CN102658085A - Adsorbing agent for capturing CO2 in flue gas, and preparation method thereof - Google Patents

Abstract

The invention belongs to the field of flue gas purification technology, and particularly relates to an adsorbing agent for separating CO2 in the flue gas, and a preparation method of the adsorbing agent. The adsorbing agent comprises a carrier, an active component and an auxiliary agent, wherein the carrier is one or more of coke, activated carbon, carbon fiber (CMS), charcoal and carbon-containing solid material; the active component is one or more of monoethanolamine, diethanolamine, tetraethylenepentamine and pentaethylenehexamine; and the auxiliary agent is one or more of K2CO3 and carbon nano tubes (CNTs). The preparation method of the adsorbing agent comprises the steps of: soaking, filtering, drying in the hydrogen environment and the like. The adsorbing agent has the characteristics of hydrophilicity, high adsorption capacity for CO2 under the low-pressure condition, low nitrogen adsorption capacity, easiness in desorption, simple preparation technology, low production cost and the like.

Description

A kind of benefit obtains CO in the flue gas 2Adsorbent and preparation method thereof

Technical field

The invention belongs to the flue gases purification field, particularly CO in a kind of minute separable flue gas ₂Adsorbent and preparation method thereof.

Background technology

Carbon dioxide is main greenhouse gases, is to cause global climate to become dim one of the main reasons.The energy supply of China is main with fire coal still at present, and wherein 80% is used for industries such as thermoelectricity, metallurgy, building materials.Along with " Kyoto Protocol " and " the back Kyoto Protocol " put into effect; China responds actively climate and changes and the reduction of greenhouse gas discharge problem; The Eleventh Five-Year Plan period discharging greenhouse gases control as national objective; Issued " China's reply climate changes national scheme " in 2007, clearly proposed the task of control carbon dioxide isothermal chamber gas discharging.

Present main CO ₂Capture separation method and mainly contain several types of absorption/absorption method, membrane separation process, flue gas recirculation firing method, change coal gasification combined cycle methods etc.; What employing was more in the industry is the amido chemical absorbent; Like monoethanolamine (MEA), diethanol amine (DEA), triethanolamine (TEA); Methyl diethanolamines (MEDA) etc., wherein monoethanolamine MEA is considered to optimum coal-fired flue-gas CO ₂Separate, its advantage be " molecular weight little, absorb the sour gas ability strong " to capturing after the burning CO of low concentration in the flue gas ₂Tool advantage; Its shortcoming is CO ₂Load-bearing capacity is low, and the equipment corrosion rate is high, and energy consumption was high when amine can be by other smoke components degradeds, absorbent regeneration, caused CO like this ₂Separation costs is high.

Adopt dry type to reclaim CO at present ₂Method, promptly special-purpose adsorbent carries out transformation absorption and reclaims the CO in the flue gas ₂Research is many, and corresponding adsorbent also has patent report, discloses a kind of carbon dioxide absorber like CN101543762A, comprises the active carbon of 100 weight portions and the amine substance of 10-60 weight portion, and this adsorbent is to dry state CO ₂Adsorbance is 16.8～49.5mg/g.CN101909743A discloses and has comprised solid material, the amine source is provided, said solid material is contacted on the surface with said solid material with said amine source adsorb amine molecule, so that absorption amine molecule and CO ₂The stream contact forms amine functional group, and increase can be used for capturing CO ₂Amine partly.CN101559348A discloses a kind of being used for from containing CH ₄And/or N ₂Gas in separation of C O ₂Adsorbent, get the Concave-convex clay rod raw material, pulverize, add acid solution, 60-90 ℃ of constant temperature modification handled, wash to pH value be 7, drying and roasting and getting.CN102343254A discloses a kind of normal temperature CO ₂The solid amine adsorbent, for through liquid organic amine modified carbon nanotube, wherein the important percentage composition of CNT is 50%～70%, the weight percentage of organic amine is 30%～50%, CO ₂Adsorption capacity reach more than the 2.45mmol/g.

Summary of the invention

First technical problem to be solved by this invention provides a kind of reproducible adsorbent.Alkaline-earth metal-amine complex the CO absorption of adsorbent dependence self porous and hole surface ₂, and under the low pressure condition with absorption CO ₂Desorb.

Second technical problem to be solved by this invention provides a kind of adsorbent.This adsorbent can effectively, optionally adsorb the CO in the gas-flow ₂, the CO of absorption ₂Quality accounts for 10～30% of adsorbent mass, and can adsorb a spot of sulfide and oxynitrides.

The 3rd technical problem to be solved by this invention provides a kind of adsorbent.This adsorbent possess hydrophilic property, be a kind of be main Large ratio surface adsorbent with the mesopore.

