阅读说明：本技术 一种气体吸附剂及其制备方法和应用 (Gas adsorbent and preparation method and application thereof ) 是由 满毅 黄文氢 王斌 陈松 于 2018-08-23 设计创作，主要内容包括：本发明公开了一种气体吸附剂及其制备方法和应用,所述气体吸附剂包括载体和活性组分,活性组分包括：组分a,其为多孔材料；组分b,其为第VIII族金属或其氧化物；任选地组分c,其为第IVB族金属氧化物、第VB族金属氧化物和第VIB族金属氧化物中的一种或多种；任选地组分d,其为第IA族金属盐。通过控制温度,该气体吸附剂可以实现对乙烯和乙炔的吸附和脱附,可用于程序升温表面反应中测定乙烯和乙炔的含量。(The invention discloses a gas adsorbent and a preparation method and application thereof, wherein the gas adsorbent comprises a carrier and active components, and the active components comprise: component a, which is a porous material; a component b which is a group VIII metal or an oxide thereof; optionally a component c which is one or more of a group IVB metal oxide, a group VB metal oxide and a group VIB metal oxide; optionally component d which is a group IA metal salt. By controlling the temperature, the gas adsorbent can realize the adsorption and desorption of ethylene and acetylene, and can be used for measuring the contents of ethylene and acetylene in the temperature programmed surface reaction.)

1. A gas sorbent comprising a carrier and an active component, the active component comprising:

component a, which is a porous material;

a component b which is a group VIII metal or an oxide thereof;

optionally, component c, which is one or more of a group IVB metal oxide, a group VB metal oxide, and a group VIB metal oxide;

optionally, component d, which is a group IA metal salt.

2. The gas sorbent according to claim 1, characterized in that the gas sorbent has a content of component a of 0.5-3.0 wt. -%, preferably 1.5-2.0 wt. -%, based on the total mass of the gas sorbent; the content of component b is 0.5 to 3.0 wt.%, preferably 1.0 to 1.5 wt.%; the content of component c is 0 to 2.5 wt%, preferably 0.5 to 2.5 wt%, more preferably 1.0 to 1.5 wt%; the content of component d is 0 to 2.5 wt%, preferably 0.5 to 2.5 wt%, more preferably 0.5 to 1.0 wt%, and the balance is a carrier.

3. The gas adsorbent according to claim 1 or 2,

the carrier is a polar carrier, preferably silica and/or alumina; and/or the presence of a gas in the gas,

the porous material is mesoporous carbon; and/or the presence of a gas in the gas,

the group VIII metal is selected from one or more of nickel, palladium and platinum, preferably palladium and/or nickel; and/or the presence of a gas in the gas,

the group IVB metal oxide is selected from titanium dioxide and/or zirconium oxide; and/or the presence of a gas in the gas,

the group VB metal oxide vanadium pentoxide; and/or the presence of a gas in the gas,

the group VIB metal oxide chromium oxide; and/or the presence of a gas in the gas,

the group IA metal salt is a sodium salt and/or a potassium salt, preferably a sulfate and/or nitrate salt of a group IA metal.

4. The gas adsorbent according to any one of claims 1 to 3, wherein the gas adsorbent has a specific surface area of 200-500m²Per g, pore volume of 0.5-1.0cm³/g。

5. The method for producing a gas adsorbent according to any one of claims 1 to 4, comprising:

mixing a precursor of the component a, a precursor solution of the component b, an optional precursor solution of the component c and an optional component d with a carrier to obtain a mixture, then removing liquid in the mixture, and calcining the obtained solid under an inert atmosphere to obtain the adsorbent.

6. The method of manufacturing according to claim 5, comprising:

step S1, dispersing the carrier in water to obtain carrier impregnation liquid, and mixing the precursor of the component a and the optional component d with the carrier impregnation liquid to obtain a first mixture;

step S2, mixing the first mixture with a precursor solution of component b and optionally a precursor solution of component c to obtain a raw material mixture;

and step S3, removing the liquid in the raw material mixture, and calcining the obtained solid in an inert atmosphere to obtain the adsorbent.

