CN111644148B - Preparation method of ultra-efficient sewage dephosphorization adsorbent - Google Patents

Preparation method of ultra-efficient sewage dephosphorization adsorbent Download PDF

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CN111644148B
CN111644148B CN202010522709.3A CN202010522709A CN111644148B CN 111644148 B CN111644148 B CN 111644148B CN 202010522709 A CN202010522709 A CN 202010522709A CN 111644148 B CN111644148 B CN 111644148B
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CN111644148A (en
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姚莹
王美玲
赵托
张艳
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Beijing Institute of Technology BIT
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    • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
    • B01J20/20—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising free carbon; comprising carbon obtained by carbonising processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
    • B01J20/04—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising compounds of alkali metals, alkaline earth metals or magnesium
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    • B01J20/3078—Thermal treatment, e.g. calcining or pyrolizing
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/288—Treatment of water, waste water, or sewage by sorption using composite sorbents, e.g. coated, impregnated, multi-layered
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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Abstract

The invention relates to a preparation method of an ultra-efficient sewage dephosphorization adsorbent, belonging to the technical field of sewage treatment and adsorbents. The method utilizes the combustion reaction of metal magnesium in the atmosphere of carbon dioxide, the simultaneous generation of MgO crystal and amorphous carbon is simply and rapidly realized in one step, and the MgO crystal and the amorphous carbon are uniformly combined in the nanoscale, the formed magnesium-based nano composite carbon material is the ultra-high-efficiency sewage phosphorus removal adsorbent, the adsorbent has extremely fast adsorption kinetics, a wide pH application range and strong impurity anion interference resistance, the adsorption capacity on phosphorus in a solution is higher than 1000mg/g, and the effect of efficiently and rapidly removing phosphorus in actual sewage with various complex components can be realized. The method disclosed by the invention is simple to operate, short in preparation period, rich and cheap in raw material source, and the adsorbent has no toxicity to the environment, does not cause secondary pollution in preparation and dephosphorization application of the adsorbent, and has a good application prospect.

Description

Preparation method of ultra-efficient sewage dephosphorization adsorbent
Technical Field
The invention relates to a preparation method of an ultra-efficient sewage dephosphorization adsorbent, belonging to the technical field of sewage treatment and adsorbents.
Background
With the increasing development and utilization of environmental resources by human beings, the continuous development of urbanization and industrialization and the heavy use of agricultural fertilizers and phosphorus-containing detergents, nitrogen and phosphorus nutrients entering water bodies such as lakes, reservoirs, rivers and the like are continuously increased, algae are greatly propagated, and large-area water eutrophication is caused. The eutrophication of the water body not only seriously damages the ecological environment of the water body, reduces the use function of the water body and accelerates the death of the water body, but also influences shipping and hinders economic development. At present, the eutrophication problem in water bodies such as rivers, lakes and the like in China is becoming more severe, so that the treatment of sewage containing nitrogen and phosphorus becomes an important problem to be solved urgently. Although nitrogen and phosphorus are the main factors responsible for eutrophication, aquatic organisms such as algae are more sensitive to phosphorus elements. When the concentration of the phosphorus in the water body is only above 0.02mg/L, the eutrophication of the water body can be obviously promoted. Therefore, there is an urgent need to develop a simple and efficient method and technique for preventing eutrophication of water bodies by removing phosphorus in the water bodies in situ or before discharging sewage into the water bodies.
At present, there are three main technologies for treating phosphorus-containing wastewater at home and abroad, namely a chemical precipitation method using aluminum salt and iron salt as flocculants, a biological treatment method, and a physical method including ion exchange, reverse osmosis, adsorption and the like. Wherein, the operation conditions of the chemical precipitation method and the biological treatment are strict, the subsequent treatment of the generated sludge is difficult, and new pollutants are introduced into the water body by the chemical method; the ion exchange method and the reverse osmosis method are only suitable for the conditions of low phosphorus concentration and single pollutant and are expensive; adsorption methods have received much attention and research because of their advantages of being simpler and more efficient, low cost, flexible to operate, reusable, and the like. However, the reported adsorbents have low phosphorus removal capability and cannot meet the actual requirements for treating phosphorus-containing sewage, such as red mud, activated carbon, coconut shells, fly ash, dolomite, slag, aluminum oxides, iron oxide tailings and the like. The preparation of the adsorbent with higher efficiency and high phosphorus adsorption capacity is the bottleneck of the current adsorption method research.
