JPS5939304A - Improvement in separation method of gaseous mixture using semipermeable membrane made of substituted poly(aryleneoxide) polymer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to gas separation. -Face odor
j1. The present invention relates to the separation of gas by the use of a semi-permeable membrane, and the present invention relates to the separation of gas by the use of a semi-permeable membrane made from at least seven kinds of poly(arylene oxide) polymers. It is about law.

The use of semipermeable forces to separate gas mixtures into their constituent parts (and at least a less concentrated fraction of the other constituents) has long been known.

The development of semipermeable membranes for this purpose was published in U.S. Patent No.
230. It is well and comprehensively described in No. 63, Section 6. In addition to the membranes described therein, the United States also 'e'F n'
s3.33θ, g4t4 and 3rd. g99.
Other membranes are available for this type of purpose, including those described in US Pat. Although most, if not all, of these membranes have been shown to be effective for other intended uses, none are completely satisfactory. Generally, the membranes used for this type of separation have one or more of the following desirable flux, selectivity, and lifetime characteristics.
There is a lack of two, so the industry continues to look for Betsuya's solution.

Of particular interest to the Chemical Flow Processing Industry are the hydrocarbons (typically natural scum) to carbon dioxide gas! hi (-!L fc, tt-J, ) ll4L water; (z
(1) It is a film that exhibits a high density #t<: xq and exhibits excellent characteristics against acid astringency from air. Commercially, these methods do not use membranes at all and use absorption techniques in the former and low temperature techniques in the latter. Both techniques are expensive and therefore expensive to operate. Therefore, different methods of identifying
Although there is a growing need to implement this process, methods using membrane technology currently appear to offer significant economic advantages.

However, there are currently no membranes that are fully suitable for testing any of the seven processes.

According to the invention, the 12 fractions K of the gas mixture containing at least one of carbon dioxide, oxygen, and hydrogen sulfide, i.e., the fractions enriched with at least one of carbon dioxide, oxygen, and hydrogen sulfide, and the Another method for separating these two components comprises using, as a separation vehicle, at least seven Yt-containing poly(arylene oxide) polymers containing at least about 30 mole percent of structural units of the following structural formula XR. This is improved by using a semipermeable membrane containing at least about % JSX, based on the total weight of JSX. However, each R1-L is independently hydrogen, an aliphatic, alicyclic, or aromatic group, or an inert substituted derivative thereof, each X is independently at least a chloro group, and a#' io or /. This method operates in substantially the same manner as known methods.

That is, a gas mixture is passed through a semipermeable membrane in such a way that a portion of the gas mixture selectively passes through the membrane, leaving the concentrated fraction on one side of the membrane and the dry fraction remaining on the other side of the membrane. bring into contact. This method, when configured in a well head, is particularly useful for the separation of carbon dioxide and hydrogen sulfide from natural gas streams, and for the production of enriched oxygen streams from air. Particularly with regard to the separation of carbon dioxide from methane and the separation of oxygen from nitrogen, this method exhibits excellent selectivity and selectivity. It is suitable for separating one or the other. The present invention is particularly useful for the separation of carbon dioxide S9 and/or hydrogen sulfide from natural gas and for the separation of oxygen from air. The ratio of the gases forming the sludge mixture k4ti...#'',L can be widely separated, and therefore the present invention can be applied to a wide variety of separated oils 111b.

The membrane used in the present invention is a 16-substituted poly(arylene oxide) polymer of at least /f'+4 containing structural units of the following structural formula: at least about 2! ; Contains M amount%. However, this is the same as defined on R, X, and aFi. D
Preferably, each R is independently a C, to C6 aliphatic (more preferably alkyl) group, a C, to C6 aliphatic (more preferably cycloalkyl) group, or an aryl (most preferably I') group. i phenyl) group, or an inert substituted derivative thereof. The "inert substitution" used in the present invention is
Selectivity characteristics (for its intended use) of the membrane containing the polymer in %: [*T#L substituents such as halogen, alkyl, nitro, alkoxy, etc. not reduced above one or more It means that it can be included.

