CN109908967B

CN109908967B - Composite carrier material and preparation method thereof

Info

Publication number: CN109908967B
Application number: CN201711325682.3A
Authority: CN
Inventors: 赵越; 蒋广安; 李宝忠; 马传军; 王雪清
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2017-12-13
Filing date: 2017-12-13
Publication date: 2021-12-07
Anticipated expiration: 2037-12-13
Also published as: CN109908967A

Abstract

The invention provides a composite carrier material and a preparation method thereof. The preparation method comprises the steps of mixing activated carbon and a soluble organic salt solution, introducing a carbonate solution or an alkaline solution into a material A after uniformly mixing, and obtaining a material B, and carrying out solid-liquid separation, drying and roasting to obtain a material C; and mixing the material C with water, introducing carbon dioxide gas for reaction, cooling, performing solid-liquid separation, drying and roasting the separated solid phase to obtain the composite carrier material. The preparation method has simple process and good stability, and can relieve the problem of metal loss.

Description

Composite carrier material and preparation method thereof

Technical Field

The invention relates to a catalytic carrier material and a preparation method thereof, in particular to a composite carrier containing active carbon and a preparation method thereof.

Background

As water resources are increasingly scarce, the national control on the total emission amount of pollutants in water is increasingly strict, the formulation of new standards provides new challenges for the prevention and treatment work of water pollution in China, and most discharged wastewater cannot meet the emission requirements of the new standards. Therefore, the external sewage needs to be deeply treated to achieve standard discharge and even can be recycled, which is of great significance in reducing the discharge amount of discharged pollutants of the wastewater, reducing the pollution discharge cost of enterprises, reducing the consumption of water resources and the like.

More researches are carried out on the aspect of treating the organic polluted wastewater difficult to degrade at home and abroad, and the advanced oxidation technology (AOP) stands out in the past two decades with huge potential and unique advantages. Compared with other traditional water treatment methods, the AOP technology is free radical chain reaction and has the advantages of short reaction time, high reaction speed and over-reactionThe process can be controlled, has no selectivity and the like, can completely degrade various organic pollutants, and does not generate secondary pollution. Hydrogen peroxide and ozone are commonly used AOP oxidants. The hydrogen peroxide generates hydroxyl radicals by a Fenton method, but the used homogeneous catalyst has the problems of more used medicaments, difficult recovery and the like, and is easy to cause secondary pollution. The ozone oxidation treatment of wastewater is an advanced oxidation technology, but the ozone single oxidation technology is limited by the defects of high selectivity of organic matters, incapability of thoroughly oxidizing the organic matters and the like, and is difficult to achieve the best treatment effect. The catalytic oxidation of ozone can convert ozone in water solution into hydroxyl radical (OH) with higher oxidation potential by the action of catalyst, and the OH reacts with most organic matters almost without selectivity and the reaction rate is 10⁶～10¹⁰ M^-1• s^-1And the reaction rate is about 7 orders of magnitude higher than that of ozone and organic matters. The organic matters which are difficult to be oxidized or degraded by ozone alone can be oxidized at normal temperature and normal pressure so as to purify the water quality. The catalytic ozonation can overcome the defect of single ozonation, thereby becoming a novel advanced oxidation technology with more practical value.

The key point of the ozone catalytic oxidation technology is the development of a catalyst, the used catalyst is divided into a homogeneous phase catalyst and a heterogeneous phase catalyst, and similar to a Fenton method, the homogeneous catalyst has the problems of difficult recovery and easy secondary pollution, so the research is mostly concentrated on the heterogeneous catalyst.

The heterogeneous solid catalyst is mainly a catalyst which is formed by taking active carbon, molecular sieve, amorphous alumina, titanium dioxide and the like as carriers and taking one or more of alkali metal, alkaline earth metal, transition metal or Pt and Pd noble metal as active components. The active carbon is a kind of microcrystal carbon which is made of carbon-containing substance and has the advantages of black color, developed pores, large specific surface area and strong adsorption capacity. The activated carbon has stable property, is acid-resistant, alkali-resistant and heat-resistant, is insoluble in water or organic solvent, is easy to regenerate, is an environment-friendly adsorbent, and is widely applied to the fields of treatment of industrial three wastes, food, medicine, carriers, semiconductors, batteries, electric energy storage and the like. At present, activated carbon is mostly selected as a carrier for a multiphase solid catalyst for wastewater treatment, but the catalyst prepared by selecting activated carbon loaded metal has poor wear resistance and low mechanical strength, and the loaded metal is easy to run off, so that the application effect of the activated carbon catalyst is reduced.