Yao et al directly synthesized a tomato plant waste rich in Mg (OH) by high temperature pyrolysis using the tomato plant waste rich in Mg as raw material2And MgO nanoparticles), the carbon particles having a particle size in the range of 0.5mm to 1mm, and an adsorption capacity for phosphorus in an aqueous solutionHigher than 100Mg/g (Engineered carbon (biochar) prepared by direct gasification of Mg-cultured substrate tissues: chromatography and phosphate removal potential. Bioresource Technol 2013,138, 8-13.). On the basis of the research, carbon of waste lithium ion batteries is used as a raw material, the particle size of the carbon is 10-20 mu m, and nano-level Mg (OH) is loaded on the surface of a carbon matrix through magnesium solution pretreatment and high-temperature pyrolysis2And MgO particles, which have strong removal capacity to phosphorus in the solution, and the adsorption capacity can reach more than 500mg/g (Mesorbon Microbead Carbon-Supported Magnesium Hydroxide Nanoparticles: Turning speed Li-ion Battery Anode. high efficiency phosphorus Adsorbent for Water treatment. ACS applied Mater interface 2016,8, 21315. 21325.). This superior phosphorus adsorption capacity is mainly attributed to the nanoscale MgO and Mg (OH) on the surface of the carbon substrate2Particles capable of chemically reacting with phosphate groups on carbon surfaces to form precipitates (e.g., MgHPO)4And Mg3(PO4)2) The removal of phosphorus in the sewage is realized. However, the reported Mg-carbon composite nano-materials combine Mg and carbon by a high-temperature pyrolysis method, and MgO/Mg (OH) with adsorption activity is loaded on the surface of carbon particles with micron-sized or millimeter-sized particle diameter2And (3) granules. The larger particle size carbon matrix not only results in lower Mg loading (molar ratio < 20%), but also reduces the effective contact area of MgO with the solution, thereby limiting further increases in the amount of phosphorus adsorbed in the wastewater by the Mg-carbon composite. Therefore, the research on a preparation method which is cheap, simple to operate and quick, and the prepared magnesium-based nano composite carbon material with high Mg content and high-activity reaction interface has great significance for treating phosphorus-containing sewage.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a preparation method of an ultra-high-efficiency sewage phosphorus removal adsorbent, which utilizes the combustion reaction of metal magnesium in the atmosphere of carbon dioxide to simply and rapidly realize the simultaneous generation of MgO crystals and carbon in one step, the MgO crystals and the carbon are uniformly combined in a nanometer scale, the MgO crystals and the carbon have extremely high theoretical MgO content (the molar ratio is 60 percent), and the adsorbent has ultra-high phosphorus removal capacity (the phosphorus adsorption capacity is more than 1000mg/g) to phosphorus in a solution.
The purpose of the invention is realized by the following technical scheme.
A preparation method of an ultra-efficient sewage dephosphorization adsorbent comprises the following steps: metal magnesium in CO2And (3) burning at 600-800 ℃ in a protective gas atmosphere, collecting a solid product after the metal magnesium is completely burnt, washing the solid product with water with the purity not less than that of deionized water, and drying to obtain the ultra-efficient sewage dephosphorization adsorbent.
Further, the magnesium metal is in the shape of a block, a strip or powder.
Further, CO2The gas flow of the shielding gas is 50cm3/min～150cm3/min。
Further, heating to 600-800 ℃ at a heating rate of 5-10 ℃/min.
When the ultra-efficient sewage phosphorus removal adsorbent prepared by the method is used for removing phosphorus in a phosphorus-containing solution, the pH value of the phosphorus-containing solution is preferably 1-11, the adsorption time is not less than 6 hours, the adsorption capacity of the adsorbent can reach more than 80% of the equilibrium adsorption capacity, and the mass ratio of the adsorbent to the phosphorus in the phosphorus-containing solution is not less than 1.