Typical Rlk#'s include t, methyl, ethyl, n-propyl, improhil, butyl, tert-tin, cyclohegycyl, phenyl, tolyl, bromomethyl, and the like. Unexploded E! The term “independently” used in IJ is for each @:
F'J- means that the substituents can also be different in the structural units; for example, each R group can be methyl, or one can be methyl and the other ethyl.

The X group of structural formula (1) is at least partially sterically inhibited (
5teric 1nhibitors) and its bulkiness and/or polarity. "sterically inhibited" means that these groups tend to act as spacers for the mass of adjacent polymers.
It is possible that ξ may also perform other functions that increase the overall resistance of the film, but the full range of these functions is currently not fully understood. These groups are preferably at least the size of a bromo group. Typical examples of these groups are halogen (chloro, bromo, or acid iodo), azide, hydroxyl, thiol, ether, dioether, ester, thioester, phosphoric acid, its ester or salt, nitro, nitrate ester, nitrite. Groups such as ester, alkyl, aryl, acyl, thioacyl, etc. Among these groups, preferred are halogen groups,
A bromo group appears on IJ¥. - Formula (1
In the structural unit of ), the Kawahara preconditions other than those filled by #)f4 by the X group are filled by hydrogen atoms.

If used in the present invention, 俟poly()'rylene oxide) Jt-combined Ll can be a homopolymer 1 or co-merged, in the latter case at least about 5
θ mol %, preferably at least about 73 mol % of the formula (
Contains the structural unit of 1). When the polymer is a copolymer, the comonomer other than the unit of formula (1) is essentially any structural unit that can be copolymerized with the structural unit of formula (1), such as bisphenol A1 or bisphenol sulfone. You can also do it. Preferably, the direct conversion poly(
The arylene oxide) polymer consists essentially of structural units of formula (1), although each structural unit may contain the same substituents (eg, the same R or X groups). Cyclobrominated poly(,2,O-dimethyl-/,gouphenylene oxide) and waxed poly(,2,A-xylenol), also known as m,A-genated poly(xylylene oxide) or poly(,2,A-xylenol). , 2, dimethyl-p-phenylene oxide) is particularly preferred. Practical considerations such as economics, ease of membrane fabrication, etc. are the only important limitations on the molecular weight of these substituted poly(arylene oxide) N-conjugates.

The substituted poly(oxide) polymers used in the present invention are generally known, and many methods of making them are known in the art. For example, A,
S, Hey, Journal of Polymer Zaku 1 Huss 5
As taught in ``Polymerization by Oxidative Coupling,'' Volume 3, 3 g/page (7% 4 years), λ, O-xylenol is polymerized without polymerization, and then White, Orlando, Polyethers, As taught in Volume 7.2, Page 77g (19717) titled "Brominated poly(phenylene oxide), ■ Bromination of poly(',,2,O-dimethyl-/,Guphenylene oxide)" By brominating the above polymer under ionic conditions, brominated poly(,2,O-dimethyl-p-phenylene oxide) # can be easily produced. Many other substituted polyarylene oxide polymers described herein can be made by similar processes.

The semi-permeable membrane used in the present invention is compatible with a modified poly(arylene oxide) polymer consisting of at least a glue of @ modified poly(arylene oxide) N polymer containing the structural unit of the formula (11). Any compatible polymer can be used in membrane construction;
Typical polymers include poly(aryl sulfone), poly(phenylene sulfone), poly(maleic anhydride), and their individual copolymers. The molecular weight of this polymer can vary widely, but is usually in the 5θ% range of Ik m poly(arylene oxide) JR polymer 53M.
It is within i. Certain physical properties such as strength, durability, and deflection? To help with LJIQ, some blends of "Oki itself" may be desirable. Provided by substituted poly(arylene oxide) polymers
It is desirable to keep the incorporation of other polymers into the polymers to a minimum to avoid compromising their properties. Therefore, the substituted poly(arylene oxide) polymer preferably has at least about % of the membrane, preferably at least about 0%, preferably at least about It constitutes 73 folds, fA%.

