic biochar and hydroxaldehyde, and adding lanthanum salt to carry out an in-situ complexation reaction so as to obtain the modified biochar. According to the modified biochar for selectively removing the phosphate in the sewage and sewage treatment, the biochar is subjected to iron and lanthanum modification, and the obtained modified biochar has the advantages of being high in adsorption capacity on the phosphate in a water body, good in selectivity, high in removal rate, easy to separate and recycle, small in mass loss, free of dissolution, free of secondary pollution and the like.

The invention belongs to the technical field of water treatment, and particularly relates to a rare earth element doped ferrihydrite adsorbent with the surface modified with betaine and a preparation method and application thereof.The adsorbent takes the rare earth element doped ferrihydrite as a matrix, the surface of the ferrihydrite is modified with betaine molecules, and an organic-inorganic hybrid structure is formed; at least one rare earth element is doped in the ferrihydrite, and the doping amount of the rare earth element in the ferrihydrite is 0.5-20wt%; the mass percentage of the betaine molecules in the adsorbent is 1-20wt%. Compared with the prior art, the invention solves the problem that the phosphorus adsorption material in the prior art is difficult to give consideration to high adsorption capacity, high selectivity, good dispersibility and long-term stability at the same time. According to the scheme, rare earth doping and betaine surface modification are combined to synergistically realize comprehensive improvement of the adsorption capacity, selectivity and complex water body interference resistance of the adsorbent on phosphate.

Pollution by phosphates affect aquatic life as they have side effects even at very low concentrations. Silica molybdate is prepared by first chlorinating silica sand using phosphorous pentachloride to give chlorinated silica which is aminated using ethylenediamine and thereafter treated with sodium molybdate. The molecular structure of the silica molybdate was characterized using Fourier Transform Infrared (FT-IR). FT-IR results showed Adsorption bands at 854cm-l and 542cm-l which were attributed to Mo=O and Mo-O stretching in molybdate. Peaks observed at 1388 and 1662cm-1 were attributed with the vibration mode of Mo-OH bond and bending mode of adsorbed water. Spectra peaks observed at 542, 634.58 and 898.97 cm-1 were attributed to the adsorption of molybdate. The physical adsorption parameters which were examined using batch adsorption system were; temperature, pH, contact, time, initial concentration using sorption models, adsorption kinetics and thermodynamics. Results showed that optimum pH for biosorption of P042- was 6.0, optimal contact time was 30 minutes, optimum temperature was 45°C. The experimental results obtained showed that the maximum phosphate adsorption of silica molybdate at optimum conditions was found to be 94.73% in water.

The invention relates to a preparation method and application of a double-defect Mg-MOF derivative metal oxide, and the preparation method comprises the following steps: dissolving DHTA, H3BTC or AA and MgNO3. 6H2O in DMF, EtOH and deionized water to form a mixed solution; carrying out high-temperature treatment on the mixed solution, collecting crystals, and washing for later use; and calcining the crystals at a high temperature to obtain a nano metal oxide which has oxygen defects and magnesium defects and is used for adsorbing and removing phosphate in wastewater. Nano magnesium oxide is generated through calcination by adopting an Mg-MOF sacrificial template method, meanwhile, high-concentration oxygen defects and high-concentration magnesium defects are achieved, particularly, nano metal oxide prepared by adopting AA further forms slit-type long and thin holes to expose more binding sites, and through the adsorption mechanism of ligand exchange, inner sphere complexing and electrostatic attraction, the nano magnesium oxide can be used for preparing the nano magnesium oxide with the high-concentration oxygen defects and the high-concentration magnesium defects. And the adsorption capacity is far higher than the adsorption capacity of the existing adsorbent on the phosphate, so that the adsorbent has practical application potential and relatively high application and popularization value.