Has the advantages that:
(1) the invention provides a preparation method of a novel Mg-carbon nano composite material by a non-traditional pyrolysis method, namely, CO is subjected to CO2And burning the magnesium metal in the atmosphere to prepare the composite carbon material with extremely high nano MgO content. During the combustion process, MgO crystals and amorphous carbon are generated simultaneously, so that the nano-scale MgO flaky particles are tightly embedded in the carbon layer with a structure with more defects. The carbon layer not only supports and maintains the nano-scale structure of the MgO particles, but also the defect structure of the carbon layer can serve as an active adsorption site of phosphorus. The structure of the fusion contact of the amorphous carbon and the MgO particles in the nano-scale depth realizes the extremely high MgO content, meanwhile, the extremely small nano-sheet-shaped MgO particles (10 nm-20 nm) have larger effective adsorption area, and the removal capability of phosphorus in the solution is enhanced through the synergistic effect of the carbon matrix and the nano-MgO particles.
(2) In the method, the calcination temperature is strictly controlled, and an excessively high calcination temperature can improve the crystallinity of carbon to reduce a defect structure with adsorption activity and possibly cause the agglomeration of MgO nano flaky particles into a large blocky structure; especially above 1000C, carbon and carbon dioxide undergo side reactions to form carbon monoxide, which will deplete the carbon material and destroy the nanostructure of the Mg-C composite.
(3) The calcined product is cleaned in the method, so that water-soluble impurities possibly contained in the material are removed, and secondary pollution to a water body when the calcined product is used as a sewage adsorbent is prevented.
(4) The adsorbent prepared by the method has extremely fast adsorption kinetics, can quickly reach the phosphorus removal rate of more than 99 percent, has the adsorption capacity of more than 1000mg/g for phosphorus in a solution, and has wide pH application range and stronger impurity anion interference resistance, so the adsorbent can realize the effect of efficiently and quickly removing phosphorus in actual sewage with various complex components.
(5) The method disclosed by the invention is simple to operate, short in preparation period, rich and cheap in raw material source, and the adsorbent has no toxicity to the environment, does not cause secondary pollution in preparation and dephosphorization application of the adsorbent, and has a good application prospect.
Drawings
Fig. 1 is an XRD (X-ray diffraction) pattern of the adsorbent prepared in example 1.
Fig. 2 is an SEM (scanning electron microscope) image of the adsorbent prepared in example 1.
Fig. 3 is a high power SEM image of the magnesium-based nanocomposite carbon material prepared in example 1.
Fig. 4 is an EDS (energy spectrum analysis) diagram corresponding to fig. 3.
Fig. 5 is an XPS (X-ray photoelectron spectroscopy) full spectrum of the adsorbent prepared in example 1.
FIG. 6 is an XPS plot of Mg 2p in the adsorbent prepared in example 1.
Fig. 7 is a low power TEM (transmission electron microscope) image of the adsorbent prepared in example 1.
Fig. 8 is a SAED (selected area electron diffraction) diagram corresponding to fig. 7.
Fig. 9 is a high power TEM image of the adsorbent prepared in example 1.
Fig. 10 is an enlarged TEM image of the box area of fig. 9.
FIG. 11 is a graph of the high angle annular dark field image of FIG. 7 with Mg, O and C element distributions in corresponding locations.
FIG. 12 is a graph showing the adsorption kinetics of phosphorus by the adsorbent prepared in example 1.
Fig. 13 is a graph of the diffusion of phosphorus within the sorbent particles prepared in example 1.
FIG. 14 is a plot of the adsorption isotherm for phosphorus for the adsorbent prepared in example 1.
FIG. 15 is a graph showing the comparison of the amounts of phosphorus adsorbed by the adsorbents prepared in example 1 in solutions of different pH values.
FIG. 16 is a graph showing a comparison of the amounts of phosphorus adsorbed by the adsorbents prepared in example 1 in the presence of different coexisting anions.
Detailed Description
The invention is further illustrated by the following figures and detailed description, wherein the process is conventional unless otherwise specified, and the starting materials are commercially available from a public disclosure without further specification.
Example 1
Adding 5g of magnesium strip into Al2O3Placing the ark in a tube furnace, and introducing gas into the furnace at a flow rate of 70cm3CO/min2And heating the gas to 680 ℃ at the heating rate of 10 ℃/min to burn the magnesium strips, completely burning the magnesium strips after 1h, naturally cooling to room temperature, collecting the solid product, washing the solid product with deionized water, and drying the solid product in an oven at 80 ℃ to obtain the ultra-high efficiency sewage dephosphorization adsorbent.