7. The method of claim 6, wherein in step S2, the mixture is prepared by adding a precursor solution of component b to the first mixture, and then optionally adding a precursor solution of component c.

8. The method as claimed in any one of claims 5 to 7, wherein the calcination temperature is 800-1000 ℃.

9. Use of the gas adsorbent of any one of claims 1-4 and the gas adsorbent produced by the method of any one of claims 5-8 for separating ethylene and/or acetylene.

10. Use according to claim 9, wherein the gas adsorbent is used for determining the content of ethylene and/or acetylene, preferably for simultaneously determining the ethylene and acetylene content in a temperature programmed surface reaction, preferably the use comprises:

placing the gas adsorbent in an adsorbent sample tube, placing the adsorbent sample tube between a TCD detector and a catalyst sample tube, connecting the adsorbent sample tube with a temperature programming system, and controlling the temperature of the adsorbent sample tube with a temperature control system;

in the process of carrying out the temperature programmed surface reaction, carrying out 3 times of temperature programmed experiments, wherein the temperature in the adsorbent sample tube in the 3 times of temperature programmed experiments is respectively 100-150 ℃, 40-80 ℃ and-40-0 ℃, and measuring the content of the product in the temperature programmed surface in the 3 times of temperature programmed experiments.

Technical Field

The invention belongs to the technical field of gas adsorption determination, and relates to a gas adsorbent and a preparation method and application thereof.

Background

Light olefins are an important basic organic chemical feedstock, previously relying on petroleum cracking. Under the influence of price and environmental factors, various countries are constantly developing new routes for olefin production. The methane oxidative coupling technology (OCM) uses natural gas to replace petroleum as a raw material, and provides a new way for preparing low-carbon olefin. The methane coupling reaction is that methane and oxygen generate ethylene and acetylene under the condition of a catalyst. The methane coupling reaction is a heterogeneous catalysis process, the activity, selectivity and reaction mechanism of the catalyst can be researched by a temperature programming technology, and the method plays an important role in the research and improvement of the catalyst. An important test data in the temperature programming technology is the determination of the contents of ethylene and acetylene in the products during the temperature programming process. The determination of the contents of ethylene and acetylene has important significance for the research and improvement of the performance of the catalyst.

At present, detectors commonly used for quantitative analysis in temperature programmed reactions include Thermal Conductivity Detectors (TCD), mass spectrometry detectors, infrared detectors, chemiluminescence detectors (CLD), Flame Ionization Detectors (FID), and the like. The thermal conductivity detector has high sensitivity and good quantitative effect, can detect almost all components but cannot distinguish various substances. The quantitative effect of the mass spectrometric detector is general and the mass numbers (m/z) of ethylene and acetylene cannot be clearly distinguished. The infrared detector has a common quantitative effect, and because the volume of the infrared cell is generally large, a long time lag exists during signal collection, which is not beneficial to measurement. In addition, chemiluminescence detectors (CLD), Flame Ion Detectors (FID) also cannot distinguish between ethylene and acetylene.

Therefore, how to quantify ethylene and acetylene is a problem to be solved by those skilled in the art. The inventor intensively studied and found that if an adsorbent is added before the TCD is used for detecting ethylene and acetylene signals, the adsorption and desorption of ethylene and acetylene are controlled by temperature, and then the content of ethylene and acetylene can be calculated by a difference method, the problems can be well solved.