CN200610089575.0 discloses an activated carbon-supported copper oxide catalyst and a preparation method thereof, wherein the preparation method of the catalyst comprises the following steps: soaking the activated carbon in 10% NaOH solution for 24h, filtering, and washing with deionized water to neutrality; then 10% HNO is used₃Soaking the solution for 24 hours, filtering, washing the solution to be neutral by deionized water, putting the solution into a drying oven, and drying the solution at 100-110 ℃; adding 0.2 to 0.3mol/L of Cu (NO)₃)₂Adding the treated active carbon into the solution, fully stirring, and dropwise adding 20% NaHCO₃And (3) until a large amount of precipitate is generated, curing for 24h, filtering, washing with deionized water until no metal ions are separated out, drying in an oven at 100-110 ℃ to obtain an activated carbon-supported copper oxide solid, and activating at 270-280 ℃ for 2.5h to obtain the activated carbon-supported copper oxide catalyst.

CN201210323265.6 discloses an activated carbon/alumina composite catalyst carrier and a preparation method thereof, and the activated carbon/alumina composite catalyst carrier is prepared by mixing acid-washed activated carbon with gamma-alumina, adding a composite auxiliary agent, kneading, extruding and roasting in nitrogen atmosphere. The material is still a physical mixture of alumina and activated carbon, the alumina and the activated carbon are not uniformly dispersed, and the comprehensive performance of the material needs to be further improved.

CN201510298192.3 discloses a method and equipment for preparing a surface vitrified carbon adsorption material, which comprises the steps of firstly mixing activated carbon powder and a binder to form activated carbon core particles, then taking the activated carbon core particles as mother spheres, uniformly adhering a vitrified material on the outer surfaces of the activated carbon core particles, drying, preheating at a medium temperature, sintering at a high temperature, and discharging at room temperature to obtain the activated carbon particles with vitrified surfaces. The active carbon in the particles prepared in this way cannot be directly contacted with the wastewater, and the catalytic performance of the particles is weakened.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a catalytic carrier material and a preparation method thereof, wherein the carrier is simple in preparation process, good in stability, high in COD removal capacity and capable of relieving the problem of metal loss.

The invention provides a composite carrier, which comprises activated carbon and basic carbonate, wherein the basic carbonate is distributed on the outer surface of the activated carbon, and the activated carbon accounts for 35-90%, preferably 40-80% of the total weight of the composite carrier; the basic carbonate accounts for 10-65% of the total weight of the composite carrier, and preferably 20-60%; the basic carbonate is basic magnesium carbonate or a mixture of the basic calcium carbonate and the basic magnesium carbonate.

The active carbon used in the invention is powdery active carbon, the granularity is 150-300 meshes, and the specific surface area is 500-3000 m²A pore volume of 0.5-1.8 cm³(ii)/g, the average pore diameter is 0.5 to 4.0nm, and the pore volume of pores having a pore diameter of 1 to 2nm accounts for 90% or more of the total pore volume.

In the composite carrier, the activated carbon can be selected from conventional powdered activated carbon commodities, such as various wood activated carbons, shell activated carbons and coal-based activated carbons; or can be selected from various activated carbon products obtained by conventional preparation methods of wood materials, mineral materials, plastics and wastes, such as wood, sawdust, charcoal, coconut shells, fruit pits, fruit shells, coal carbon, coal gangue, petroleum coke, petroleum pitch, polyvinyl chloride, polypropylene, organic resin, waste tires, residual sludge and the like.

In the composite carrier of the present invention, the properties of the composite carrier are as follows: the specific surface area is 150-1500 m²A pore volume of 0.1 to 1.2 cm/g³(ii)/g, the average pore diameter is 1-8 nm.

In the composite carrier, the composite carrier is provided with two-stage pore channels, the pore diameter of a first-stage pore channel is 0.5-2 nm, the pore diameter of a second-stage pore channel is 2-50 nm, wherein the pore volume of the pore with the pore diameter of 0.5-2 nm accounts for less than 85% of the total pore volume, preferably 70-80%, and the pore volume of the pore with the pore diameter of 2-50 nm accounts for more than 15% of the total pore volume, preferably 20-30%.

In the composite carrier, when the basic carbonate is a mixture of basic calcium carbonate and basic magnesium carbonate, the basic calcium carbonate and the basic magnesium carbonate can be mixed in any proportion.