In the XRD pattern of FIG. 1, diffraction peaks at 37.10 °, 43.08 °, 62.46 °, 74.86 ° and 78.78 ° correspond to (111), (200), (220), (311) and (222) crystal planes of a hexagonal structure of MgO (JCPDS 89-4248), respectively; there is a diffraction peak with very low intensity near 26 deg., corresponding to the (002) crystal plane of C. This result indicates that an adsorbent containing MgO crystals and amorphous carbon was successfully prepared (the prepared adsorbent may also be referred to as a magnesium-based nanocomposite carbon material).
As can be seen from the SEM images of fig. 2 and 3 at different magnifications, the prepared adsorbent consisted of irregular cubic particles, and the SEM images at high magnifications further revealed that the cubic particles were formed by stacking a large number of irregularly shaped microparticles having smooth surfaces. From the EDS spectrum of fig. 3, it can be seen that the EDS spectrum peaks for Mg and O in the microparticles are high, with an atomic ratio of Mg to O of 1:1.16, approximately in accordance with the stoichiometry of MgO.
The XPS spectrum of fig. 5 shows that three strong peaks of Mg photoelectrons are clearly detected from the prepared adsorbent; the two peaks shown in the XPS spectrum of Mg 2p in FIG. 6, located at 50.8eV and 49.2eV, can be assigned to MgO and Mg, respectively.
As can be seen from FIGS. 7 and 11, irregular micrometer particles are observed in FIGS. 2 and 3, which are stacked by innumerable lamellar structures having a particle size of 10nm to 20 nm. The clear multiple concentric diffraction pattern presented in fig. 8 shows that the prepared adsorbent consists of a polycrystalline structure, which is consistent with the previous XRD results, i.e. the prepared adsorbent comprises MgO crystals and amorphous carbon. It is clearly observed from the high resolution image of fig. 9 that flat MgO nanoparticles with a particle size of 10nm are tightly bound to the more disordered carbon layer. The higher magnification TEM data in fig. 10 again demonstrate that the ordered lattice layer of the outer layer is MgO crystal particles. The elemental distribution plot of fig. 11 shows that the Mg, O and C elements are uniformly mixed at the nanoscale. From this, it is understood that MgO and C are uniformly mixed in the nano-scale because they are simultaneously formed and precipitated during the preparation. The existence of the amorphous carbon layer supports and maintains the ultra-small nano particles (10 nm-20 nm) of MgO particles, so that the material has a very large adsorption reaction interface, and the exposed carbon layer rich in defect structures can also be used as an active site for adsorbing phosphorus, and the synergistic effect of MgO and carbon can greatly improve the phosphorus removal capability of the material.
The prepared adsorbent is used for carrying out adsorption test on a phosphorus solution: KH was used for adsorption experiments2PO4And deionized water to prepare a phosphorus stock solution, and storing at room temperature. Is made ofThe dosage of the prepared adsorbent is 0.05g, the volume of the phosphorus solution is 25mL, and the volume of a centrifugal tube for adsorption reaction is 50 mL. The adsorption reaction was carried out at room temperature (25. + -. 3 ℃ C.) on a mechanical shaker at 200 rpm. All adsorption contact times were 24h except for the adsorption kinetics experiments. Except for the adsorption isotherm experiments, all initial concentrations of phosphorus were 50 mg/L. After the adsorption reaction, the supernatant was filtered through a 0.22 μm filter and the phosphorus concentration of the filtrate was measured by the ascorbic acid method (ESS method 310.132). The phosphorus adsorption amount is calculated according to the change of phosphorus concentration before and after adsorption, each experiment is carried out in parallel, and when the experiment error is less than 3%, the average value is taken as effective data.
The adsorption isotherm experiment adopts a gradient concentration phosphorus solution with the concentration of 20 mg/L-1000 mg/L. According to adsorption kinetics experiments, the adsorption contact time intervals are 20min, 40min, 1h, 2h, 4h, 6h, 12h and 24 h. And (3) adjusting the pH value of the phosphorus solution to be a gradient value between 1 and 12 by using HCl or NaOH solution with negligible volume. The influence of the coexisting anion on the adsorption performance was determined by using the coexisting anion (chloride, nitrate, sulfate or carbonate) at a concentration of 0.1M.
