阅读说明：本技术 负载型催化剂材料 (Supported catalyst material ) 是由 王猛 马新宇 于 2018-06-25 设计创作，主要内容包括：本发明公开了一种负载型催化剂材料,包括活性组分、催化剂载体和对VOC进行活化的活化剂。本发明提供了一种负载型催化剂材料,假比重为0.1~2.0g/mL、比表面积为200~1500 m<Sup>2</Sup>/g,既具有较高的VOC富集能力,又具有较好的空气动力学通过性,让包含VOC分子的空气可以顺利通过,并且在空气快速流动的情况下能提高空气中VOC如甲醛的吸附量和处理。(The invention discloses a supported catalyst material, which comprises an active component, a catalyst carrier and an activator for activating VOC (volatile organic Compounds). The invention provides a supported catalyst material, wherein the pseudo-specific weight is 0.1 ~ 2.0g/mL, and the specific surface area is 200 ~ 1500m 2 G, both has higher VOCThe air purifier has the advantages of high enrichment capacity and good aerodynamic trafficability, allows air containing VOC molecules to smoothly pass through, and can improve the adsorption amount and treatment of VOC (volatile organic compounds) such as formaldehyde in the air under the condition of quick air flow.)

1. A supported catalyst material comprising an active component, a catalyst support and an activator for activating VOCs.

2. The supported catalyst material of claim 1, wherein the activator is graphene or graphite.

3. The supported catalyst material of claim 2, wherein when the activator is graphene, the graphene is one of single-layer graphene, few-layer graphene, or multi-layer graphene.

4. The supported catalyst material of claim 1, wherein the catalyst material has a bulk specific gravity of 0.1 ~ 2.0.0 g/mL and a specific surface area of 200 ~ 1500m²/g。

5. A supported catalyst material according to claim 4 wherein the bulk specific gravity of the catalyst material is 0.3 ~ 1.0.0 g/mL.

6. A supported catalyst material according to claim 5 wherein the bulk specific gravity of the catalyst material is 0.5 ~ 0.9.9 g/mL.

7. The supported catalyst material of claim 4, wherein the catalyst material has a specific surface area of 500 ~ 1200 m²/g。

8. The supported catalyst material of claim 7, wherein the catalyst material has a specific surface area of 800 ~ 1000 m²/g。

9. The supported catalyst material of claim 1, wherein the active component is platinum, MnO₂A metal platinum-manganese dioxide composite or a metal platinum-zinc oxide composite.

10. The supported catalyst material of claim 1, wherein the catalyst support is one of activated carbon particles or activated carbon fibers.

Technical Field

The invention relates to the field of air purification, in particular to a supported catalyst material.

Background

In 2013, along with the concentrated outbreak of haze in many cities in China, the air pollution problem becomes a social hotspot problem, and the market related to indoor air treatment is rapidly established in a short term. The air quality becomes one of the most concerned civil problems of common people, the indoor environmental pollution caused by frequent haze weather, decoration and fitment and furniture is increasingly aggravated, two major factors urge the indoor environmental protection industry represented by air and in-vehicle purifiers to appear vigorous development trend.

In view of the current increasingly severe air pollution situation, there is a need to research and develop air purification products suitable for the situation of China. Although various air purification products such as air filtration purifiers and indoor fresh air systems have been introduced, various problems still exist in the filter materials which are the most central in the air purification industry.

For gaseous pollutants, the prior art adopts two types of physical and chemical methods for treatment, but the two types of treatment have defects. In the physical method, materials with high specific surface area such as active carbon and the like are adopted for physical adsorption in the prior art, and the materials have high specific surface area and good adsorption performance, but have the problem of adsorption saturation amount; or the catalyst is catalyzed by noble metal and metal oxide, namely the treatment is carried out by a chemical catalytic decomposition method, but the catalytic process of the catalyst is a chemical process, the speed is slow, and the treatment efficiency of gaseous pollutants is very low under the condition of fast flowing of air.

Disclosure of Invention

In order to solve the problems in the prior art, the present invention provides a supported catalyst material which can improve the adsorption amount and treatment efficiency of VOCs such as formaldehyde in the air under the condition of rapid air flow.