However, there is no adsorbent in the prior art that can achieve the above object. Ethylene and acetylene adsorbents are reported in the prior art, and the single ethylene adsorbent is widely used, for example, activated potassium permanganate balls are produced in a large amount in an industrial mode. An acetylene adsorbent alone has also been reported, and for example, publication No. CN201380031200.7 "storage and stabilization of acetylene" discloses a carbon adsorbent for acetylene adsorption storage, and further publication No. CN201210579241.7 "metal-organic framework material for acetylene adsorption and storage and preparation method thereof" discloses a metal-organic framework material for acetylene adsorption storage. In the separation technique of ethylene and acetylene, Pore chemistry and size control in porous material capture from ethylene (Science, 2016,353(6295):141-144) reports that a mixed gas is introduced into an adsorption column at a certain flow rate, and acetylene is completely adsorbed to obtain high-purity ethylene. However, an adsorbent capable of simultaneously adsorbing and desorbing ethylene and acetylene has not been reported, and the prior art does not relate to the introduction of simultaneously measuring the contents of ethylene and acetylene in the temperature programming process.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a gas adsorbent, which can realize the complete adsorption of ethylene and acetylene, the complete adsorption of ethylene and acetylene by desorption of ethylene and the complete desorption of ethylene and acetylene by controlling the temperature. The method can be used for simultaneously measuring the contents of ethylene and acetylene in the temperature programmed surface reaction.

According to a first aspect of the present invention there is provided a gas sorbent comprising a carrier and an active component, the active component comprising one or more of the following components:

component a, which is a porous material;

a component b which is a group VIII metal or an oxide thereof;

optionally, component c, which is one or more of a group IVB metal oxide, a group VB metal oxide, and a group VIB metal oxide;

optionally, component d, which is a group IA metal salt.

According to a preferred embodiment of the invention, the gas adsorbent contains component a in an amount of 0.5 to 3.0 wt.%, e.g. 0.5 wt.%, 1.0 wt.%, 1.5 wt.%, 2.0 wt.%, 2.5 wt.%, 3.0 wt.% and any value in between, preferably 1.5 to 2.0 wt.%, based on the total mass of the gas adsorbent; the amount of component b is 0.5 to 3.0 wt%, e.g., 0.5 wt%, 1.0 wt%, 1.5 wt%, 2.0 wt%, 2.5 wt%, 3.0 wt% and any value therebetween, preferably 1.0 to 1.5 wt%; the amount of component c is 0 to 2.5 wt%, e.g., 0 wt%, 0.5 wt%, 1.0 wt%, 1.5 wt%, 2.0 wt%, 2.5 wt% and any value therebetween, preferably 0.5 to 2.5 wt%, more preferably 1.0 to 1.5 wt%; the amount of component d is 0 to 2.5 wt%, e.g., 0 wt%, 0.5 wt%, 1.0 wt%, 1.5 wt%, 2.0 wt%, 2.5 wt% and any value therebetween, preferably 0.5 to 2.5 wt%, more preferably 0.5 to 1.0 wt%, with the balance being carrier.

According to a preferred embodiment of the invention, the support is a polar support, preferably silica and/or alumina.

According to a preferred embodiment of the invention, the porous material is mesoporous carbon. The mesoporous carbon is a novel non-silicon-based mesoporous material, has the pore diameter of less than 50nm and larger specific surface area and pore volume when the pore diameter is less than 2 nm.

According to a preferred embodiment of the invention, the group VIII metal is selected from one or more of nickel, palladium and platinum, preferably palladium and/or nickel.

According to a preferred embodiment of the invention, the group IVB metal oxide is selected from titanium dioxide and/or zirconium oxide. Preferably titanium dioxide.

According to a preferred embodiment of the present invention, the group VB metal oxide is vanadium pentoxide.

According to a preferred embodiment of the invention, the group VIB metal oxide is chromium oxide.

According to a preferred embodiment of the invention, the group IA metal salt is a sodium and/or potassium salt, preferably a sulphate and/or nitrate salt of a group IA metal. For example, the group IA metal salt may be selected from one or more of sodium sulfate, potassium sulfate, sodium nitrate and potassium nitrate.

According to a preferred embodiment of the present invention, the gas sorbent comprises a carrier and active components comprising component a, component b, component c and component d. Preferably, the carrier is silicon dioxide and/or aluminum oxide, the component a is mesoporous carbon, the component b is palladium and/or nickel and oxides thereof, the component c is titanium dioxide and/or vanadium pentoxide, and the component d is one or more selected from sodium sulfate, potassium sulfate, sodium nitrate and potassium nitrate.