Adsorption kinetics experiments were used to explore the change in phosphorus adsorption capacity of the prepared adsorbent as adsorption contact time increased. As can be seen from fig. 12, the prepared adsorbent can rapidly adsorb phosphorus, and the adsorption equilibrium is reached in a short time. After 6 hours, the phosphorus adsorption reached an equilibrium capacity of 83%; in 12 hours, the phosphorus adsorption amount exceeds 99 percent of the equilibrium adsorption amount, and the adsorption reaches the equilibrium. The process that the adsorption rate is changed from fast to slow is that the initial adsorption rate is very high because the number of active adsorption sites of the metal oxide with positive charges is large and the concentration of phosphorus in the solution is high at the beginning; in the later stage of adsorption, as the concentration of phosphorus in the solution is reduced (the removal rate is close to 100%), and the number of available active sites is gradually reduced, the adsorption rate is gradually reduced.
Experimental data of adsorption kinetics were fitted using the pseudo first order, pseudo second order, ritchae N order, Elovich and intraparticle diffusion models represented by equations (1), (2), (3), (4) and (5), respectively, for analysis of the adsorption mechanism.
ln(qe-qt)＝lnqe-k1t (1) pseudo first order
Figure GDA0002607464640000061
Figure GDA0002607464640000062
Figure GDA0002607464640000063
qt＝kit1/2+Ci(5) Diffusion in particles
Here, q ist(mg·g-1) And q ise(mg·g-1) Is the amount of phosphorus adsorbed at time t and at the equilibrium moment; k is a radical of1(h-1)、k2(g·(mg·h)-1)、kn(gn-1·(mgn-1·h)-1) Is the adsorption rate constant; α (mg (g. h)-1) Initial adsorption rate; beta (g. mg)-1) Is the desorption constant; k is a radical ofi(mg g-1·h-1/2) Is the diffusion rate constant within the membrane; ci(mg·g-1) Is a constant in the intra-granular diffusion equation.
The results of the fitting calculations on the adsorption kinetics data are detailed in table 1. Regression coefficient (R)2) The larger the size, the higher the degree of composition of the corresponding model and the adsorption data. The possible adsorption mechanism of the adsorbent can be estimated from the most suitable adsorption model. From the data in the table, it can be seen that R2The best fitting of the N-order adsorption model and the adsorption data is analyzed according to the numerical value of the N-order adsorption model; from qeCompared with the value, the calculation result of the pseudo second-order model is closest to the actual adsorption quantity, namely, the fitting degree is better. The pseudo second-order adsorption model assumes that the main adsorption process is a chemical reaction process, and the N-order adsorption model represents that the adsorption process relates to various adsorption mechanisms. This is consistent with the conclusion from characterization experiments that MgO nanoparticles are precipitated by chemical precipitationThe precipitation reaction adsorbs phosphorus element, and the defect structure on the carbon surface also serves as an active site to adsorb phosphorus. The curve fitted to the adsorption kinetics data using the intra-particle diffusion model is shown in FIG. 13, where the correlation between the fitted curve and the adsorption data is extremely high R20.9902, this indicates that the controlled process of phosphorus adsorption on mg-based nanocomposite carbon materials is a diffusion step between particles of the material and in the pores inside the particles. Namely, the high-adsorption interface adsorbent consisting of the nano-sheets can improve the diffusion rate, thereby effectively improving the adsorption rate.
As can be seen from fig. 14, the phosphorus adsorption amount sharply increases and gradually reaches an equilibrium as the initial phosphorus concentration increases. Adsorption isotherm data were fitted using Langmuir, Freundlich, Langmuir-Freundlich, Redlich-Peterson and Temkin models represented by equations (6), (7), (8), (9) and (10), respectively, for analysis of adsorption mechanism.
Figure GDA0002607464640000071
Figure GDA0002607464640000072
Figure GDA0002607464640000073
Figure GDA0002607464640000074
Figure GDA0002607464640000075
Here, K (L. mg)-1)，Kf((mg1-n Ln·)g-1)，Kif(Ln·mg-n) And Kr(L·g-1) Coefficients representing the first four models; q (mg. g)-1) Represents the maximum capacity; ce(mg·L-1) Indicates the sorbate concentration at equilibrium; n (dimensionless), a (L)n·mg-n)，b((J·g)·mg-1) And A (L. mg)-1) Are constants for the isothermal models of Freundlich, Redlich-Peterson, and Temkin, respectively.