The 4th technical problem to be solved by this invention provides a kind of adsorbent.It is simple that this adsorbent prepares process, and production cost is low, and performance of the adsorbent is stable.

The present invention solves the problems of the technologies described above the technical scheme that is adopted:

A kind of benefit obtains CO in the flue gas ₂Adsorbent; Comprise carrier, active constituent and auxiliary agent; Carrier is one or more in coke, active carbon, charcoal fiber (CMS), charcoal, the carbonaceous solids material, and active component is one or more in monoethanolamine, diethanol amine, tetren, the penten, and auxiliary agent is K ₂CO ₃And in the CNT (CNTs) one or more, each component and mass percent thereof are in this adsorbent: carrier: 80.1～88.8%, and active constituent: 10.1～17.6%, auxiliary agent: 1.0～4.5%.

A kind of benefit obtains CO in the flue gas ₂Adsorbent and preparation method thereof: comprise the steps:

(1) select to carry this: take by weighing 8.0～10.0g active carbon, require activated carbon to burn the mistake rate: 50～70%, specific area＞800m ²/ g is main with mesopore;

(2) obtain solution: the deionized water of measuring 600～800ml with the graduated cylinder of 1000ml is poured in the beaker of 2000ml, adds 200～300ml monoethanolamine, takes by weighing K then ₂CO ₃: 35.2～39.2g, CNTs:3.8～7.6g, join in the beaker together, and beaker is put into water bath with thermostatic control, the control temperature is 65～75 ℃;

(3) dipping process: when treating that temperature in the beaker reaches 70 ℃, the carrier that takes by weighing in (1) is joined in the beaker, manually stir at interval and get final product, dip time is 1～2 hour;

(4) filtration drying: the active carbon after will flooding was put under the atmosphere of hydrogen condition under 110～130 ℃ of conditions dry 4～6 hours behind elimination solution, promptly got the product adsorbent;

Description of drawings

Fig. 1 be among the embodiment selected carrier to CO ₂Adsorpting data;

Fig. 2 is that embodiment 1～3 adsorbent is to CO ₂Adsorption curve, wherein Port1 is that embodiment 1 adsorbent is to CO ₂Adsorption curve, Port2 is that embodiment 2 adsorbents are to CO ₂Adsorption curve, Port3 is that embodiment 3 adsorbents are to CO ₂Adsorption curve;

Fig. 3 is that embodiment 1～3 adsorbent is to N ₂Adsorption curve, wherein Port1 is that embodiment 1 adsorbent is to N ₂Adsorption curve, Port2 is that embodiment 2 adsorbents are to N ₂Adsorption curve, Port3 is that embodiment 3 adsorbents are to N ₂Adsorption curve.

The specific embodiment

Below in conjunction with the specific embodiment the present invention is made further detailed description, but embodiment of the present invention is not limited only to following embodiment.

Embodiment 1

Take by weighing 8.0g active carbon AC302, be positioned in the drying basin, the deionized water of measuring 600ml with the graduated cylinder of 1000ml is poured in the beaker of 2000ml; Then beaker is put into water-bath, 75 ℃ of bath temperature controls are after 45 minutes; Deionized water temperature in the test beaker when the deionized water temperature reaches more than 65 ℃, adds the monoethanolamine 300ml that graduated cylinder is got; With the remaining monoethanolamine in a little washed with de-ionized water graduated cylinder, example is gone in the beaker; Take by weighing K ₂CO ₃: 35.2g, CNTs:3.8g, join together in the beaker, the fluid temperature in the control beaker is 65～75 ℃; Every carrier that stirred beaker bottom at a distance from 15～20 minutes with glass bar gently; 1.5 after hour; Separate carrier and solution in the beaker, the carrier of separating is packed into to be with to be added in the reaction tube of electric heater temperature control, and reaction tube temperature is controlled at 120 ℃; Feed the hydrogen of 99.99% (Vol) from the reaction tube upper end; Amounts of hydrogen is 120ml/min, and the marquis reduced to normal temperature with reaction tube temperature in 6 hours, and the activated carbon that takes out in the reaction tube promptly gets the product adsorbent;

Each component and mass percent thereof are in the adsorbent of present embodiment preparation: activated carbon: 80.1%, and active constituent (amido complex compound): 17.6%, auxiliary agent (CNT and alkaline earth oxide): 2.3%.

