Method for adsorption separation of propylene and propyne

Abstract

A method for the adsorption separation of propylene and propyne, comprising selectively adsorbing propyne from a mixed gas of propylene and propyne using an anion-containing metal-organic framework material as an adsorbing agent so as to obtain a purified propylene gas. The anion-containing metal-organic framework material is used as an adsorbing agent in the method, and the adsorbing agent is a kind of highly ordered microporous organic-inorganic hybrid material, with the pore size thereof being adjustable within the range of 0.4-1.2 nm, and the pore volume thereof being adjustable within the range of 0.1-1.2 cm3/g. A large number of anionic active sites and a highly ordered spatial arrangement thereof allow the adsorbing agent to exhibit excellent propyne adsorption properties. Thus, the adsorbing agent has a very high propyne selectivity and adsorption volume.

Claims

1. A method of separating propyne from propene using metal-organic framework materials to obtain a propene product with a reduced amount of propyne, comprising selectively adsorbing propyne from a mixed gas comprising propene and propyne using anion-containing metal-organic frameworks as an adsorbent, wherein the anion-containing metal-organic framework materials are selected from first-class materials or second-class materials: first-class materials prepared by first coordinating a metal ion M1 and an organic ligand L1 to form two-dimensional frameworks, and then bridging the two-dimensional frameworks by an inorganic ligand L2 to form three-dimensional frameworks, thereby obtaining the first-class materials; wherein the metal ion M1 is selected from the group consisting of Zn.sup.2+, Cu.sup.2+, Ni.sup.2+, Co.sup.2+, Mg.sup.2+, Al.sup.2+, and a combination thereof; wherein the inorganic ligand L2 is selected from the group consisting of SiF.sub.6.sup.2, TiF.sub.6.sup.2, SnF.sub.6.sup.2, ZrF.sub.6.sup.2, GeF.sub.6.sup.2, and a combination thereof; wherein the organic ligand L1 is selected from any of the following: ##STR00006## where R is selected from any of the following groups: ##STR00007## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, and R.sub.8 are each selected from the groups H, F, Cl, Br, I, CH.sub.3, NH.sub.2, OH, SO.sub.3H, COOH, and CF.sub.3; and second-class materials being porous framework materials formed by assembling the metal ion M1, a bio-organic ligand L3, and the inorganic anion L2 through coordination bond and hydrogen bond; wherein the organic ligand L3 is selected from any of the following: ##STR00008##

2. The method of separating propyne from propene using metal-organic framework materials according to claim 1, wherein the anion-containing metal-organic framework materials are the first class of materials, among which: the metal ion M1 is selected from the group consisting of Zn.sup.2+, Cu.sup.2+, Ni.sup.2+, and a combination thereof; the inorganic ligand L2 is selected from the group consisting of SiF.sub.6.sup.2, TiF.sub.6.sup.2, SnF.sub.6.sup.2, and a combination thereof; the organic ligand L1 is selected from the group consisting of pyrazine, 4,4-dipyridylacetylene, 4,4-bipyridine, and a combination thereof.

3. The method of separating propyne from propene using metal-organic framework materials according to claim 2, wherein the L2 is SiF.sub.6.sup.2.

4. The method of separating propyne from propene using metal-organic framework materials according to claim 1, wherein the anion-containing metal-organic framework materials are the second-class materials, among which: the metal ion M1 is selected from the group consisting of Zn.sup.2+, Cu.sup.2+, Ni.sup.2+, and a combination thereof; the bio-organic ligand L3 is adenine; and the inorganic ligand L2 comprises one or more is selected from the group consisting of SiF.sub.6.sup.2 and TiF.sub.6.sup.2.

5. The method of separating propyne from propene using metal-organic framework materials according to claim 1, wherein a concentration of propyne in the propene product is below 1 ppm, and the regeneration of the adsorbent includes vacuum, heating, or heating with an inert gas flow.

6. The method of separating propyne from propene using metal-organic framework materials according to claim 1, wherein an adsorption temperature is between 0-40 C.

7. The method of separating propyne from propene using metal-organic framework materials according to claim 6, wherein a pressure for the adsorption and separation is 0.5-10 atm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows the breakthrough curve of the SIFSIX-2-Cu-i for propylene/propyne (99/1, v/v) separation in the example 1.