The technical scheme adopted by the invention for solving the technical problems is as follows: a supported catalyst material includes an active component, a catalyst support, and an activator that activates VOCs.

Preferably, the activating agent is graphene or graphite. Preferably, the activator is graphene.

Preferably, the graphene is one of single-layer graphene, few-layer graphene or multi-layer graphene.

Preferably, the bulk specific gravity of the catalyst material is 0.1 ~ 2.0.0 g/mL, and the specific surface area is 200 ~ 1500m²/g。

Preferably, the bulk specific gravity of the catalyst material is 0.3 ~ 1.0.0 g/mL.

Preferably, the bulk specific gravity of the catalyst material is 0.5 ~ 0.9.9 g/mL.

Preferably, the specific surface area of the catalyst material is 500 ~ 1200 m²/g。

Preferably, the specific surface area of the catalyst material is 800 ~ 1000 m²/g。

Preferably, the active component is platinum or MnO₂A metal platinum-manganese dioxide composite or a metal platinum-zinc oxide composite.

Preferably, the catalyst carrier is one of activated carbon particles or activated carbon fibers.

In another aspect, the invention provides a method for preparing a supported catalyst by heating a mixture of an active component, a catalyst support and a pore former, wherein the heating temperature is above the boiling point of the pore former.

Preferably, the mixture is extruded by an extruder.

Preferably, the extruder is a single screw extruder or a twin screw extruder.

Preferably, the extruder has 5 temperature sections, which are a first temperature section, a second temperature section, a third temperature section, a fourth temperature section and a fifth temperature section, and the extruder is provided with an exhaust port located in the second temperature section, the third temperature section or the fourth temperature section.

Preferably, the temperature of the first temperature section is 100 ~ 120 ℃, the temperature of the second temperature section is 120 ~ 150 ℃, the temperature of the third temperature section is 150 ~ 180, the temperature of the fourth temperature section is 150 ~ 180 ℃, and the temperature of the fifth temperature section is 150 ~ 160 ℃.

Preferably, the pore former is a volatile liquid or solid. The pore-forming agent is a volatile substance, is not easy to remain, is cheap and easy to obtain, is nontoxic to the catalyst, and can be liquid or solid, such as water, ethanol, methanol, ethyl acetate or dry ice. Preferably, the pore former is water.

Preferably, the rotation speed of the extruder is 20 ~ 100 r/min.

Preferably, the extruder has a length to diameter ratio of 10 ~ 150, where length to diameter is the ratio of the effective length of the screw to the outer diameter of the screw.

Preferably, the active component is platinum or MnO₂A metal platinum-manganese dioxide composite or a metal platinum-zinc oxide composite.

Preferably, the catalyst carrier is one of activated carbon particles or activated carbon fibers.

Preferably, the content of the active component is 0.5 ~ 8wt%, the content of the catalyst carrier is 72 ~ 90.5.5 wt%, and the content of the pore-forming agent is 9 ~ 20 wt%.

Preferably, the mixture of the active component and the catalyst carrier is fully mixed in a mixer at normal temperature in advance, the mixture is transferred to a kneader, added with a pore-forming agent and kneaded for 30 ~ 60min to obtain a kneaded mixture, and the kneaded mixture is added to a single-screw extruder and extruded and molded by the single-screw extruder to obtain the molded supported catalyst.

Preferably, the molded supported catalyst is crushed by a crusher and sieved, the molded supported catalyst is crushed by a particle crusher for 10 ~ 30min, and the molded supported catalyst is sieved by a sieving machine with 30 ~ 100 meshes, so that the bulk specific gravity of the obtained supported catalyst is 0.1 ~ 2.0.0 g/mL.

Preferably, a cocatalyst or activator is added to the mixture.

Preferably, when the mixture is the active component, the catalyst carrier, the cocatalyst and the pore-forming agent, the content of the active component is 0.99 ~ 9.8.8 wt%, the content of the catalyst carrier is 72 ~ 91wt%, the content of the cocatalyst is 0.01 ~ 0.2wt% and the content of the pore-forming agent is 1 ~ 18 wt%.

Preferably, when the mixture comprises an active component, a catalyst support, an activator and a pore-forming agent, the content of the active component is 0.99 ~ 9.8.8 wt%, the content of the catalyst support is 72 ~ 91wt%, the content of the activator is 0.01 ~ 0.2wt%, and the content of the pore-forming agent is 1 ~ 18 wt%.