The second aspect of the present invention provides a method for preparing a composite carrier, the method comprising the following steps:

(1) mixing activated carbon and a soluble organic salt solution uniformly to obtain a material A, wherein the soluble organic salt solution is a soluble organic magnesium salt solution or a mixed solution of a soluble organic calcium salt solution and a soluble organic magnesium salt solution;

(2) introducing a carbonate solution or an alkaline solution into the material A obtained in the step (1), uniformly mixing, and standing to obtain a material B;

(3) performing solid-liquid separation on the material B obtained in the step (2), and drying and roasting a solid phase obtained by separation to obtain a material C;

(4) and (4) mixing the material C obtained in the step (3) with water, introducing carbon dioxide gas for reaction, cooling, performing solid-liquid separation, and drying and roasting the separated solid phase to obtain the composite carrier.

In the preparation method, the activated carbon in the step (1) is powdered activated carbon, the granularity is 150-300 meshes, and the specific surface area is 500-3000 m²A pore volume of 0.5-1.8 cm³(ii)/g, the average pore diameter is 0.5 to 4.0nm, and the pore volume of pores having a pore diameter of 1 to 2nm accounts for 90% or more of the total pore volume. The activated carbon can be selected from conventional powdered activated carbon commodities, such as various wood activated carbons, shell activated carbons and coal-based activated carbons; or can be selected from various activated carbon products obtained by conventional preparation methods of wood materials, mineral materials, plastics and wastes, such as wood, sawdust, charcoal, coconut shells, fruit pits, fruit shells, coal carbon, coal gangue, petroleum coke, petroleum pitch, polyvinyl chloride, polypropylene, organic resin, waste tires, residual sludge and the like.

In the preparation method of the invention, the soluble organic calcium salt in the step (1) is one or more of calcium gluconate, calcium acetate, calcium lactate, calcium amino acid, calcium L-aspartate and calcium L-threonate, and preferably adopts calcium gluconate or calcium lactate.

In the preparation method of the invention, the soluble organic magnesium salt in the step (1) is one or more of magnesium gluconate, magnesium acetate, magnesium lactate, magnesium amino acid, magnesium L-aspartate and magnesium L-threonate, and preferably magnesium gluconate or magnesium lactate is adopted.

In the preparation method, the activated carbon and the soluble organic salt in the step (1) are mixed according to the ratio of C: m²⁺The molar ratio is 4.3-84.7: 1, and the ratio of C: m²⁺The molar ratio is 10-60: 1, wherein M represents Mg or Ca and Mg.

In the preparation method, the carbonate in the step (2) is one or more of ammonium carbonate, potassium carbonate and sodium carbonate, and preferably ammonium carbonate; the concentration of the carbonate solution is 0.1-1.0 mol/L.

In the preparation method of the invention, the carbonate dosage in the step (2) is CO₃ ^2-：M²⁺The molar ratio is 1-1.2: 1, and CO is preferably selected₃ ^2-：M²⁺The molar ratio is 1:1, wherein M represents Mg, or Ca and Mg. .

In the preparation method of the invention, the alkaline solution in the step (2) is an inorganic alkaline solution, and specifically can be ammonia water, sodium hydroxide or potassium hydroxide.

In the preparation method, an alkaline solution is introduced into the material A obtained in the step (1) in the step (2), and then the pH value is adjusted to 8-9.

In the preparation method, the dosage of the alkaline solution in the step (2) is OH^-：M²⁺The molar ratio is 2-4: 1, and OH is preferred^-：M²⁺The molar ratio is 2-2.5: 1, wherein M represents Mg or Ca and Mg.

In the preparation method, the drying temperature in the step (3) is 70-110 ℃, preferably 80-100 ℃, and the drying time is 2-6 hours, preferably 3-4 hours.

In the preparation method, the roasting in the step (3) is carried out in nitrogen or inert atmosphere, wherein the inert atmosphere is one of argon and helium. In the step (3), the roasting temperature is 500-1200 ℃, preferably 600-900 ℃, and the roasting time is 2-8 hours, preferably 3-5 hours.

In the preparation method, the material C in the step (4) is mixed with water at the temperature of 60-100 ℃.

In the preparation method, the partial pressure of the carbon dioxide in the step (4) is 0.08-1.0 MPa.

In the preparation method, the reaction end point pH in the step (4) is 7.0-10.0, preferably 8.0-9.0.

In the preparation method, the reaction temperature in the step (4) is 15-150 ℃.

In the preparation method, the drying temperature in the step (4) is 40-100 ℃, preferably 50-60 ℃, and the drying time is 3-24 hours, preferably 6-8 hours.