The results of fitting calculations on the adsorption isotherm data are detailed in table 1. As can be seen from the data in the table, the adsorption model with the best fitting degree is the Langmuir-Freundlich model. R of three models, Langmuir-Freundlich and Redlich-Peterson2The values are 0.9922, 0.9940, and 0.9923, respectively, which are better fits than the Freundlich and Temkin models. This result suggests that the adsorption of phosphorus onto the mg-based nanocomposite carbon material may occur on a non-uniform surface, involving multiple adsorption mechanisms. This conclusion again demonstrates that MgO nanoparticles and defect-structure-rich carbon have a synergistic effect when Mg-based nanocomposite carbon material adsorbs phosphorus. The maximum adsorption capacity of the Mg-based nanocomposite carbon material for phosphorus estimated using the Langmuir model was 1135.0mg g-1The phosphorus adsorption capacity is far higher than that of other adsorbents reported at present.
TABLE 1
Figure GDA0002607464640000076
Figure GDA0002607464640000081
The pH value influences the ion species in the phosphorus solution and the surface properties of the adsorbent, and coexisting anions generally compete with phosphorus for adsorption on adsorption sites, which may reduce the actual phosphorus removal rate of the adsorbent. As can be seen from FIG. 15, the pH value of the magnesium-based nanocomposite carbon material has little influence on the phosphorus adsorption capacity within the range of 1-11, which indicates that the pH value range of the magnesium-based nanocomposite carbon material for effective phosphorus removal is extremely wide; when the pH value exceeds 12, the phosphorus removal capability is obviously reduced. This broader pH window is due to the zero charge point value (pH) of magnesium oxideZPC) Very high when the pH of the solution is higher than PZCMgOIn this case, the electrostatic repulsive force between the negatively charged MgO surface and the phosphorus ions is increased, resulting in a lower degree of phosphorus adsorption. As can be seen from FIG. 16, Cl-Or NO3 -The existence of (A) has no influence on the phosphorus adsorption amount of the Mg-based nano composite carbon material, and the phosphorus adsorption amount of the Mg-based nano composite carbon material is in SO4 2-Or CO3 2-The presence of (b) results in only a small reduction in the amount of adsorption, probably due to the higher ionic strength of the dianion. Under the conditions of a wider pH value range and competitive adsorption of various coexisting anions, the prepared magnesium-based nano composite carbon material shows ultrahigh phosphorus removal rate, which indicates that the material can meet the application requirements of actual sewage treatment of various complex components.
The characterization test results prove that the non-traditional pyrolysis preparation process successfully prepares the novel magnesium-based nano composite carbon material (or the ultra-efficient sewage dephosphorization adsorbent), and the microstructure of the novel magnesium-based nano composite carbon material is formed by tightly embedding nano sheets with the particle size of 10-20 nm in an amorphous carbon layer. The adsorbent with high Mg content, extremely large adsorption reaction interface and multiple adsorption active sites shows excellent adsorption performance when used as a sewage dephosphorization adsorbent.
In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (7)

1. The application of the ultra-high efficiency phosphorus removal adsorbent for sewage is characterized in that: the adsorbent is prepared by adopting the following method,
metal magnesium in CO2In a protective gas atmosphere at 600 deg.CoC~800 oAnd C, burning, collecting a solid product after the metal magnesium is completely burnt, washing the solid product with water with the purity not less than that of deionized water, and drying to obtain the ultra-high efficiency sewage dephosphorization adsorbent.
2. The application of the ultra-high efficiency sewage dephosphorization adsorbent according to claim 1, wherein: the magnesium metal is in the shape of block, strip or powder.
3. The application of the ultra-high efficiency sewage dephosphorization adsorbent according to claim 1, wherein: CO 22The gas flow of the shielding gas is 50cm3/min~150 cm3/min。
4. The application of the ultra-high efficiency sewage dephosphorization adsorbent according to claim 1, wherein: by 5oC/min~10 oHeating to 600 ℃ at a temperature rise rate of C/minoC~800 oC。
5. The application of the ultra-high efficiency sewage dephosphorization adsorbent according to any one of the claims 1 to 4, wherein: when the adsorbent is used for removing phosphorus in the phosphorus-containing solution, the pH value of the phosphorus-containing solution is 1-11.