A biomass / iron-based organic framework composite and a preparation method and use thereof are provided. The preparation method includes: adding chitosan, an iron-based organic framework MIL-88(B), and a crosslinking agent to an acetic acid solution, thoroughly mixing, and heating in a water bath; and adding a mixed solution dropwise, and allowing a reaction to produce the biomass / iron-based organic framework composite. The biomass / iron-based organic framework composite prepared by the present disclosure has a phosphate adsorption capacity of 1.1 mmol / g, which is higher than the corresponding adsorption capacities of a pure iron-based organic framework material and a pure biomass-based material. Under the optimal adsorption pH condition, a loss of an iron-based organic framework material is less than 1%.

The invention relates to the technical field of environmental functional materials, and particularly discloses sewage treatment rubber balls with microorganisms embedded in an MgFe-LDO / AC composite material as well as preparation and application of the sewage treatment rubber balls. Activated carbon is subjected to acid pickling and high-temperature calcination to form a porous carrier, MgFe-LDO is loaded through a hydrothermal synthesis method to construct a composite material, and a bacterial-algae symbiotic system and a sodium alginate gel embedding technology are combined to prepare the composite functional rubber ball. Compared with a common immobilized rubber ball, the rubber ball has the phosphate adsorption memory effect of MgFe-LDO and the NH4 < + > adsorption performance of activated carbon, is especially suitable for a decentralized sewage treatment system with low C / N ratio and high load fluctuation, and provides an efficient and stable solution for synchronous nitrogen and phosphorus removal.

The invention belongs to the technical field of water treatment, and particularly relates to a hydrogel loaded betaine modified rare earth element doped ferrihydrite adsorbent and a preparation method and application thereof, the adsorbent comprises an active component dispersed and fixed in a gel skeleton; the active component is ferrihydrite doped with rare earth elements, the surface of the ferrihydrite is modified with betaine molecules, the mass percentage of the betaine molecules in the active component is 1-20 wt%, and the doping amount of the rare earth elements in the ferrihydrite is 0.5-20 wt%; the gel skeleton is a hydrogel network formed by crosslinking sodium alginate and chitosan through divalent or trivalent metal ions. Compared with the prior art, the problem that an existing phosphate adsorbent is improved only aiming at single performance and lacks integrity improvement is solved. According to the scheme, the rare earth element doped ferrihydrite nano adsorbent of which the surface is modified by betaine is loaded in a natural polymer hydrogel network, so that advantage complementation and synergistic interaction of active components and structural frameworks are realized.

This invention provides an electrochemically regulated phosphate adsorption-desorption method, comprising: 1) Phosphate adsorption: a first electrolytic cell using a tetravalent cerium electrode as the cathode and phosphorus-containing wastewater as the electrolyte for a first electrolytic treatment; after the first electrolytic treatment is completed, the circuit is disconnected; and after the phosphorus concentration in the phosphorus-containing wastewater remains constant, phosphorus-free purified water and a trivalent cerium-phosphorus enriched electrode are obtained; 2) Phosphate desorption: a second electrolytic cell using a trivalent cerium-phosphorus enriched electrode as the anode for a second electrolytic treatment; after the second electrolytic treatment is completed, the circuit is disconnected; and after the phosphorus concentration in the electrolyte of the second electrolytic cell remains constant, a tetravalent cerium electrode and a phosphorus-rich recovery solution are obtained; the time for both the first and second electrolytic treatments is greater than 900 s. This method offers high process flexibility, a wide range of desorption solutions, and can achieve phosphate desorption in low-concentration desorption solutions, exhibiting high phosphate removal and recovery rates, as well as excellent cyclic adsorption-desorption performance.

The application provides a preparation and application of a porous lanthanum-based metal organic framework La MOF-X-C adsorbent. The preparation comprises: taking La(NO3)3.6H2O and two ligands of H2BDC and NH2-BDC, wherein the mass percentage of NH2-BDC in the total mass of the two ligands is X, and the value range of X is 5% to 30%; after being transferred into a high-pressure reaction kettle, the mixture is subjected to ultrasonic treatment in a beaker, reaction, cooling and the like to collect powder, and the powder is placed into a quartz crucible and calcined in a muffle furnace at 350 DEG C for 7 h to remove NH2-BDC in the ligand and obtain the La MOF-X-C adsorbent. Preferably, the mass percentage X is 20%. The application further provides a method for preparing a filter membrane by using the La MOF-20%-C adsorbent and an application of the La MOF-20%-C adsorbent as a phosphorus removal adsorbent. The application significantly reduces energy consumption and shortens time. The adsorbent has excellent phosphate adsorption capacity and sterilization effect.