The above-mentioned polymer is prepared by the following method used in the preparation of fiQ of flo. is 5
Form a ~70w 11' cold solution. Generally non-polar solvents are used: TQ, chloroform, toluene, chlorobenzenes (even t, t: o-dichlorobenzene),! An example is a hydrogenated hydrocarbon (for example, perchlorethylene). These non-natural compounds can be used in combination with polar solvents such as dimenalformamide, dimethyl sulfoxide, dimethylacetic acid amide, acetone, menalenalic acid, or can be combined with such combinations. Oh, and the non-Ihae bathing is at least about 50M (Saka%) of Kaji @ thing.
Configure 1'. When used in the production of bridge cutting (or other combinations), it is generally the same method used to prepare a substituted poly(arylene oxide) polymer solution.
of the above physical properties during melt cutting, 20*Q%, good i1. <h,
t~i0#=%bathn**9〈Two solutions or one or more solutions are mixed at room temperature. The irrigated solution is then poured onto a clean glass plate and spread evenly over the area with the aid of some kind of device, such as a doctor blade. The membrane is then wall-dried, removed from the glass plate, and placed in air under normal conditions for a suitable period of time.
Dry for at least 1 hour. , 'IM application and solvent evaporation (removal) occur simultaneously during the drying process. In other embodiments, these membranes can be prepared and manufactured by a variety of laboratory and commercial techniques known in the art. These materials can also be manufactured into materials other than films, such as hollow fibers. Furthermore, based on these 18 or Philleno (
It can be used in complex formulations such as coatings, products, etc.

The membranes used in the present invention can be manufactured to any desired thickness, but are approximately 2S mils (/milt; 1 = 2, tμmn
Membranes with a thickness of less than or equal to 0.055 mm, preferably less than about /θ mil, tend to be most useful. Since the 7 lux of shame tends to increase with a decrease in the 9 lux of 1μ, thinner membranes are generally the more desirable membranes. Of course, the M thickness of the membrane is determined by a number of factors, one of which is the flux, and will vary from the preferred membrane thickness 1 depending on the application.

The semi-permeable membrane of the present invention is used in the same manner as in the case of suitable sound (nI). 'The gas mixture is typically brought into contact with one side of the membrane under pressure, allowing seven or more gaseous components of the mixture to selectively pass through the membrane while the remaining gaseous components are rejected by the membrane. be done. This results in both concentrated portions of the desired gas being produced in one piece 1i11 of the membrane, while both depleted and depleted portions of the same dregs are produced in the other part f11 of the membrane.

Generally, the desired gas is passed through the membrane. That is, in the separation of carbon dioxide from other waste components of natural gas, e
Well, the carbon nitrate passes through the leg, while most of the other gas components are rejected. However, the scum of the mind is generally not rejected by these membranes; these are generally small molecules such as hydrogen or heliud. Similarly, for other gas components of nitrogen, the oxygen component tQff
At f, t, J:, oxygen permeates through the membrane, while nitrogen and other dregs components are selectively rejected. unexploded(
The operating temperature V'1 used during the Mh of 'Jl' can be varied widely. Generally, it is a warm ML used in similar separation methods.

Temperature, force, pressure (among other parameters) vary with the physical strength (among other parameters) such that the membrane is physically and chemically stable.

The following examples are examples of alternative embodiments of the present invention, and unless otherwise specified, all parts and hints are indicative.