In the preparation method, the roasting in the step (4) is carried out in nitrogen or inert atmosphere, and the inert atmosphere is one of argon and helium. In the step (4), the roasting temperature is 80-220 ℃, the roasting time is 2-12 h, and the roasting time is preferably 3-8 h, wherein the roasting time is preferably 150-200 ℃.

In the preparation method of the present invention, the solid-liquid separation in step (3) and step (4) can adopt any scheme in the art that can realize solid-liquid separation, such as solid-liquid separation by filtration.

In the method of the present invention, the mixing may be performed by any of stirring, shearing, ultrasonic treatment, and the like.

Compared with the prior art, the invention provides the composite carrier containing the activated carbon and the preparation method thereof, the basic magnesium carbonate or the basic calcium carbonate and the basic magnesium carbonate are introduced into the outer surface of the activated carbon in the composite carrier, and compared with a pure activated carbon carrier, the relative content of the activated carbon in the carrier is reduced, so that the utilization rate of free radicals can be improved, and the problems that the generation of hydroxyl free radicals is accelerated, the collision probability among the free radicals is increased and the concentration of the free radicals is weakened due to the overhigh content of the activated carbon in the existing pure activated carbon catalyst are solved. The basic magnesium carbonate is introduced into the outer surface of the composite carrier, or hydroxyl contained in the basic calcium carbonate and the basic magnesium carbonate is beneficial to promoting the ozone decomposition to generate hydroxyl free radicals, and further initiates a free radical chain reaction, and the utilization efficiency of the hydroxyl free radicals can be improved to the maximum degree by adjusting the content of the basic magnesium carbonate or the basic calcium carbonate and the basic magnesium carbonate to control the content of the hydroxyl. When the active metal supported active carbon composite carrier is used for wastewater treatment, the basic calcium carbonate and the basic magnesium carbonate can adsorb active metal ions dissolved out from the catalyst, so that secondary pollution caused by the active metal ions is avoided.

According to the preparation method of the composite carrier, the macromolecular organic magnesium salt or the macromolecular organic calcium salt and the macromolecular organic magnesium salt solution are mixed with the active carbon, and molecules of the macromolecular organic magnesium salt and the macromolecular organic calcium salt are difficult to enter pores of the active carbon, so that calcium ions and magnesium ions are almost completely attached to the surface of the active carbon, the organic calcium salt and the organic magnesium salt solution are prevented from entering the pores of the active carbon, and the generated basic calcium carbonate and basic magnesium carbonate can be prevented from blocking the pores and influencing the performance of the carrier. The preparation process of the composite carrier is an in-situ generation process of organic calcium salt/organic magnesium salt-calcium carbonate/magnesium (calcium hydroxide/magnesium) -basic calcium carbonate/magnesium, the basic calcium carbonate/magnesium is firmly attached to the outer surface of the active carbon, the mechanical mixing of the active carbon and the basic calcium carbonate/magnesium is more uniform and firm, and the defect that pore channels are blocked due to in-situ generation in pores is avoided. Meanwhile, organic components in the organic calcium/magnesium salt can generate part of carbon in the roasting stage, the part of carbon can play a role of an adhesive, and the generated calcium/magnesium salt is organically connected with the original activated carbon carrier, so that the firmness between the basic calcium/magnesium carbonate and the activated carbon in the composite carrier is improved, the strength of the formed carrier is enhanced, and the abrasion is reduced.

Detailed Description

The preparation process of the present invention is further illustrated below with reference to specific examples, but the scope of the present invention is not limited to these examples.

The specific surface area and the pore volume of the product are measured by adopting a low-temperature liquid nitrogen physical adsorption method.

The specific surface area of the commercially available activated carbon used in the present invention was 828m²G, pore volume 0.8cm³The average pore radius is 2.1nm, the iodine adsorption value is 700mg/g, and the granularity is 200 meshes.

Example 1

50g of activated carbon powderAdding the mixture into 200g of magnesium gluconate solution with the mass fraction of 18%, slowly stirring, and soaking for 4 hours; slowly adding 290mL of 0.6mol/L sodium hydroxide solution dropwise under stirring to generate magnesium hydroxide precipitate, stirring, standing for 2 hours, filtering, drying at 80 ℃ for 12 hours, and roasting at 1100 ℃ for 3 hours under the protection of nitrogen to obtain the activated carbon-magnesium oxide compound. Adding the obtained compound into 200g of distilled water with the temperature of 90 ℃, introducing CO after 2h₂And (3) performing natural cooling, filtering, drying at 70 ℃ for 8h, and roasting at 180 ℃ for 4h under the protection of nitrogen to obtain an activated carbon and basic magnesium carbonate composite carrier A1, wherein the pressure of the gas is 0.18MPa, the temperature of the gas is 150 ℃, the final pH value is controlled to be 7.5, and the properties of the composite carrier are shown in Table 1.