The application provides a phosphate adsorbent and a preparation method and application thereof. The specific surface area of the clay-iron composite prepared by the application is 87.6 m 2 / g, which is higher than 63.6 m 2 / g of the clay. The adsorbent prepared by the application has a large specific surface area. The adsorption capacity of the clay-iron composite prepared by the application to the phosphate is 1.936 mg / g, and the adsorption rate is 88.165%. The bentonite selected by the application has a strong phosphate adsorption capacity and an expansion structure, which is beneficial to the loading of iron. After the iron is combined with the bentonite, the iron ion solution and the composite are separated, and then the iron oxide is synthesized again. Compared with the prior art of directly mixing the iron oxide and the clay mineral or synthesizing the iron oxide in the state that the clay mineral is dispersed in the iron ion solution, the method of the application retains the increased phosphate adsorption capacity of the iron oxide and reduces the content of iron in the composite, and has a higher environmental protection value.

The present invention discloses an emergency treatment method and system with nitrogen and phosphorus recovery. The method comprises the following steps: S1. The polluted water body passes through filtration and ozone treatment in sequence, which are respectively used to remove SS and COD in the water body; S2. The water body then passes through an ammonia nitrogen adsorbent and a phosphate adsorbent in sequence for purification, and under the ion exchange effect, NH4-N and phosphate in the water body are removed, and the treated water body is discharged; S3. A magnesium ion-containing solution is added to the regeneration liquid containing high-concentration NH4 + and PO4 3‑ formed after being treated by the ammonia nitrogen adsorbent and the phosphate adsorbent in step S2 to form magnesium ammonium phosphate precipitate, i.e., struvite, for nitrogen and phosphorus recovery. The beneficial technical effects of this solution are as follows: good pollutant removal effect, long adsorbent regeneration cycle. This method and system can effectively adsorb nitrogen and phosphorus in the water body, and can absorb and recycle the adsorbed nitrogen and phosphorus.

The invention relates to a preparation method of lanthanum carbonate tetrahydrate, which comprises the following steps: by taking an ammonium bicarbonate solution as a precipitator and a lanthanum salt solution as a raw material, adding the ammonium bicarbonate solution into the lanthanum salt solution (70-100 DEG C) in a forward precipitation manner, preparing amorphous lanthanum carbonate precursor precipitate after feeding is finished, and aging for 2-8 hours at the temperature of 10-59 DEG C to obtain the lanthanum carbonate tetrahydrate. Filtering, washing and drying the lanthanum carbonate tetrahydrate precipitate to obtain the lanthanum carbonate tetrahydrate compound. The method has the advantages of simple and controllable process, low preparation cost and high product purity, and is suitable for industrial production of pharmaceutical grade phosphate adsorbents.

The invention discloses a preparation method of a broad-spectrum pH-applicable high-performance phosphorus-removing lanthanum-based MOF composite adsorption material, a lanthanum-based adsorbent (HS) 2-La-MOF is prepared by taking MOFs as a matrix, and a sulfydryl group (-HS) is introduced into the material to form a stable La-S bond with central metal lanthanum (La), so that the structural stability of the material is effectively improved. Meanwhile, La and phosphate are promoted to further form a La-O-P inner-layer complex, and efficient removal of phosphate is achieved; furthermore, a nano confinement effect is provided by adding a GA material, and the lanthanum-based adsorbent composite material GA / (HS) 2-La-MOF is obtained. The two materials prepared by the invention can stably and efficiently remove phosphate in a water body in a wide pH range, the two materials still keep excellent phosphorus removal performance under an alkaline condition, the chemical stability is obviously superior to that of a conventional lanthanum-based MOF material, and the lanthanum-based MOF composite material is a phosphate adsorbent with a great practical application prospect.