Embodiment 2

Take by weighing 8.7g active carbon AC302, be positioned in the drying basin, the deionized water of measuring 800ml with the graduated cylinder of 1000ml is poured in the beaker of 2000ml; Then beaker is put into water-bath, 70 ℃ of bath temperature controls are after 45 minutes; Deionized water temperature in the test beaker when the deionized water temperature reaches more than 65 ℃, adds the monoethanolamine 200ml that graduated cylinder is got; With the remaining monoethanolamine in a little washed with de-ionized water graduated cylinder, example is gone in the beaker; Take by weighing K ₂CO ₃: 46.4g, CNTs:5.6g, join together in the beaker, the fluid temperature in the control beaker is 65～70 ℃; Every carrier that stirred beaker bottom at a distance from 15～20 minutes with glass bar gently; 1.5 after hour; Separate carrier and solution in the beaker, the carrier of separating is packed into to be with to be added in the reaction tube of electric heater temperature control, and reaction tube temperature is controlled at 110 ℃; Feed the hydrogen of 99.99% (Vol) from the reaction tube upper end; Amounts of hydrogen is 120ml/min, and the marquis reduced to normal temperature with reaction tube temperature in 6 hours, and the activated carbon that takes out in the reaction tube promptly gets the product adsorbent;

Each component and mass percent thereof are in the adsorbent of present embodiment preparation: activated carbon: 85.3%, and active constituent (amido complex compound): 10.2%, auxiliary agent (CNT and alkaline earth oxide): 4.5%.

Embodiment 3

Take by weighing 9.9g active carbon AC302, be positioned in the drying basin, the deionized water of measuring 800ml with the graduated cylinder of 1000ml is poured in the beaker of 2000ml; Then beaker is put into water-bath, 67 ℃ of bath temperature controls are after 45 minutes; Deionized water temperature in the test beaker when the deionized water temperature reaches more than 65 ℃, adds the monoethanolamine 220ml that graduated cylinder is got; With the remaining monoethanolamine in a little washed with de-ionized water graduated cylinder, example is gone in the beaker; Take by weighing K ₂CO ₃: 39.2g, CNTs:7.6g, join together in the beaker, the fluid temperature in the control beaker is 65～67 ℃; Every carrier that stirred beaker bottom at a distance from 15～20 minutes with glass bar gently; 1.5 after hour; Separate carrier and solution in the beaker, the carrier of separating is packed into to be with to be added in the reaction tube of electric heater temperature control, and reaction tube temperature is controlled at 110 ℃; Feed the hydrogen of 99.99% (Vol) from the reaction tube upper end; Amounts of hydrogen is 120ml/min, and the marquis reduced to normal temperature with reaction tube temperature in 6 hours, and the activated carbon that takes out in the reaction tube promptly gets the product adsorbent;

Each component and mass percent thereof are in the adsorbent of present embodiment preparation: activated carbon: 88.8%, and active constituent (amido complex compound): 10.1%, auxiliary agent (CNT and alkaline earth oxide): 1.1%.

Claims (4)

1. a benefit obtains CO in the flue gas ₂Adsorbent; Comprise carrier, active constituent and auxiliary agent; It is characterized in that: said carrier is one or more in coke, active carbon, charcoal fiber (CMS), charcoal, the carbonaceous solids material; Active component is one or more in monoethanolamine, diethanol amine, tetren, the penten, and auxiliary agent is K ₂CO ₃And in the CNT (CNTs) one or more, each component and mass percent thereof are in this adsorbent: carrier: 80.1～88.8%, and active constituent: 10.1～17.6%, auxiliary agent: 1.0～4.5%.

2. carrier according to claim 1 is preferentially selected active carbon, charcoal fiber for use.

3. active constituent according to claim 1 is preferentially selected monoethanolamine, diethanol amine for use.

4. a benefit obtains CO in the flue gas ₂Adsorbent and preparation method thereof: comprise the steps:

(1) select to carry this: take by weighing 8.0～10.0g active carbon, require activated carbon to burn the mistake rate: 50～70%, specific area＞800m ²/ g is main with mesopore;

(2) obtain solution: the deionized water of measuring 600～800ml with the graduated cylinder of 1000ml is poured in the beaker of 2000ml, adds 200～300ml monoethanolamine, takes by weighing K then ₂CO ₃: 35.2～39.2g, CNTs:3.8～7.6g, join in the beaker together, and beaker is put into water bath with thermostatic control, the control temperature is 65～75 ℃;

(3) dipping process: when treating that temperature in the beaker reaches 70 ℃, the carrier that takes by weighing in (1) is joined in the beaker, manually stir at interval and get final product, dip time is 1～2 hour;

(4) filtration drying: the active carbon after will flooding was put under the atmosphere of hydrogen condition under 110～130 ℃ of conditions dry 4～6 hours behind elimination solution, promptly got the product adsorbent.

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