According to a preferred embodiment of the present invention, the gas sorbent comprises a carrier and active components comprising component a, component b, component c and component d. Preferably, the carrier is contained in an amount of 90.0 to 98.0 wt%, the component a is contained in an amount of 0.5 to 3.0 wt%, the component b is contained in an amount of 0.5 to 3.0 wt%, the component c is contained in an amount of 0.5 to 2.5 wt%, and the component d is contained in an amount of 0.5 to 2.5 wt%, based on the total mass of the gas adsorbent.

According to a preferred embodiment of the present invention, the gas sorbent comprises a carrier and active components comprising component a, component b, component c and component d. The gas adsorbent comprises 94.0-96.0 wt% of carrier, 1.5-2.0 wt% of component a, 1.0-1.5 wt% of component b, 1.0-1.5 wt% of component c and 0.5-1.0 wt% of component d, based on the total mass of the gas adsorbent.

According to a preferred embodiment of the present invention, the specific surface area of the gas adsorbent is 200-500m²G, preferably 300-400m²(ii)/g; the pore volume is 0.5-1.0cm³In g, preferably from 0.6 to 0.8cm³(ii) in terms of/g. In the present invention, the specific surface area refers to a specific surface measured by a BET methodAnd the pore volume is measured by a single-point method.

According to a preferred embodiment of the invention, the gas adsorbent is an ethylene and acetylene adsorbent.

According to a preferred embodiment of the present invention, the gas adsorbent completely adsorbs ethylene and acetylene at-40 to 0 ℃; completely adsorbing acetylene but not ethylene at 40-80 ℃; the ethylene and the acetylene are not adsorbed under the conditions of 100 ℃ and 150 ℃.

According to another aspect of the present invention, there is also provided a method for preparing the gas adsorbent, comprising:

mixing one or more of a precursor of the component a, a precursor solution of the component b, a precursor solution of the optional component c, the component b and the optional component d with a carrier to obtain a mixture, then removing liquid in the mixture, and calcining the obtained solid under an inert atmosphere to obtain the adsorbent.

According to a preferred embodiment of the present invention, the method for preparing the gas adsorbent comprises:

step S1, dispersing the carrier in water to obtain carrier impregnation liquid, and mixing the precursor of the component a and the optional component d with the carrier impregnation liquid to obtain a first mixture;

step S2, mixing the first mixture with a precursor solution of component b and optionally a precursor solution of component c to obtain a raw material mixture; preferably, the first mixture is mixed with the precursor solution of the component b, and then is mixed with the precursor solution of the component c; the preferred mixing mode is that the precursor solution of the component b is added into the first mixture, and then the precursor solution of the component c is added;

and step S3, removing liquid in the raw material mixture, and calcining the obtained solid in an inert atmosphere to obtain the adsorbent.

According to a preferred embodiment of the present invention, the removal of the liquid from the mixture may be carried out by methods conventional in the art, such as by removing the liquid by drying, for example, at 80-110 deg.C for 8-48 h.

According to a preferred embodiment of the invention, the mixing is carried out under conditions such as mixing at 40-60 ℃ for 4-12h to ensure adequate contact between the components.

According to a preferred embodiment of the present invention, the calcination temperature is 800-1000 ℃.

According to a preferred embodiment of the invention, the gas sorbent comprises a carrier and an active component comprising or consisting of:

component a, which is a porous material;

a component b which is a group VIII metal or an oxide thereof;

a component c which is one or more of a group IVB metal oxide, a group VB metal oxide and a group VIB metal oxide;

component d which is a group IA metal salt.

