Preparation method and application of alumina-loaded copper-doped graphene-like catalyst

Abstract

The invention relates to the field of catalysts, in particular to a preparation method and application of an alumina-loaded copper-doped graphene-like catalyst, and the preparation method comprises the following steps: step 1, dispersing biomass in deionized water to form a suspension A; step 2, adding an aluminum salt and an iron salt into the turbid liquid A to form a turbid liquid B; step 3, adding a nitrogen source into the turbid liquid B to form impregnation liquid C; step 4, pouring the steeping liquor C into a beaker filled with alumina pellets, and drying to obtain dried pellets; and 5, roasting the dried pellets in a tubular furnace, cooling to room temperature, repeatedly washing with water, and drying to obtain the catalyst. The catalyst disclosed by the invention can be used for rapidly degrading refractory organic pollutants in water within 30 minutes under the synergism of microorganisms. The catalyst provided by the invention has good stability in the process of removing organic pollutants, and almost no metal ions are released.

Description

Technical Field

[0001] The present invention relates to the field of catalysts, and particularly to a preparation method and application of an alumina-supported copper-doped graphene-like catalyst. Background Art

[0002] China is a country with extremely scarce water resources, and the per capita water resources are less than 1 / 4 of the world average. In recent decades, with the accelerated development of urban construction in China, the problem of water pollution has become increasingly prominent, the contradiction of water resources has become increasingly acute, and it has begun to affect the sustainable development process of various fields. The increasingly severe water pollution phenomenon is bound to have a serious negative impact on social and economic development and the healthy survival of humans. Therefore, it is imperative to protect the water environment and purify polluted water quality. Among the various and complex water pollution sources, toxic and harmful refractory organic compounds pose a potential danger to water bodies, aquatic ecosystems, and humans. These refractory pollutants mainly include aromatic compounds such as drugs, skin care products, pesticides, and endocrine disruptors. Moreover, these pollutants all contain aromatic rings, have stable structures, are difficult to degrade in the natural environment, can thus exist in water bodies for a long time, accumulate gradually through the food chain, and finally affect human health. Therefore, developing effective technologies and methods is the most important issue at present. Summary of the Invention

[0003] Aiming at the problems existing in the prior art, the purpose of the present invention is to provide a preparation method and application of an alumina-supported copper-doped graphene-like catalyst.

[0004] The purpose of the present invention is achieved by the following technical solutions:

[0005] In the first aspect, the present invention provides a preparation method of an alumina-supported copper-doped graphene-like catalyst, including the following steps:

[0006] Step 1, disperse biomass in a certain volume of deionized water to form suspension A;

[0007] Step 2, add aluminum salt and iron salt to suspension A, stir evenly and adjust the pH of the solution to form suspension B;

[0008] Step 3, add a nitrogen source to suspension B, and after complete dissolution, form impregnation solution C;

[0009] Step 4, pour impregnation solution C into a beaker containing alumina balls, let it stand for a certain time, and then dry to obtain dry balls;

[0010] Step 5, calcine the dry balls in a tubular furnace, cool to room temperature, wash them repeatedly with water, and dry to obtain the immobilized FeAl-NC-Al2O3 water purification catalyst.

[0011] Preferably, in the step 1, the biomass is one of silkworm excrement, corncob, garlic straw, cyclodextrin, and chitosan.

[0012] Preferably, in the step 1, the mass-volume ratio of cyclodextrin to deionized water is (1 - 100) g: 1 L.

[0013] More preferably, in the step 1, the biomass is cyclodextrin, and the mass-volume ratio of cyclodextrin to deionized water is 57 g: 1 L.

[0014] Preferably, in the step 1, the stirring time is 30 min.

[0015] Preferably, in the step 2, the iron salt is one of ferric chloride, ferric nitrate, ferric sulfate, and ferric acetate.

[0016] Preferably, in the step 2, the aluminum salt is one of aluminum chloride, aluminum nitrate, and aluminum sulfate.

[0017] Preferably, in the step 2, the iron ions in suspension A are 0 - 200 mmol, and the molar ratio of iron to aluminum is 1:1 - 5.

[0018] Preferably, in the step 3, the nitrogen source is one of urea, dicyandiamide, melamine, and triethylenetetramine.

[0019] Preferably, in the step 3, the mass-volume ratio of the nitrogen source to suspension B is (1 - 300) g: 1 L.

[0020] Preferably, in the step 4, the mass-volume ratio of the alumina spheres to impregnation solution C is (300 - 900) g: 1 L.

[0021] Preferably, in the step 4, the static temperature is 80 °C, the static time is 1 - 24 h, and the drying temperature is 80 °C.

[0022] Preferably, in the step 5, the heating rate of the tubular furnace is 5 °C / min, an inert gas is used as the protective gas, the temperature is maintained at 500 - 900 °C, and the residence time is 2 - 5 hours.

[0023] In a second aspect, the present invention provides an alumina-supported copper-doped graphene catalyst prepared by the above preparation method.