And (3) soaking the obtained carrier A1 in copper nitrate solution in the same volume to prepare a catalyst loaded with 6wt% of copper oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst C1.

Example 2

Adding 50g of activated carbon powder into 250g of L magnesium lactate solution with the mass fraction of 19.2%, slowly stirring, and soaking for 4 hours; slowly adding 270mL of ammonium carbonate solution with the concentration of 0.7mol/L dropwise under stirring to generate magnesium carbonate precipitate, stirring, standing for 2 hours, filtering, drying at 80 ℃ for 12 hours, and roasting at 1100 ℃ for 3 hours under the protection of nitrogen to obtain the activated carbon-magnesium oxide compound. Adding the obtained compound into 200g of distilled water with the temperature of 85 ℃, introducing CO after 2h₂And (3) controlling the end point pH to be 8.0 at 90 ℃ under the pressure of 0.36MPa, naturally cooling, filtering, drying at 70 ℃ for 8h, and roasting at 200 ℃ for 2h under the protection of argon to obtain an activated carbon and basic magnesium carbonate composite carrier A2, wherein the properties of the composite carrier are shown in Table 1.

And (3) soaking the obtained carrier A2 in an iron nitrate solution in the same volume to prepare a catalyst loaded with 15wt% of iron oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst C2.

Example 3

Adding 100g of activated carbon powder into 300g of a magnesium L-aspartate solution with the mass fraction of 10%, slowly stirring, and soaking for 4 hours; slowly dropwise adding 210mL of 1.0mol/L ammonia water under stirring to generate magnesium carbonate precipitate, stirring, standing for 2 hr, filtering, and drying at 80 deg.C for 12 hrAnd roasting for 3 hours at 1100 ℃ under the protection of nitrogen to obtain the active carbon-magnesium oxide compound. Adding the obtained compound into 200g of distilled water with the temperature of 90 ℃, introducing CO after 1h₂And (3) controlling the end point pH to be 9.0 at the temperature of 110 ℃ under the pressure of 0.15MPa, naturally cooling, filtering, drying at 70 ℃ for 8h, and roasting at 200 ℃ for 2h under the protection of argon to obtain an activated carbon and basic magnesium carbonate composite carrier A3, wherein the properties of the composite carrier are shown in Table 1.

And (3) soaking the obtained carrier A3 in an iron nitrate solution in the same volume to prepare a catalyst loaded with 10wt% of iron oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst C3.

Example 4

Adding 100g of activated carbon powder into 300g of mixed solution of magnesium gluconate with the mass fraction of 8.5% and calcium gluconate with the mass fraction of 7.2%, slowly stirring, and soaking for 4 hours; slowly adding 225mL of ammonium carbonate solution with the concentration of 0.5mol/L dropwise under stirring to generate carbonate precipitate, stirring, standing for 2 hours, filtering, drying at 80 ℃ for 12 hours, and roasting at 900 ℃ for 3 hours under the protection of nitrogen to obtain the activated carbon-calcium oxide-magnesium oxide compound. Adding the obtained compound into 200g of distilled water with the temperature of 80 ℃, introducing CO after 2h₂And (3) performing natural cooling, filtering, drying at 70 ℃ for 3h, and roasting at 180 ℃ for 2h under the protection of nitrogen to obtain a composite carrier A4 of activated carbon, basic calcium carbonate and basic magnesium carbonate, wherein the pressure is 0.22MPa, the temperature is 120 ℃, the end point pH is controlled to be 8.2, and the properties of the composite carrier are shown in Table 1.

And (3) soaking the obtained carrier A4 in a copper nitrate solution in the same volume to prepare a catalyst loaded with 10wt% of copper oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst C4.

Example 5

Adding 100g of activated carbon powder into 300g of mixed solution of 14.6 percent of magnesium gluconate and 5.1 percent of L-calcium lactate in mass fraction, slowly stirring and soaking for 4 hours; slowly dropwise adding 200mL of 0.8mol/L sodium carbonate solution under stirring to generate carbonate precipitate, stirring, standing for 2 hours, filtering, drying at 80 ℃ for 12 hours, and roasting at 1100 ℃ for 3 hours under the protection of nitrogen to obtain the activated carbon-calcium oxide-magnesium oxide compound. Adding the obtained complexAdding into 200g of 90 deg.C distilled water, introducing CO after 1 hr₂And (3) gas under the pressure of 0.30MPa and at the temperature of 140 ℃, controlling the end point pH to be 7.7, naturally cooling, filtering, drying at 50 ℃ for 6 hours, and roasting at 140 ℃ for 4 hours under the protection of nitrogen to obtain a composite carrier A5 of the activated carbon, the basic calcium carbonate and the basic magnesium carbonate, wherein the properties of the composite carrier are shown in Table 1.