The preparation method comprises the following steps:

step S1, dispersing a carrier in water to obtain carrier impregnation liquid, and mixing a precursor of the component a and the component d with the carrier impregnation liquid to obtain a first mixture;

step S2, mixing the first mixture with a precursor solution of the component b to obtain a second mixture; preferably, the mixing is performed by adding the precursor solution of component b into the first mixture, more preferably, slowly dripping the precursor solution of component b into the first mixture, and preferably, the first mixture is kept in a stirring state during the mixing;

step S3, mixing the second mixture with a precursor solution of the component c to obtain a raw material mixture; preferably, the mixing is performed by adding the precursor solution of the component c into the second mixture, more preferably, slowly dripping the precursor solution of the component c into the second mixture, and preferably, the second mixture is kept in a stirring state during the mixing;

and step S3, removing the liquid in the raw material mixture, and calcining the obtained solid in an inert atmosphere to obtain the adsorbent.

According to a preferred embodiment of the present invention, the calcination temperature is 800-1000 ℃.

According to a preferred embodiment of the present invention, the component a precursor, the component b precursor, and the component c precursor are compounds capable of containing the above-described component a, component b, and component c in the adsorbent, respectively. For example, when the component a is mesoporous carbon, the precursor of the component a is a carbon source, preferably one or more selected from sucrose, glucose and fructose. Preferably, when adding the carbon source, it is advantageous to add an amount of acid, such as sulfuric acid, which facilitates carbonization of the carbon source. For another example, when the group IVB metal oxide is titanium dioxide, the precursor thereof may be tetrabutyl titanate. For another example, when the group VIII metal is palladium, the precursor of the group VIII metal or its oxide may be palladium nitrate.

According to a preferred embodiment of the present invention, the method for preparing the gas adsorbent comprises:

step I, dipping a carrier in water, adding a carbon source and sulfuric acid into the water, then adding group IA metal salt into the water, and uniformly stirring the mixture at a temperature of between 4 and 60 ℃ to obtain a first solution;

II, dissolving a precursor of the VIII group metal or the oxide thereof to obtain a second solution;

step III, adding the second solution into the first solution to obtain a third solution; preferably, the second solution is dropwise added into the first solution under the stirring state to obtain a third solution;

step IV, dissolving the precursor of the component c to obtain a fourth solution;

step V, adding the fourth solution into the third solution to obtain a fifth solution; preferably, the fourth solution is dropwise added into the third solution under the stirring state to obtain a fifth solution;

and VI, removing the liquid in the fifth solution to obtain a solid, and calcining the solid to obtain the gas adsorbent.

According to a preferred embodiment of the present invention, the sequence of steps I to VI may not be performed completely in the above-mentioned order, and steps I, II and the sequence for preparing the first solution and the second solution may be interchanged, or steps I and II may be performed simultaneously, and step IV for preparing the fourth solution may be performed before step III.

According to a preferred embodiment of the present invention, the method for preparing the gas adsorbent comprises:

step i, soaking silicon dioxide in water, adding sucrose and sulfuric acid into the water, then adding sodium sulfate or potassium sulfate into the water, and uniformly stirring the mixture at the temperature of 4-60 ℃ to obtain a solution A;

step ii, dissolving palladium nitrate in dilute nitric acid to form a palladium nitrate solution, and marking the obtained solution as a solution B;

step iii, keeping the solution A in a stirring state, and slowly dripping the solution B into the solution A to obtain a solution C;

step iv, slowly dripping tetrabutyl titanate into absolute ethyl alcohol, and uniformly stirring to obtain a solution D;

step v, keeping the solution C in a stirring state, slowly dripping the solution D into the solution C, and marking the obtained solution as a solution E;

step vi, stirring the solution E at 40-60 ℃ for 4-12h, putting the solution E into an oven at 80-110 ℃ and keeping the temperature for 8-48h to obtain a solid F;

and vii, putting the solid F into a tube furnace, and uniformly heating to 800-1000 ℃ under the protection of inert gas for calcination. The gas adsorbent (carrier is silicon dioxide, and active ingredients are mesoporous carbon, palladium, titanium dioxide, sodium sulfate or potassium sulfate) is obtained.

According to another aspect of the invention, the gas adsorbent and the application of the gas adsorbent prepared by the method in the separation of ethylene and/or acetylene are also provided.

