JPS62105912A - Gaseous carbon dioxide adsorbing porous resin - Google Patents

Abstract

PURPOSE:To develop a solid amine based repeatedly usable CO2 gas adsorbing porous resin having improved adsorptivity, by subjecting porous polymer particles obtained by polymerizing divinylbenzene with glycidyl methacrylate to addition reaction of a polyfunctional amine. CONSTITUTION:A CO2 adsorbing porous resin, obtained by mixing divinylbenzene (DVB) with glycidyl methacrylate (GMA) at 7:93-65:35 weight ratio, adding 60-230pts.wt., based on 100pts.wt. total of the DVB and GMA, 4-methyl-2- pentanol as a precipitant to the resultant mixture, suspension polymerizing the mixture in water to form fine primary polymer particles having <=1mum diameter, converting the primary articles into an aggregate to form a microreticular type porous polymer, subjecting the polymer to addition reaction of a polyfunctional amine, e.g. polyethyleneimine having <=10,000 molecular weight to form an amine adduct porous polymer and washing the polymer with water, hot water and methanol to remove the precipitant and residual polyfunctional amine and having improved adsorptivity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a solid amine-based porous carbon dioxide adsorbing resin that has excellent adsorption properties and can be used repeatedly.

[Prior art and its problems] When humans live for long periods of time in closed spaces such as submarines and space bases, it is possible to maintain a constant concentration of carbon dioxide by removing carbon dioxide using an appropriate adsorbent. It is necessary to maintain the following.

For example, adsorption of carbon dioxide gas on submarines is carried out by using an aqueous monoethanolamine solution, showering the amine solution from the top of an adsorption tower filled with stainless steel wool, and blowing air containing carbon dioxide from the bottom of the adsorption tower. In order to desorb carbon dioxide from the amine liquid that has been sucked up with carbon reformed gas, it is possible to release the carbon dioxide gas by stirring the amine i and recycle the remaining amine liquid. ．． No
.

4, pp. 227-233 <'1983).

In addition, in recent years, the United States (Mamoro/v
It is becoming popular in Japan as well, and national projects 1~
There are also plans to build a space base in the future.

However, unlike on Earth, the environment in space is zero gravity and under high vacuum, which imposes various restrictions on the carbon dioxide adsorbents used there.

Specifically, it is difficult to use liquid amine-based adsorbents because they do not maintain a constant shape under zero gravity.
In a vacuum, it vaporizes and becomes a harmful gas, which not only corrodes various equipment but also threatens the health of people living on the space base.

In addition, the adsorbed carbon dioxide gas is used to grow algae, etc.
Since it is assumed that carbon dioxide will be recycled as oxygen through carbon dioxide assimilation, adsorbents used in the space environment must at least be solid, easily adsorbed and desorbed, and suitable for repeated use. ing. However, alkali metal hydroxides such as lithium hydroxide, which have been conventionally used as solid adsorbents, require high temperatures to desorb carbon dioxide gas, making them unsuitable for repeated use and lacking in practicality.

[Means for Solving the Problem] In view of the above-mentioned current situation, the present inventors have developed a material that has excellent carbon dioxide adsorption properties and that is
The present invention was completed as a result of intensive research to develop a solid amine adsorbent that can be used repeatedly in outer space.

That is, the carbon dioxide adsorbing porous resin of the present invention is made of porous polymer particles obtained by polymerizing divinylbenzene (hereinafter referred to as DVB) and glycidyl methacrylate-1 to (hereinafter referred to as GMA). It is characterized by being formed by adding a polyvalent amine to the above.

The porous polymer that can be used in the present invention is prepared by adding a precipitant to a monomer mixture of DVB and GMA, polymerizing it in suspension in water, washing the resulting polymer particles first with water, then with methanol, and then washing the resulting polymer particles with water and then methanol. It can be obtained by performing Soxhlet extraction with acetone until the M is constant and removing the precipitant and hexamer remaining in the particles.

The term precipitant used in the present invention refers to a "solvent that is completely compatible with nanatsumer but has no affinity for the polymer produced by polymerization," and in the presence of the solvent, nanatsumer Suspension polymerization produces soft, fine polymer particles, most of which are 1 μm or less in diameter, which become aggregates and form porous resins generally called macroreticular type (hereinafter referred to as MR type) porous resins. form a polymer.

The ratio of DVB/GMΔ in the porous polymer is G
As the amount of MA increases, the glycidyl group content of the resulting porous particles increases, which is advantageous for addition reaction with polyvalent amine in the next step, but as DVBffi decreases, the specific surface area decreases, resulting in weight gain. When DVB/GMA=6/94, an MR type porous structure is not substantially formed. Therefore, in the present invention, DVB (weight%)/GMA (weight%)
)=7-65/93-35 is preferable, 9-45
/91-55 is particularly preferable, 10-35/90-65
is most preferred.