In another aspect, the present disclosure provides an air purification composite comprising a VOC catalytic reduction layer, wherein the VOC catalytic reduction layer comprises an active component, an activator, and a catalyst support.

Preferably, the active component is platinum or MnO₂One of a metal platinum-manganese dioxide composite or a metal platinum-zinc oxide composite; the activating agent is one of graphene or graphite, and the catalyst carrier is one of activated carbon particles or activated carbon fibers.

Preferably, the catalyst carrier is 90.5wt% ~ 98.99.99 wt%, the active component is 1wt% ~ 9wt%, and the activator is 0.01wt% ~ 0.5.5 wt%.

Preferably, the bulk specific gravity of the VOC catalytic digestion layer is 0.1 ~ 2.0.0 g/mL, and the specific surface area of the VOC catalytic digestion layer is 200 ~ 1500m²/g。

Preferably, the weight range of the VOC catalytic digestion layer is 60 ~ 400g/m and 400g/m²。

As a preferred scheme, one end of the VOC catalytic digestion layer is sequentially stacked with a core high-efficiency filter layer, an intermediate-efficiency filter layer, a coarse-efficiency filter layer and an antibacterial flame-retardant layer, and the other end of the VOC catalytic digestion layer is bonded with the framework layer.

Preferably, the diameter of the long fiber selected by the core high-efficiency filter layer is 0.1 ~ 2 microns, the length of the long fiber main body is 1 ~ 6cm, and the weight of the core high-efficiency filter layer is 10 ~ 100g/m². Preferably, the ionic group is one of a carboxylic acid group, an acrylic acid group, a sulfonic acid group and/or a phosphonic acid group.

Preferably, the middle effect filter layer comprises a main body of long polymer fibers and an additive; the main body of the macromolecular long fiber is polypropylene, and the additive is a graft polymer which takes ethylene-vinyl acetate copolymer as a main chain and is grafted with ionic groups. Preferably, the ionic group is one of a carboxylic acid group, an acrylic acid group, a sulfonic acid group and/or a phosphonic acid group.

Preferably, the coarse filter layer is made of a non-woven fabric fiber material, the non-woven fabric fiber material is one of polypropylene, polyethylene terephthalate, ultra-high molecular weight polyethylene and nylon, and the weight range of the coarse filter layer is 50 ~ 150g/m²。

Preferably, the antibacterial flame-retardant layer comprises a non-woven fabric main body fiber, an antibacterial additive and a flame-retardant additive; the main fiber of the non-woven fabric is one of polypropylene, polyethylene terephthalate, ultra-high molecular weight polyethylene, polyvinyl chloride, bamboo fiber and nylon, the antibacterial additive is nano silver-loaded titanium dioxide, and the flame retardant additive is halogenated phosphate.

Preferably, the framework layer is a non-woven fabric fiber layer, the non-woven fabric fiber layer is one of polypropylene or polyethylene terephthalate non-woven fabrics, and the weight range of the framework layer is 50 ~ 100g/m²。

Preferably, the layers are bonded by physical bonding. The physical bonding mode comprises glue spraying, glue dispensing, ultrasonic hot pressing or thermal bonding.

The invention has the advantages that: 1. the VOC has a certain flow velocity along with air, and an activating agent with rich electrons and high specific surface area, such as graphene or graphite, is adopted to provide electrons for the VOC in advance, so that the reactivity of VOC molecules is improved, the reaction potential barrier is reduced, the catalytic decomposition efficiency of a catalytic system is improved, and the catalytic efficiency of the VOC in the prior art is greatly improved.

2. The activating agent adopts graphene, the combination of active carbon as a catalyst carrier and graphene as the activating agent is not reported in related documents at present, and the two are both composed of carbon elements, so that the activating agent and the catalyst have better compatibility, and the supported catalyst is easy to mix, mold and process.

3. The bulk specific gravity of the powder is 0.1 ~ 2.0.0 g/mL, the specific surface area is 200 ~ 1500m and 1500m²The/g supported catalyst has high VOC enrichment capacity and good aerodynamic trafficability, and allows air containing VOC molecules to smoothly pass through.