[0024] In a third aspect, the present invention provides an application of the alumina-supported copper-doped graphene catalyst in degrading organic pollutants in water.

[0025] Preferably, the organic pollutants include at least one of tetracycline (TC), bisphenol A (BPA), and ciprofloxacin (CIP).

[0026] Fourthly, the present invention provides an application device for an alumina-supported copper-doped graphene catalyst, comprising a solidification bed, a peristaltic pump and a plurality of liquid inlet pipes; the bottom of the solidification bed is provided with a water inlet, and the upper end is provided with a water outlet and a packing port; the pollutant liquid inlet pipe passes through the peristaltic pump and enters the solidification bed to react with the catalyst, and the solution flows out from the outlet water after the pollutants are degraded and treated, thus completing the treatment.

[0027] The beneficial effects of the present invention are as follows:

[0028] 1. The catalyst of the present invention can rapidly degrade refractory organic pollutants in water within 30 min in cooperation with microorganisms.

[0029] 2. The catalyst of the present invention has good stability during the process of removing organic pollutants, and hardly releases metal ions.

[0030] 3. The catalyst of the present invention belongs to a solid-supported industrial application catalyst, which is convenient for separation from water and recycling.

[0031] 4. The raw materials of the catalyst of the present invention are cheap, with low cost, convenient synthesis and simple process. Description of the Drawings

[0032] The present invention is further illustrated by the accompanying drawings, but the embodiments in the drawings do not constitute any limitation to the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the following drawings without creative work.

[0033] Figure 1 It is a physical photograph of the catalyst prepared in the example.

[0034] Figure 2 It is a schematic structural diagram of a solidification bed reactor; wherein, 1 - pollutant liquid inlet pipe, 2 - peristaltic pump, 3 - solidification bed, 4 - water outlet, 5 - catalyst.

[0035] Figure 3 It is a curve graph of the degradation effect of the catalyst on CIP.

[0036] Figure 4 It is a curve graph of the degradation effect of the catalyst on TC.

[0037] Figure 5 It is a curve graph of the degradation effect of the catalyst on BPA. Detailed Embodiments

[0038] The technical solution of the present invention will be described below through specific specific examples. It should be understood that one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combined steps or the insertion of other method steps between these clearly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. Moreover, unless otherwise specified, the numbers of the method steps are only convenient tools for identifying the method steps, rather than limiting the arrangement order of the method steps or the scope in which the present invention can be implemented. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope in which the present invention can be implemented.

[0039] In order to better understand the above technical solution, the exemplary embodiments of the present invention will be described in more detail below. Although the exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0040] The present invention will be further described below in conjunction with the following embodiments.

[0041] Example 1

[0042] A preparation method of an alumina-supported copper-doped graphene-like catalyst includes the following steps:

[0043] Step 1: Disperse 50 g of cyclodextrin in 1 L of deionized water and stir for 30 min to form suspension A;

[0044] Step 2: Add aluminum chloride and ferric chloride to suspension A. The amount of ferric ions is 100 mmol, and the molar ratio of iron to aluminum is 1:4. Stir evenly and adjust the pH of the solution to 8 to form suspension B;

[0045] Step 3: Add 120 g of urea to suspension B. After complete dissolution, impregnation solution C is formed;

[0046] Step 4: Pour impregnation solution C into a beaker containing 700 g of alumina spheres. Let it stand at 80 °C for 12 h, and then dry at 80 °C to obtain dried spheres;

[0047] Step 5: Place the dried spheres in a tube furnace for calcination. The heating rate of the tube furnace is 5 °C / min, an inert gas is used as the protective gas, the temperature is maintained at 800 °C, and the residence time is 3 hours. Then cool to room temperature and wash repeatedly with water. After drying, it is the immobilized FeAl-NC-Al2O3 water purification catalyst.

[0048] Application Example 1

[0049] Application of a FeAl-NC-Al2O3 water purification catalyst as a fixed-bed filler in Example 1 of the present invention in degrading organic pollutants in water, the method comprising the following steps:

[0050] As Figure 2 shown, a fixed-bed reactor was set up to treat organic pollutants in water. The operating conditions of the solidification bed reactor are as follows: The organic pollutants are transported to the solidification bed 3 through a peristaltic pump 2. The flow rate of the organic pollutant (BPA) is 1.8 mL / min, the residence time is 30 min, and the solution is neutral. As can be seen from Figure 3 it, in the first 46 days of operation, the removal rate of CIP reached 100%. However, as the operation time elapsed, the removal rate of CIP slowly decreased and gradually stabilized, and finally the removal rate remained above 54.2%. This may be due to the adsorption of CIP by the catalyst in the early stage. After operating for a period of time, microorganisms were enriched on the surface of the catalyst in the reactor and gradually adapted to CIP. At this time, the microorganisms began to play a role.