Note that DVB is not supplied in pure (high purity) form, but rather as industrial DVB (about 55% pure), which is a mixture of ethylvinylbenzene and various other saturated compounds.
These industrial D
VB can also be preferably used in the present invention.

When making the above DVB/GMA porous polymer porous, aliphatic hydrocarbons such as 2,2,4-trimethylpentane, phthalic acid dialkyl esters such as dioctyl phthalate (however, esters of higher alcohols of octyl or higher) are used. ) can be used as the precipitant, but when these precipitants are used, cracks or crusting (the degree of porosity on the surface compared to the inside of the particle) may occur on the surface of the generated particles. is inferior, and in severe cases, the surface has a total < 4
Surface defects such as 1il+ holes (so-called a skin-covered state) may occur, leading to weakening of the grains and a reduction in the effective surface area.

In the present invention, a precipitant that can be preferably used is 4-methyl-2-pentanol (hereinafter referred to as MIBG), and this MIB (,I; ball, 1]VB/GM
It is particularly useful as a precipitant in this system because porous grains with no surface defects can be obtained regardless of the heptamer ratio of A.

The amount of the precipitant added (preferably 60 to 230,000 ml parts per 100 parts of the monomer mixture of DVB/GM, A); if the amount added is less than 60 parts, the precipitation of the polymer will necessarily be incomplete. - No significant porosity occurs.

On the other hand, if it exceeds 230 parts by weight, the grains become porous or stiff and have only weak mechanical strength. Therefore, in the present invention, a particularly preferred addition hII is 9C)-1ε30.

The carbon dioxide-absorbing porous resin of the present invention (the glycidyl of the porous polymer particles described above is also subjected to an addition reaction with a polyvalent amine).Addition reaction of glycidyl groups and amine groups 65, general IJ progresses easily even at room temperature, as seen in two-component epoxy resin paints, but in the present invention, glycidyl groups are fixed in the polymerization phase of the chopsticksic polymer. Possibly because of the presence of diluents such as water and alcohol, the
If it heats up over time, it tends to be difficult to respond. For this reason,
In order to improve the affinity of the diluent with the polyvalent amine, the porous particles are directly immersed in the polyvalent amine and the addition reaction is carried out. (according to the instructions, 60~...1!') at O'C for 1 to 5 hours, then at 80'C for 5 hours ('I-C
tv optical spectroscopy h11 reaction can be achieved.

Polyvalent j that can be used in the above A' addition reaction (:43
7 min, te, J dylenediamine, di]-dilenetri) amine, + = Lee II dylenediamine, detraethylene pe], ・'lamin and (f penta■-thiylnonhekilymin'), etc. /N'7'Minii 1, (Shi, Nomedi, J Reami, / -jf [1 Pyramine, Dimethylamine 77th "''Ruamine, Diethylamine 7th B'ylamine, -Imi 5) Ji'Sufuro 1- propylamines, such as 1,2- or 1'3-diamine/butylamine,
diaminoalkanes such as pan, 1,4-diP'mi-2butane, a3 and ], 6-diami, no/\xane; Low-melting-point aromatic polyvalent amino acids, polyethynonimine, polyallylamine, and the like having various molecular weights can be used.

Among the various amines listed in 1.7, there are also low-molecular amines (which are highly bioactive and require special care in handling).
(tIJI'Hf;, '(＞If separation occurs during playback, etc.), it is very dangerous. However, the solid borylamine requires a diluent during the reaction, and the polymer ω grade of polyethyleneimine is extremely viscous and requires the addition of a diluent. 7
3 [1 or 1 is required.

Therefore, according to the invention, polyethyleneimine with a molecular weight of 10,000 or less is optimal.After the completion of the 14-addition reaction, the amine-attached 1311 porous raw 1,000-pound rods are first heated with water and then heated. Wash the cleaning solution with water until it no longer exhibits lukewarm properties, and then wash it with methanol and detergent. ! Q
The polyvalent amines that were not reacted with Agents J''3 and 7JI were completely removed, and the carbon dioxide adsorbent porous resin of the present invention was obtained (A).

[Function] According to the present invention, the porous resin used as a carbonic acid sludge adsorbent is in a solid state formed by attaching a polyvalent amine to the glycidyl group of a porous polymer particle. To the ladle (;t h
[1] The polyvalent amine adsorbs carbon dioxide gas well and has the effect of easily deboning the adsorbed carbon dioxide gas with a slight heat treatment.3 [Example] The present invention is described in the following example. A more detailed explanation will be given at 71'. d3, the composition of each component in the examples is expressed in 1,000 (-7 parts).