4. The catalyst mixture is extruded and molded by an extruder, the temperature and the extrusion speed of each section of the extruder are controlled, and the volatilization speed of the pore-forming agent can be finely adjusted, so that the preset bulk specific gravity of the supported catalyst is obtained.

5. By adopting the multilayer filtering materials for superposition, the extremely high interception efficiency can be achieved, the highest efficiency of the composite material on PM2.5 can reach 99.9995%, and the decomposition efficiency on formaldehyde can reach 80%.

6. The multistage filtration is adopted to carry out grading treatment on solid pollutants, so that the filtration effect is better, the service life and the effect of the material are more durable, and the dust holding capacity can reach 40g/m 2.

7. The layered multi-stage filtration is adopted, namely, multiple functions are realized on materials instead of multi-stage filtration of multiple devices, so that the replacement is more convenient.

Drawings

FIG. 1 is a graph showing the relationship between the specific surface area of catalyst particles and the amount of formaldehyde dynamically adsorbed.

FIG. 2 is a graph showing the relationship between the bulk specific gravity of catalyst particles and the formaldehyde aeration amount.

FIG. 3 is a graph showing the relationship between the mass of catalyst particles and the catalytic efficiency of formaldehyde.

Fig. 4 is a stack view of an air purification composite.

Detailed Description

The present invention will be further described with reference to the structures or terms used herein.

VOC

VOCs are volatile organic compounds that can produce harmful gases, such as formaldehyde, toluene, ammonia, ethylene glycol, esters, and the like. The formaldehyde is a gas pollutant which is extremely harmful to human health, and the formaldehyde in the air comes from the aspects of life, so that the formaldehyde is filled in the industrial production and automobile exhaust, and is small in size, such as furniture, clothes, food, dwellings and places in the middle. The traditional formaldehyde treatment method is basically to remove formaldehyde in a specific space in a targeted manner in a static environment. However, formaldehyde in the air is in a flowing state, and the formaldehyde is also unevenly distributed in the air, so how to remove formaldehyde in the flowing state and unevenly distributed is a problem to be solved urgently at present. However, the treatment with the supported catalyst still has many problems, such as the selection of the active component, the carrier, and the type of the cocatalyst or activator of the supported catalyst, and the control of the specific surface area and the bulk specific gravity of the supported catalyst.

Supported catalyst

The supported catalyst is usually not composed of a single substance but composed of a plurality of substances, some supported catalysts include an active component and a catalyst support, some supported catalysts include an active component, a catalyst support and an activator, and most supported catalysts include an active component, a catalyst support and a cocatalyst, and the active component and the cocatalyst or the activator are uniformly dispersed and supported on the catalyst support. The supported catalyst is generally used for adsorbing and catalyzing pollutant gases in the air, so as to achieve the purpose of purifying the air.

Active component

Reactive species refer to species that are capable of interacting with a reactant to alter the rate at which a chemical reaction approaches equilibrium (but not the equilibrium position of the chemical reaction), without themselves being present in the product. The active component can be a single substance or can be composed of a plurality of substances. The active component may be a metal, a transition metal oxide or sulfide, such as platinum, a metal platinum-manganese dioxide complex or a metal platinum-zinc oxide complex.

Catalyst carrier

The catalyst carrier is a dispersing agent, an adhesive or a support body of the active component, and is a framework for loading the active component. Will be activeThe catalyst in which the component, cocatalyst or activator is supported on the carrier is called a supported catalyst. The active components are supported on the surface of a carrier, which is mainly used to support the active components to give the catalyst specific physical properties, while the carrier itself generally does not have catalytic activity. Most supports are products in the catalyst industry, and commonly used are alumina supports, silica gel supports, activated carbon supports, and certain natural products such as pumice, diatomaceous earth, and the like. The composition of supported catalysts, such as nickel-alumina catalysts for hydrogenation, vanadium oxide-diatomaceous earth catalysts for oxidation, is often referred to by the "active component name-support name". The carrier can be natural or artificial, and is generally divided into two categories of low specific surface area and high specific surface area, wherein the low specific surface area comprises: corundum, silicon carbide, pumice, diatomite, asbestos; of high specific surface area are: SiO 2₂-Al₂O₃Clay, magnesium oxide, silica gel and active carbon. The carrier not only affects the activity and selectivity of the catalyst, but also affects the thermal stability and mechanical strength, and is related to the transfer characteristics of the catalytic reaction process.