And (3) soaking the obtained carrier A5 in a cerium nitrate solution in the same volume to prepare a catalyst loaded with 4 wt% of cerium oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst C5.

Example 6

Adding 50g of activated carbon powder into 300g of mixed solution of 12.8 percent of magnesium L-aspartate and 6.3 percent of calcium acetate respectively, slowly stirring and soaking for 4 hours; slowly dropwise adding 570mL of potassium hydroxide solution with the concentration of 0.9mol/L under stirring to generate hydroxide precipitate, stirring, standing for 2 hours, filtering, drying at 80 ℃ for 12 hours, and roasting at 1100 ℃ for 3 hours under the protection of nitrogen to obtain the activated carbon-calcium oxide-magnesium oxide compound. Adding the obtained compound into 200g of distilled water with the temperature of 85 ℃, introducing CO after 2h₂And (3) performing natural cooling, filtering, drying at 70 ℃ for 4h, and roasting at 160 ℃ for 3h under the protection of nitrogen to obtain a composite carrier A6 of activated carbon, basic calcium carbonate and basic magnesium carbonate, wherein the pressure is 0.26MPa, the temperature is 120 ℃, the end point pH is controlled to be 8.5, and the properties of the composite carrier are shown in Table 1.

And (3) soaking the obtained carrier A6 in copper nitrate solution in the same volume to prepare a catalyst loaded with 5wt% of copper oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst C6.

Example 7

Adding 50g of activated carbon powder into 200g of mixed solution of 3.3 percent of L-magnesium lactate and 6.1 percent of L-calcium aspartate by mass percent respectively, slowly stirring, and soaking for 4 hours; slowly dripping 220mL of ammonium carbonate solution with the concentration of 0.3mol/L under stirring to generate carbonate precipitate, stirring, standing for 2 hours, filtering, drying at 80 ℃ for 12 hours, and roasting at 900 ℃ for 3 hours under the protection of nitrogen to obtain the activated carbon-calcium oxide-magnesium oxide compound. Adding the obtained compound into 200g of distilled water with the temperature of 75 ℃, introducing CO after 4h₂Gas pressureThe preparation method comprises the steps of controlling the end point pH to be 8.0 at 100 ℃ under the condition of 0.40MPa, naturally cooling, filtering, drying at 50 ℃ for 6 hours, and roasting at 150 ℃ for 4 hours under the protection of nitrogen to obtain the composite carrier A7 of the activated carbon, the basic calcium carbonate and the basic magnesium carbonate, wherein the properties of the composite carrier are shown in Table 1.

And (3) soaking the obtained carrier A7 in an iron nitrate solution in the same volume to prepare a catalyst loaded with 10wt% of iron oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst C7.

TABLE 1 vector A1-A7 Properties

Comparative example 1

Substantially the same as in example 1 except that the magnesium gluconate solution having a mass fraction of 18% was replaced with a magnesium nitrate solution having a mass fraction of 4.3%, and the other conditions were not changed, the support DA1 and the catalyst DC1 were obtained. The properties of the vector are shown in table 2.

Comparative example 2

Substantially the same as example 4, except that the mixed solution of magnesium gluconate and calcium gluconate of 8.5% and 7.2% by mass respectively was replaced with a calcium chloride solution of 4% by mass, and the other conditions were not changed, the support DA2 and the catalyst DC2 were obtained. The properties of the vector are shown in table 2.

Comparative example 3

The active carbon powder, basic magnesium carbonate and basic calcium carbonate powder are mechanically mixed according to the mass ratio of 60:25:15 to prepare a composite carrier DA3, and the properties of the carrier are shown in Table 2. And (3) soaking the obtained carrier DA3 in a copper nitrate solution in the same volume to prepare a catalyst loaded with 5wt% of copper oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst DC 3.

Comparative example 4

Mechanically mixing activated carbon powder and basic magnesium carbonate powder according to a mass ratio of 40:60 to prepare a composite carrier DA4, wherein the properties of the carrier are shown in Table 2. And (3) soaking the obtained carrier DA4 in a copper nitrate solution in the same volume to prepare a catalyst loaded with 5wt% of copper oxide, tabletting, and crushing to 20-40 meshes to obtain the catalyst DC 4.