Porous polymer particles! 1 (Installation W installed in the cowl bath and] in the table below)
Shown in 1! , 2. Add the ion exchange mixture (1) to 100% of each formulation, and add the ion exchange solution (2) under stirring. 40~.-
160 rpm) Disperse the Na Cl at 1111,) and take it! [Form the water phase! Ta. This (K, D
−(I/?R compound of V F3 and G M A, M I
B G,, F3 P01 was added and the mixed and dissolved oil phase was heated to 1111°C under stirring, and the external temperature was increased from 60°C to 90'C.
The stomach was warmed in stages for 7 hours to cause a polymerization reaction. The polymer particles were filtered through a mesh sieve, washed first with water and then thoroughly with methanol, and then carefully subjected to Soxhlet extraction with a, setone. Refine the porous grains with a direct f\0.1.'r..., 0.4si culm degree,
Preparation mode: 80 to 90% yield for 1 /mer 1 -
Also. The specific surface area and glycidyl foundation ratio of each of the porous polymer particles obtained in the above were measured by the following methods, and the measurement results are shown in Table 1.

(1) Specific surface area: B using Shimadzu Micromeritics specific surface area automatic analyzer model 2000.

E and T were measured by the single point method and expressed as tail/3.

(2) Glycidyl group-containing m: Add 20d of 0°2N hydrochloric acid-dioxane solution to 0.5g of sample, photograph at 60°C for 1 hour, and then titrate with 0.5N sodium hydroxide aqueous solution using cresol red as an indicator. The glycidyl group content was calculated from the value and expressed as equivalent/sample 3.

Margin below (Note 1) DVB content approximately 5 amounts VB was used.

(Note 2) Penzoyl peroxide (Note 3) Polyvinyl alcohol (manufactured by Nippon Gosei Kagaku T Gyo Co., Ltd., Gohsenol GH-23) was used as a 6% aqueous solution.

Addition reaction of polyvalent amines Take 2.59 g of each of the porous polymers prepared above (No. 1-1 to 1-5) and put them into a 100 d Erlenmeyer flask 1.
Addition reaction was carried out by adding polyethyleneimine 109 having an average molecular weight of about 300 and boiling the system at 80"C for 5 hours.

After the completion of the addition reaction, the amine addition porous polymerization process is performed by first washing with water, then boiling water until the washing solution no longer shows alkalinity, then roughly washing with methanol, and then washing with boiling water.
It was purified by completely removing the unresolved polyvalent amine. The carbon dioxide adsorption amount of the carbon dioxide adsorbent porous resin thus obtained.

was measured by the following method, and the results are shown in Table 2.

(3) Carbon dioxide scum absorption 1111 measurement method: Sample approximately 207J
iff (precious H') 8 hot IJ take, iVj % buried two [
As a process, the nitrogen gas stream 1;, 100'C and the soil is heated and reduced for 53 minutes to remove various gases and water absorbed by the stones. Next, the heating was stopped and gas suction was carried out at room temperature under a stream of carbon dioxide gas. When the weight reaches a constant value, the amount of carbon dioxide gas adsorbed is calculated using the following formula.

Carbon dioxide adsorption amount (%) 1 square 11 weight M (9) As is clear from the results in the margin below, the polymer particles of Example No. 1-1 and GMA produced without mixing GMA at all
Example No. manufactured by mixing small stars.

In the polymer particles 1-2, the amount of glycidyl groups incorporated was extremely small, so the amount of added amine f was small, and only a small amount of carbon dioxide gas adsorption was obtained.

On the other hand, the polymer particles of Example No. 1-5 with a large amount of GMA mixed had a high content of glycidyl groups, but did not form porous particles, and as a result, the amount of carbon dioxide gas adsorbed was small.

In contrast, the polymer particles of Examples Nos. The 2'-4 resin showed extremely excellent carbon dioxide adsorption properties.

Moreover, regarding the amine-added resin of the above example No. 2-4,
The "pretreatment step of removing various gases and moisture at 100°C under a nitrogen gas flow" and the "step of adsorbing carbon dioxide until a constant weight is achieved" in A3 of the above (3) Carbon dioxide adsorption @ product measurement method '' was defined as one cycle, and the performance of adsorption and desorption was confirmed by repeating this cycle. As shown in the results in Table 3 below, the decrease in the amount of carbon dioxide adsorption was extremely small even after repeating the 1Q cycle. , which was excellent.

Table 3 [Effects of the invention] The carbon dioxide adsorbing porous resin of the present invention has DVB and GMA
It is made of porous polymer particles obtained by the polymerization of , and polyvalent amines added to the glycidyl groups contained in the particles, so it has excellent carbon dioxide adsorption properties and It is an extremely excellent solid amine-based carbon dioxide adsorbent, as its initial carbon dioxide adsorption properties do not deteriorate even after repeated gas adsorption and desorption.

Claims (1)

[Claims] 1. A carbon dioxide gas-adsorbing porous resin, which is produced by adding a polyvalent amine to particles of a porous polymer obtained by polymerizing divinylbenzene and glycidyl methacrylate.