Co-catalyst

The cocatalyst is a small amount of substance added into the active component, is an auxiliary component of the active component, has no activity or very low activity, but can change the chemical composition, chemical structure, ionic valence, acidity and alkalinity, lattice structure, surface structure, pore structure, dispersion state, continuous strength and the like of the active component after being added into the active component, thereby improving the activity, selectivity, stability and service life of the active component. Promoters are generally classified into structural type and electronic type promoters according to the difference in mechanism of action. Structural promoters are used primarily to improve the dispersion and stability of active components, such as alumina in iron-potassium oxide-alumina catalysts for ammonia synthesis. The electronic type cocatalyst mainly changes the electronic structure of the active component and promotes the catalytic activity and selectivity.

Activating agent

The graphene comprises single-layer graphene (1 ~ 3 layers), few-layer graphene (3 ~ 9 layers) and multi-layer graphene (more than 10 layers), and only one layer of atomic thickness is the single-layer graphene, the diameter range of the graphene powder is generally 0.001 ~ 1mm, from the manufacturing angle of the graphene, the graphene produced by a physical stripping method can also be used, the graphene produced by an oxidation reduction method is preferred, the graphene produced by the physical stripping method has fewer physical defects, the electron conduction rate is higher, and the free electron density is higher.

For supported catalysts, two important parameters are involved, specific surface area and bulk specific gravity, respectively.

Specific surface area

The specific surface area, i.e., microscopic morphology, refers to the surface area per unit volume (or weight) of the support. The size of the carrier adsorption capacity is intuitively shown, the carrier adsorption capacity is one of important indexes for measuring the performance of the carrier, and the specific surface area has higher capacity of enriching pollutant gases only when being higher. The microscopic form of the catalyst carrier, namely the improvement of the specific surface area, is beneficial to the enrichment of VOC, improves the reactant concentration of VOC and can accelerate the reaction speed. The larger the specific surface area of the catalyst carrier is, the better the VOC enrichment effect is; of course, it is economically undesirable to make the cost too large, otherwise the cost is too high.

Specific gravity of false

The bulk specific gravity, i.e., the macroscopic morphology, is important in terms of unit volume including porosity, and the unit is g/cm³. The macroscopic morphology of the supported catalyst, i.e., the bulk specific gravity of the supported catalyst, determines whether the VOC-containing contaminated air can smoothly pass through the supported catalyst, i.e., the VOC-containing contaminated air permeates into the interior of the catalyst through the voids of the supported catalyst and reacts. It is clear that particles that are too dense do not allow the passage of polluting air and that the catalyst does not effectively come into contact with the VOC molecules. Too loose particles, unit area energyThe weight of the loaded catalyst particles which can be spread is too small, which causes difficulty in practical application.

Pore-forming agent

The pore-forming agent is a volatile substance, has an adhesive effect, is not easy to remain, is cheap and easy to obtain, and is nontoxic to the catalyst. The pore former may be in solid or liquid form, with solid form, such as dry ice, typically dominated by liquid form, such as water, ethanol, methanol, ethyl acetate, and the like.

Extruding machine

The extruder is usually used for plastic molding, and the extruder can fully plasticize and uniformly mix materials by means of pressure and shearing force generated by rotation of a screw rod, and the materials are molded through a die. The material enters the extruder from the hopper, is conveyed forwards under the drive of the rotation of the screw, and is subjected to the heating of the charging barrel and the shearing and compression effects brought by the screw in the forward movement process to melt the material. Extruders can be classified into single screw extruders and twin screw extruders according to the number of screws. The extruder can be divided into three-section, five-section and seven-section screws according to the change characteristics of materials, and the temperature of each section is controllable. The material is extruded by an extruder to be molded, and the temperature of each section of the screw is controllable, so that the material is used for preparing the supported catalyst, the macro morphology of the supported catalyst particles can be controlled, the internal micro morphology is influenced, the specific surface area (micro morphology) of the carrier processed by the extruder is slightly reduced, but the reduction range is small and can be ignored.

Supported catalyst material and preparation method thereof