Implementation f11 The crab of the demolition book The polymerization book used here is all p
+, lii, "f-equal molecular, [i about '10.000
k Yu-j-Ruho! J (-2, A-zume blue p-
It was based on phenylene oxide (hereinafter referred to as "fL body") (sold by Aldrich Rimikal).

Typical preparation of the mA corded nail platform is performed in chloroform (
Polymer (Otsu 0v) dissolved in bromine (9g 1
) and a glass reactor. The contact or addition time was approximately 5 minutes. The reaction mixture was then stirred at room temperature for an additional 7 hours. The final mixture was precipitated in agitated methanol, and the product polymer was further washed with methanol and dried under reduced pressure to give a product of 97F and 4P. Elemental analysis revealed the bromine content of this product.
1. is about θMIM−%, and the proton N
MR spectroscopy showed that the proepithelium was attached to the aromatic ring portion of 31 (combined).

The above polymer was used to prepare a control polymer, benzyl brominated poly(,2,O-dimethyl-p-phenylene oxide). This production (polymer (70F) dissolved in 15θ01 of tetrachloride, N-bromonuccinimide (
, 2λθV) and benzoyl peroxide (3y).

Then, stir the reaction mixture and heat at 7℃ (for about 4 hours,
It was heated under air surrounding the tatami mat. Q', I of the apothecary offshore platform
Oki'731 of aN and purified 1.1ψ brominated n1-6 body:i
The bromine content of the product polymer is 1-7'i-o. , 3, y+< lai
%Sae) Kotooka Show, PrJ) 7 NMr? Spectrum Ii showed that bromination occurred primarily on the benzyl (methyl) moiety 6J of the U1j coalescence.

Brominated poly(,2, O-dimethyl-p-
Phenylene oxide ) polymer was used to make the membranes tested here, but the hl of Pukodashi Examples 2 and 3,,! U
1. Polymer: Made from Tsumu blend.

A dilute solution (approximately 7-g wt.%) of the dissolved polymer blend in a suitable solvent, typically chloroform, is mixed, poured onto a clean glass plate, and homogenized with the aid of a doctor blade. The mixture was spread evenly on the armpits, air-dried, removed from the glass plate, and dried in air under normal conditions for at least 241 hours to form a film.

A modified Gilbert ellipse was used for the desorption transmission test! The test fA side was exposed to a carbon dioxide/methane/nitrogen mixture trap in a molar ratio of 2.99:3:1:3:3. Remove the permeate with key X' rear gas helium, and then open the sample valve at intervals.
and injected into a gas chromatography column for analysis. The experiment was carried out at 3°C, and the partial pressure of the test gas Fi, 29. g psi, the partial pressure of the product gas on the permeate side is about θ, and the permeation rate I is helium, 2? ,,! Purged with rpsl.

The figures for the disulfide carbon permeability and carbon dioxide/methane selectivity are shown in the r11l table. The polymers making up the membrane are shown under the heading "Polymer" in the railing, and the bromine content of each of these polymers is shown in parentheses following its abbreviation.

Re-PP0u:, ring brominated poly(2,6-dimethyl-〇-phenylene oxide) t, taste L, BR-PPO
Havenzyl brominated poly(Ω,6-dimethyl-p-phenylene oxide) all means, P to S means all poly(arylsulfone).

The separation coefficient is 31 in total according to the following formula.

The permeability coefficient is the product gas ♀% salmon (CC at STP) multiplied by the membrane thickness (crIL), membrane surface area (, ff1) multiplied by the pressure difference across the membrane (cmHg) multiplied by the separation time (sec).
Expressed as the quotient divided by the product of The coefficient /θ1° is used merely for convenience.

Table 1: Force of half-J∆ membrane made from 1t twisted poly(1λ, O-dimethyl-p-phenylene oxide) polymer 8W
4 (Jin L / RB-PPO (da θ%) 2 pieces /
gθ-〇11tRB-PPO(,7,2%), 2θ/'
798 PPO1g
Za7B E3B-PPO (31,%)
/F3 λ Core) Ho,! (JLC, M average molecular weight, YO, OOO, approximately 7% sulfur content, sold by Aldrip Chemical Company).