TABLE 2 comparative examples 1-4 comparison of results

Evaluation test: the catalyst prepared from the catalyst support of the present invention described above and the catalyst prepared from the comparative support were evaluated.

A certain phenol-formaldehyde (1: 1) solution is used as a raw material, a catalyst is filled in a bubbling bed reactor, ozone is used as an oxidation medium, and the intermittent treatment is carried out on the catalyst, wherein the COD of the phenol-formaldehyde solution is 226 mg/L.

The treatment conditions are normal temperature and normal pressure, the dosage of the catalyst is 50g, the wastewater is 500mL, and the ozone amount is 9.2g/m³The aeration time was 40min, and the treatment results are shown in Table 3.

Table 3 comparison of catalyst evaluation results

Catalyst and process for preparing same	C1	C2	C3	C4	C5	C6	C7	DC1	DC2	DC3	DC4
												COD removal rate%	89.6	87.3	96.3	95.8	91.9	86.4	93.4	77.3	78.9	62.4	65.7
Active metal ion concentration, mg/L	0.42	0.48	0.41	0.49	0.23	0.35	0.40	0.55	0.73	0.72	0.70

Claims

1. A composite carrier comprises activated carbon and basic carbonate, wherein the basic carbonate is distributed on the outer surface of the activated carbon, the activated carbon accounts for 35-90% of the total weight of the composite carrier, and the basic carbonate accounts for 10-65% of the total weight of the composite carrier; the basic carbonate is basic magnesium carbonate or a mixture of the basic calcium carbonate and the basic magnesium carbonate, and the preparation method of the composite carrier comprises the following steps:

(1) mixing activated carbon and a soluble organic salt solution uniformly to obtain a material A, wherein the soluble organic salt solution is a soluble organic magnesium salt solution, or a soluble organic calcium salt solution and a soluble organic magnesium salt solution;

2. The composite carrier of claim 1, wherein: the active carbon accounts for 40-80% of the total weight of the composite carrier; the basic carbonate accounts for 20-60% of the total weight of the composite carrier.

3. The composite carrier according to claim 1 or 2, wherein: the activated carbon is powdered activated carbon, the granularity is 150-300 meshes, and the specific surface area is 500-3000 m²A pore volume of 0.5-1.8 cm³(ii)/g, the average pore diameter is 0.5 to 4.0nm, and the pore volume of pores having a pore diameter of 1 to 2nm accounts for 90% or more of the total pore volume.

4. The composite carrier according to claim 1 or 2, wherein: the properties of the composite carrier are as follows: the specific surface area is 150-1500 m²A pore volume of 0.1 to 1.2 cm/g³(ii)/g, the average pore diameter is 1-8 nm.

5. The composite carrier according to claim 1 or 2, wherein: the composite carrier is provided with two-stage pore channels, the pore diameter of a first-stage pore channel is 0.5-2 nm, the pore diameter of a second-stage pore channel is 2-50 nm, the pore volume of the pore with the pore diameter of 0.5-2 nm accounts for less than 85% of the total pore volume, and the pore volume of the pore with the pore diameter of 2-50 nm accounts for more than 15% of the total pore volume.

6. The composite carrier according to claim 1 or 2, wherein: the composite carrier is provided with two-stage pore channels, the pore diameter of a first-stage pore channel is 0.5-2 nm, the pore diameter of a second-stage pore channel is 2-50 nm, wherein the pore volume of pores with the pore diameter of 0.5-2 nm accounts for 70% -80% of the total pore volume, and the pore volume of pores with the pore diameter of 2-50 nm accounts for 20% -30% of the total pore volume.

7. A preparation method of a composite carrier comprises the following steps:

(4) mixing the material C obtained in the step (3) with water, introducing carbon dioxide gas for reaction, cooling, performing solid-liquid separation, and drying and roasting a solid phase obtained by separation to obtain a composite carrier;

the soluble organic calcium salt in the step (1) is one or more of calcium gluconate, calcium acetate, calcium lactate, calcium amino acid, calcium L-aspartate and calcium L-threonate;

the soluble organic magnesium salt in the step (1) is one or more of magnesium gluconate, magnesium acetate, magnesium lactate, magnesium amino acid, magnesium L-aspartate and magnesium L-threonate.