6. The application of the ultra-high efficiency sewage dephosphorization adsorbent according to claim 5, wherein: when the adsorbent is used for removing phosphorus in a phosphorus-containing solution, the adsorption time is not less than 6 hours, and the adsorption capacity of the adsorbent reaches more than 80% of the equilibrium adsorption capacity.
7. The application of the ultra-high efficiency sewage dephosphorization adsorbent according to claim 5, wherein: when the adsorbent is used for removing phosphorus in the phosphorus-containing solution, the mass ratio of the adsorbent to the phosphorus in the phosphorus-containing solution is not less than 1.
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CN116037631A (en) * 2022-12-29 2023-05-02 贵州鼎瑞环保科技有限公司 Phosphogypsum raw slag harmless treatment method

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102247804A (en) * 2011-05-20 2011-11-23 上海大学 Preparation method of active carbon fiber phosphorous removing agent carrying lanthanum hydroxide
CN102441365A (en) * 2011-05-19 2012-05-09 北京师范大学 Preparation method of phosphorus adsorption composite material and phosphorus adsorption composite material
CN103723831A (en) * 2012-10-11 2014-04-16 中国科学院生态环境研究中心 Application of forsterite as phosphorus-removing substrate material
CN103801258A (en) * 2014-03-12 2014-05-21 福州大学 Nickel slag adsorption material applicable to treatment of phosphorus-containing wastewater and preparation method thereof
WO2014144214A3 (en) * 2013-03-15 2014-11-27 Ndsu Research Foundation Iron-functionalized alginate for phosphate and other contaminant removal and recovery from aqueous solutions
CN104291482A (en) * 2014-09-18 2015-01-21 中国海洋石油总公司 Treatment method for wastewater containing high-concentration phosphite
CN107583636A (en) * 2017-10-17 2018-01-16 天津普瑞特净化技术有限公司 A kind of activated carbon desulphurization agent of supported magnesium oxide and preparation method thereof
CN111203173A (en) * 2020-01-16 2020-05-29 陈赫然 Phosphorus removal material based on collophanite tailings and preparation and application methods thereof

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102441365A (en) * 2011-05-19 2012-05-09 北京师范大学 Preparation method of phosphorus adsorption composite material and phosphorus adsorption composite material
CN102247804A (en) * 2011-05-20 2011-11-23 上海大学 Preparation method of active carbon fiber phosphorous removing agent carrying lanthanum hydroxide
CN103723831A (en) * 2012-10-11 2014-04-16 中国科学院生态环境研究中心 Application of forsterite as phosphorus-removing substrate material
WO2014144214A3 (en) * 2013-03-15 2014-11-27 Ndsu Research Foundation Iron-functionalized alginate for phosphate and other contaminant removal and recovery from aqueous solutions
CN103801258A (en) * 2014-03-12 2014-05-21 福州大学 Nickel slag adsorption material applicable to treatment of phosphorus-containing wastewater and preparation method thereof
CN104291482A (en) * 2014-09-18 2015-01-21 中国海洋石油总公司 Treatment method for wastewater containing high-concentration phosphite
CN107583636A (en) * 2017-10-17 2018-01-16 天津普瑞特净化技术有限公司 A kind of activated carbon desulphurization agent of supported magnesium oxide and preparation method thereof
CN111203173A (en) * 2020-01-16 2020-05-29 陈赫然 Phosphorus removal material based on collophanite tailings and preparation and application methods thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Synthesis of porous MgO-biochar nanocomposites for removal of phosphate and nitrate from aqueous solutions;Ming Zhang et al.;《Chemical Engineering Journal》;20120825;第210卷;摘要，第27页2.2 MgO-生物炭纳米复合材料、2.4吸附磷酸盐和硝酸盐，第31页4结论 *
镁颗粒在CO2中的点火燃烧特性试验;冯运超等;《固体火箭技术》;20151231;第38卷(第5期);摘要、第735页1.2试验过程、第736页2.3环境压强对点火燃烧特性的影响、第737页2.4燃烧产物特性分析、第738页3结论 *

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