, 2) with the ffi button.

From the data in Table 1, the term brominated poly(dimethyl-
The membrane formed from the p-phenylene oxide) polymer is
It is clearly seen that membranes formed from similar polymers without groups are also generally superior. As with the carbon dioxide permeability coefficient, the separation polymer was also much higher.

The above operation to determine the selectivity of hydrogenated carbon i and hydrogenated carbon
A mixture of tR element and arthro element in a molar ratio of 7 was used. The test results are shown in the 1M5 table.

of semipermeable membranes made from various substituted poly(,2,t-dimethyl-p-phenylene oxide) polymers, t
Re-PP0 (death) 3za6l-3CBB-
PPO (,74%) 0. From the data in Table 2 and Table 2, it can be seen that ring A-compounded poly(), 6-dimegyl p-phenylene oxide) JR polymerization also produces -t' benzyl brominated and non-A fused forms. I can see that it is.

Although the invention has been described in more detail through the above examples, these are provided merely for illustrative purposes and are not intended to limit the invention.

Claims (1)

[Claims] (1) A portion of the gas mixture is selectively passed through a semi-permeable membrane in such a manner that a concentrated fraction evaporates on one side of the membrane and a fraction forms on the other side of the membrane. a gas mixture containing at least /1i! of CO,, O,,1
O3, O! , H7S is concentrated at least/f111 and the other fractions are CO, ,02, H, S at least /f111 is concentrated, the aromatic group having the following structural formula, or aFi
at least about 50 mole percent of the structural units (θifc is /) of at least seven substituted poly(arylene oxide) polymers containing at least about 2.5-IC1%, based on the total loading of the membrane. An improved method that uses a film containing the 'h' feature. (1) The method according to claim (1), wherein each R is an independent K C, -C, argyl group. (3) The method according to claim (1), wherein each R is a methyl group. (lI) The method of Section (3) in 41 of Patent Documents) J (where each X is a halogen group). (Support) I?
≧ (Phantom method. (6) Claims in which the substituted poly(arylene oxide) polymer contains at least 73 mol % of missing units of the structural formula (IF) (Phantom method. (7) A is zero So 6,6%#″1')if
N (t) (7J method. Claim (7) consisting essentially of the structural unit of (1)
)the method of. (9) The membrane comprises at least 7 M% poly(arylene oxide) polymers, based on the total weight of the membrane, at least about 5
The method of claim (g) comprising θ weight %. Vθ) The membrane contains at least about 75 substituted poly(arylene oxide) M combinations based on the total weight of the membrane.
The nine claims (8) containing % heavy electricity are excluded. V/) In addition, the membrane island is formed from the combination of 7 or more types of substituted poly(xylylene: AW cyto>*%)
¥r The method of claim. r) Insect β pig is brominated poly(2, O-dimethyl-1)
- phenylene oxide) (method of g+. (/11t) The compatible polymer is poly(arylsulfone)
Or poly(6-dimethyl-1)-phenylene oxide) %g'r-jfV range (/3) method. V, 1) The shin circumference of Shunko Kaikyu, whose membrane is a hollow fiber (
1), (9), (//), (/2), fc is V, i)
the method of. (/4) The film has a thickness of approximately /θ mil or less.
'F N Claim 9tl(/,!-) method. (/7) 4? Pour the film as a coating onto the substrate 4? Claim 1#t1(/l, (9), (〃), (/
2), or the method of (/3). (/ff) The method of claim (/7) in which the coated substrate is a hollow fiber. 6
)the method of. Ωθ) Claim MJ (6) in which the gas mixture is air
the method of. 0/) Claims in which the gas mixture is natural gas (/
Method 7). c2.2) Claims in which the gas mixture is air (/
Ka's method.