An improved phosphate adsorbent based on mercapto click chemistry and its preparation method are disclosed. Modified chitosan and modified arginine, obtained by silane coupling agent modification, are used as raw materials. After obtaining arginine-functionalized chitosan particles through click chemistry, glutaraldehyde is used as a crosslinking agent and phosphate as a template. During the aerogel crosslinking process, combined with imprinting modification, the spatial structure of arginine is reorganized to prepare the aerogel adsorbent. This invention achieves the connection of functional monomers through click chemistry, followed by imprinting modification using phosphate as a template to obtain the aerogel adsorbent. It exhibits excellent selective phosphate adsorption in severely disturbed aquatic environments, and the phosphate adsorption capacity remains essentially unchanged after multiple cycles, promising large-scale and sustainable phosphorus removal from water bodies.

Preparation method and application of a multi-level confined adsorbent of graphene oxide modified MOF, which relates to a preparation method and application of an adsorbent material. The purpose of the present invention is to solve the problems that the existing metal-based MOF has low adsorption efficiency for phosphate and the treatment process is unstable and easy to lose, which is not convenient for subsequent recovery. Method: First, prepare mixed solution A; second, prepare mixed solution B; third, prepare solid powder C; fourth, carry out pyrolysis reaction to obtain a multi-level confined adsorbent of graphene oxide modified MOF. A multi-level confined adsorbent of graphene oxide modified MOF is used for adsorbing phosphate in wastewater. The multi-level confined adsorbent of graphene oxide modified MOF prepared by the present invention can reach an adsorption capacity of 250.2 mg·g ‑1 , and the adsorption kinetics is 13.092 mg·(g·min 0.5 ) ‑1 . The present invention can obtain a multi-level confined adsorbent of graphene oxide modified MOF.

This invention discloses a method for modifying biochar using ferric chloride and calcium chloride, and a method for enhancing phosphate adsorption. The preparation method includes the following steps: (1) mixing and impregnating the original biochar with a solution of ferric chloride and calcium chloride, and shaking the mixture thoroughly; (2) filtering the mixture to remove the supernatant, and drying the remaining solid material to obtain the modified biochar material; (3) placing the modified biochar material into a tube furnace, continuously introducing nitrogen gas into the tube furnace, and carbonizing at a high temperature of 600±5℃ for 2±0.1h. After the tube furnace cools to room temperature, the material is removed, cleaned, and dried to obtain biochar modified using ferric chloride and calcium chloride. The modification with ferric chloride and calcium chloride increases the adsorption active sites of the biochar, increases its specific surface area, makes its structure more porous, and enhances the adsorption effect.

The present invention belongs to the technical field of the preparation and use of environmental materials. Disclosed are a biomass-iron-based organic framework composite material, and a preparation method therefor and the use thereof. The method comprises: adding chitosan, an iron-based organic framework, i.e. MIL-88(B), and a cross-linking agent into an acetic acid solution, mixing same until uniform, then heating the mixture in a water bath, and adding same into a mixed solution dropwise for reaction, so as to obtain a biomass-iron-based organic framework composite material. The phosphate adsorption capacity of the biomass-iron-based organic framework composite material prepared in the present invention can reach 1.1 mmol / g, the adsorption capacity is higher than that of a pure iron-based organic framework material and a single biomass-based material, and the loss of the iron-based organic framework material is less than 1% when same is close to the optimal adsorption pH condition.

To provide a phosphate adsorbent exhibiting enhanced phosphate adsorption performance.SOLUTION: A phosphate adsorbent comprising CaO MgO 2SiO2 and at least one selected from the group consisting of MgO, CaO MgO SiO2, 2CaO MgO 2SiO2, 2MgO SiO2, and 2CaO SiO2.SELECTED DRAWING: Figure 1