According to a preferred embodiment of the invention, the gas adsorbent is used for determining the content of ethylene and/or acetylene.

According to a more preferred embodiment of the present invention, the gas adsorbent is used for simultaneous determination of ethylene and acetylene content in a temperature programmed surface reaction, preferably the application comprises:

placing the gas adsorbent in an adsorbent sample tube, placing the adsorbent sample tube between a TCD detector and a catalyst sample tube, connecting the adsorbent sample tube with a temperature programming system, and controlling the temperature of the adsorbent sample tube with a temperature control system;

in the process of carrying out the temperature programmed surface reaction, 3 times of temperature programmed experiments are carried out, the temperature in the adsorbent sample tube in the 3 times of temperature programmed experiments is respectively 100-150 ℃, 40-80 ℃ and-40 ℃ -0 ℃, and the temperature-programmed surface reaction curve is measured in the 3 times of temperature programmed experiments.

According to another aspect of the invention, the gas adsorbent and the application of the gas adsorbent prepared by the method in the performance research of the adsorbent are also provided.

In the present invention, the term "optionally" means the presence or absence thereof, which may be optionally added or not added as required.

Any numerical value mentioned in this specification, if there is only a two unit interval between any lowest value and any highest value, includes all values from the lowest value to the highest value incremented by one unit at a time. For example, if it is stated that the amount of a component, or a value of a process variable such as temperature, pressure, time, etc., is 40 to 80, it is meant in this specification that values 41 to 79, 42 to 78 … …, and 59 to 61, and 60 to 61, etc., are specifically enumerated. For non-integer values, units of 0.1, 0.01, 0.001, or 0.0001 may be considered as appropriate. These are only some specifically named examples. In a similar manner, all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be disclosed in this application.

The invention provides a gas adsorbent which can be used for measuring the contents of ethylene and acetylene in the process of temperature programming, and has the advantages of simple components, easy acquisition, low cost, simple preparation process, easily obtained raw materials and low production cost. The adsorption and desorption of the adsorbent to ethylene and acetylene can be realized by controlling the temperature, and then the contents of ethylene and acetylene are calculated by a difference method.

Drawings

FIG. 1 is a gas adsorption isotherm of the gas adsorbent produced in example 1 at 120 ℃.

FIG. 2 is a gas adsorption isotherm of the gas adsorbent produced in example 1 at 70 ℃.

FIG. 3 is a gas adsorption isotherm of the gas adsorbent prepared in example 1 at-20 ℃.

FIG. 4 is a gas adsorption isotherm of the gas adsorbent prepared in example 2 at 120 ℃.

FIG. 5 is a gas adsorption isotherm of the gas adsorbent prepared in example 2 at 70 ℃.

FIG. 6 is a gas adsorption isotherm of the gas adsorbent prepared in example 2 at-20 ℃.

FIG. 7 is a gas adsorption isotherm of the gas adsorbent produced in example 3 at 120 ℃.

FIG. 8 is a gas adsorption isotherm of the gas adsorbent produced in example 3 at 70 ℃.

FIG. 9 is a gas adsorption isotherm of the gas adsorbent prepared in example 3 at-20 ℃.

FIG. 10 is a gas adsorption isotherm of the gas adsorbent produced in example 4 at 120 ℃.

FIG. 11 is a gas adsorption isotherm of the gas adsorbent produced in example 4 at 70 ℃.

FIG. 12 is a gas adsorption isotherm of the gas adsorbent prepared in example 4 at-20 ℃.

FIG. 13 is a gas adsorption isotherm of the gas adsorbent produced in example 5 at 120 ℃.

FIG. 14 is a gas adsorption isotherm of the gas adsorbent produced in example 5 at 70 ℃.

FIG. 15 is a gas adsorption isotherm of the gas adsorbent prepared in example 5 at-20 ℃.

FIG. 16 is a temperature programmed surface reaction curve in example 6.

Detailed Description

The present invention will be described in detail with reference to examples, but the present invention is not limited to the examples.