8. The method of claim 7, wherein: in the step (1), the activated carbon is powdered activated carbon, the granularity is 150-300 meshes, and the specific surface area is 500-3000 m²A pore volume of 0.5-1.8 cm³(ii)/g, the average pore diameter is 0.5 to 4.0nm, and the pore volume of pores having a pore diameter of 1 to 2nm accounts for 90% or more of the total pore volume.

9. The method of claim 7, wherein: in the step (1), the soluble organic calcium salt is calcium gluconate or calcium lactate.

10. The method of claim 7, wherein: in the step (1), the soluble organic magnesium salt is magnesium gluconate or magnesium lactate.

11. The method of claim 7, wherein: in the step (1), the activated carbon and the soluble organic salt are mixed according to the ratio of C: m²⁺Mixing at a molar ratio of 4.3-84.7: 1, wherein M represents Mg or Ca and Mg.

12. The production method according to claim 7 or 11, characterized in that: in the step (1), the activated carbon and the soluble organic salt are mixed according to the ratio of C: m²⁺Mixing at a molar ratio of 10-60: 1, wherein M represents Mg or Ca and Mg.

13. The method of claim 7, wherein: and (3) in the step (2), the carbonate is one or more of ammonium carbonate, potassium carbonate and sodium carbonate.

14. The production method according to claim 7 or 13, characterized in that: in the step (2), the carbonate is ammonium carbonate.

15. The method of claim 7, wherein: the concentration of the carbonate solution in the step (2) is 0.1-1.0 mol/L.

16. The method of claim 7, wherein: the carbonate dosage in the step (2) is CO₃ ^2-：M² ⁺The molar ratio is 1-1.2: 1, and M represents Mg or Ca and Mg.

17. The production method according to claim 7 or 16, characterized in that: the carbonate dosage in the step (2) is CO₃ ^2-：M²⁺The molar ratio is 1:1, and M represents Mg or Ca and Mg.

18. The method of claim 7, wherein: the alkaline solution in the step (2) is an inorganic alkaline solution.

19. The production method according to claim 7 or 18, characterized in that: and (3) in the step (2), the alkaline solution is ammonia water, sodium hydroxide or potassium hydroxide.

20. The method of claim 7, wherein: and (3) introducing an alkaline solution into the material A obtained in the step (1) in the step (2), and then adjusting the pH value to 8-9.

21. The method of claim 7, wherein: the dosage of the alkaline solution in the step (2) is OH^-：M²⁺The molar ratio is 2-4: 1, wherein M represents Mg or Ca and Mg.

22. The production method according to claim 7 or 21, characterized in that: the dosage of the alkaline solution in the step (2) is OH^-：M²⁺The molar ratio is 2-2.5: 1, wherein M represents Mg or Ca and Mg.

23. The method of claim 7, wherein: in the step (3), the drying temperature is 70-110 ℃, and the drying time is 2-6 h.

24. The production method according to claim 7 or 23, characterized in that: in the step (3), the drying temperature is 80-100 ℃, and the drying time is 3-4 h.

25. The method of claim 7, wherein: and (4) roasting in the step (3) in an inert atmosphere, wherein the inert atmosphere is one of nitrogen, argon and helium.

26. The method of claim 7, wherein: in the step (3), the roasting temperature is 500-1200 ℃, and the roasting time is 2-8 h.

27. The production method according to claim 7 or 26, characterized in that: in the step (3), the roasting temperature is 600-900 ℃, and the roasting time is 3-5 h.

28. The method of claim 7, wherein: and (4) mixing the material C with water at the temperature of 60-100 ℃.

29. The method of claim 7, wherein: in the step (4), the partial pressure of the carbon dioxide is 0.08-1.0 MPa.

30. The method of claim 7, wherein: and (4) the pH value of the reaction end point in the step (4) is 7.0-10.0.

31. The production method according to claim 7 or 30, wherein: and (4) the pH value of the reaction end point in the step (4) is 8.0-9.0.

32. The method of claim 7, wherein: the reaction temperature in the step (4) is 15-150 ℃.

33. The method of claim 7, wherein: in the step (4), the drying temperature is 40-100 ℃, and the drying time is 3-24 h.

34. The production method according to claim 7 or 33, characterized in that: in the step (4), the drying temperature is 50-60 ℃, and the drying time is 6-8 h.

35. The method of claim 7, wherein: and (4) roasting in an inert atmosphere, wherein the inert atmosphere is one of nitrogen, argon and helium.

36. The method of claim 7, wherein: in the step (4), the roasting temperature is 80-220 ℃, and the roasting time is 2-12 h.

37. The production method according to claim 7 or 36, wherein: in the step (4), the roasting temperature is 150-200 ℃, and the roasting time is 3-8 h.