[0051] Application Example 2

[0052] Application of a FeAl-NC-Al2O3 water purification catalyst as a fixed-bed filler in Example 1 of the present invention in degrading organic pollutants in water, the method comprising the following steps:

[0053] As Figure 2 shown, a fixed-bed reactor was set up to treat organic pollutants in water. The operating conditions of the solidification bed reactor are as follows: The organic pollutants are transported to the solidification bed 3 through a peristaltic pump 2. The flow rate of the organic pollutant (TC) is 1.8 mL / min, the residence time is 30 min, and the solution is neutral. As can be seen from Figure 4 it, during the operation period of up to 106 days, the FeAl-NC-Al2O3 biofiltration reactor showed continuous and efficient degradation ability for TC, and its removal rate was always maintained at 100%. Combining the results of removing CIP before, in the initial stage of operation, the removal of TC mainly relied on the adsorption of the material. However, as the reactor operated, microorganisms were enriched on the surface of the catalyst in the reactor, and at this time the microorganisms began to play a role.

[0054] Application Example 3

[0055] Application of a FeAl-NC-Al2O3 water purification catalyst as a fixed-bed filler in Example 1 of the present invention in degrading organic pollutants in water, the method comprising the following steps:

[0056] As Figure 2As shown, a fixed-bed reactor was set up to treat organic pollutants in water. The operating conditions of the fixed-bed reactor are as follows: The organic pollutants are transported to the fixed-bed 3 by a peristaltic pump 2. The flow rate of the organic pollutants (CIP) is 1.8 mL / min, the residence time is 30 min, and the solution is neutral. From Figure 5 it can be obtained that the degradation of BPA gradually improves over the operating days and finally reaches 100%.

[0057] The matrix material of the present invention is inexpensive, has low cost, is convenient to synthesize, has a simple process, and does not generate solid foreign matters such as iron sludge during the reaction process, and does not require a foreign matter removal device. Its granular spherical shape is more suitable for actual water treatment applications than the powder catalyst developed in the laboratory, is convenient for separation from water, and is convenient for recycling.

[0058] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0059] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A preparation method of an alumina-supported copper-doped graphene-like catalyst, characterized in that, It includes the following steps: Step 1: Disperse biomass in a certain volume of deionized water to form suspension A; Step 2: Add aluminum salt and iron salt into suspension A, stir evenly and adjust the pH of the solution to form suspension B; Step 3: Add nitrogen source into suspension B, and after complete dissolution, form impregnation solution C; Step 4: Pour impregnation solution C into a beaker containing alumina balls, let it stand for a certain time, and then dry to obtain dried balls; Step 5: Roast the dried balls in a tubular furnace, cool to room temperature, wash them repeatedly with water, and dry to obtain the immobilized FeAl-NC-Al2O3 water purification catalyst.

2. The preparation method of an alumina-supported copper-doped graphene-like catalyst according to claim 1, characterized in that, In step 1, the biomass is one of silkworm excrement, corn cob, garlic straw, cyclodextrin, and chitosan.

3. The preparation method of an alumina-supported copper-doped graphene-like catalyst according to claim 1, characterized in that, In step 1, the mass-volume ratio of cyclodextrin to deionized water is (1-100) g: 1 L.

4. The preparation method of an alumina-supported copper-doped graphene-like catalyst according to claim 1, wherein, In step 2, the iron salt is one of ferric chloride, ferric nitrate, ferric sulfate, and ferric acetate; the aluminum salt is one of aluminum chloride, aluminum nitrate, and aluminum sulfate; the iron ions in suspension A are 0-200 mmol, and the molar ratio of iron to aluminum is 1:1-5.

5. The preparation method of an alumina-supported copper-doped graphene-like catalyst according to claim 1, characterized in that, In step 3, the nitrogen source is one of urea, dicyandiamide, melamine, and triethylenetetramine; the mass-volume ratio of the nitrogen source to suspension B is (1-300) g: 1 L.

6. The preparation method of an alumina-supported copper-doped graphene-like catalyst according to claim 1, characterized in that, In step 4, the mass-volume ratio of alumina balls to impregnation solution C is (300-900) g: 1 L; the standing temperature is 80 °C, the standing time is 1-24 h, and the drying temperature is 80 °C.

7. The preparation method of an alumina-supported copper-doped graphene-like catalyst according to claim 1, characterized in that, In step 5, the heating rate of the tubular furnace is 5 °C / min, an inert gas is used as the protective gas, the temperature is maintained at 500-900 °C, and the residence time is 2-5 hours.

8. An alumina-supported copper-doped graphene-like catalyst, characterized in that, It is prepared by the preparation method described in claim 1.

9. Application of the alumina-supported copper-doped graphene catalyst described in claim 8 in the degradation of organic pollutants in water.

10. Use of the alumina-supported copper-doped graphene-like catalyst according to claim 9 in the degradation of organic pollutants in water, characterized in that, The organic pollutants include at least one of tetracycline (TC), bisphenol A (BPA), and ciprofloxacin (CIP).

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