(2) FIG. 2 shows the breakthrough curve of the SIFSIX-1-Cu for propylene/propyne (99/1, v/v) separation in the example 5.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Example 1

(3) A methanol solution (4.0 mL) of 4,4-bipyridylacetylene (46.44 mg) was mixed with an aqueous solution (4.0 mL) of 89 mg Cu(BF.sub.4).sub.2.xH.sub.2O (metal ion M1) and 45.96 mg (NH.sub.4).sub.2SiF.sub.6 (inorganic anion ligand L2) and then heated at 40-100 C. for 12-36 hours. The obtained SIFSIX-2-Cu-i (SiF.sub.6.sup.2 inorganic anion ligand) was further filtered and then immersed in the methanol. The activated adsorbent was loaded into the column (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture was introduced into the column at 1.25 mL/min under 25 C. During the first 220 min, propylene only with trace propyne (below 1 ppm) was obtained. The adsorption was stopped. The column with adsorbed propyne was desorbed under vacuum at 50 C. and then could be reused.

Example 2

(4) The column illustrated in the example 1 (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture with 1000 ppm CO.sub.2 was introduced into the column at 1.25 mL/min under 25 C. During the first 210 min propylene with trace propyne (below 1 ppm) was obtained. The adsorption was stopped. The column with adsorbed propyne was desorbed under vacuum at 30 C. and then could be reused.

Example 3

(5) The column illustrated in the example 1 (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture with 2000 ppm water was introduced into the column at 1.25 mL/min under 25 C. During the first 215 min propylene with trace propyne (below 1 ppm) was obtained. The adsorption was stopped. The column with adsorbed propyne was desorbed under vacuum at 80 C. and then could be reused.

Example 4

(6) The column illustrated in the example 1 (inner diameter 4.6 mm, length 50 mm), the propylene with 1000 ppm propyne was introduced into the column at 1.25 mL/min under 40 C. During the first 350 min, propylene with trace propyne (below 1 ppm) was obtained. The adsorption was stopped. The column with adsorbed propyne was purged by He at 60 C.

Example 5

(7) The aqueous solution of 0.28 g Cu(BF.sub.4).sub.2.xH.sub.2O (metal ion M1) and 0.199 g (NH.sub.4).sub.2SiF.sub.6 (inorganic anion ligand L2) was added into the glycol solution of 0.35 g 4,4-bipyridyl (organic ligand L1) and then heated below 100 C. for 2-8 hours. The obtained violet powder SIFSIX-1-Cu (SiF.sub.6.sup.2 inorganic anion ligand) was further filtered and then activated. The activated adsorbent was loaded into the column (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture was introduced into the column at 1.25 mL/min under 25 C. During the first 180 min, propylene with only with trace propyne (below 1 ppm) was obtained. The adsorption was stopped. The column with adsorbed propyne was desorbed under vacuum at 40 C. and then could be reused.

Example 6

(8) The column illustrated in the example 5 (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (50/50, v/v) mixture was introduced into the column at 1.25 mL/min under 20 C. During the first 65 min, propylene with only with trace propyne (below 5 ppm) was obtained. The adsorption was stopped. The column was purged by He flow under 60 C. for regeneration.

Example 7

(9) The column illustrated in the example 5 (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (90/10, v/v) mixture was introduced into the column at 5 mL/min under 20 C. During the first 25 min, propylene with trace propyne (below 1 ppm) was obtained. The adsorption was stopped. The column were purged by He flow under 60 C. for regeneration.

Example 8

(10) 1 mmol Ni(NO.sub.3).sub.2 (metal ion M1), 1 mmol (NH.sub.4).sub.2SiF.sub.6 and 2 mmol pyrazine (organic ligand L1) was added in the 20 mL methanol solution and stirred at 60-80 C. for 2-4 days. The obtained product SIFSIX-3-Ni (SiF.sub.6.sup.2 inorganic anion ligand) was further filtered and then activated. Then, the activated adsorbent was loaded into the column (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture was introduced into the column at 1.25 mL/min under 25 C. During the first 45 min, only propylene with trace propyne (below 1 ppm) was obtained. The adsorption was stopped. The column with adsorbed propyne was desorbed under vacuum at 60 C.

Example 9

(11) A methanol solution (4 mL) of 46 mg 4,4-bipyridylacetylene (organic ligand L1) was mixed with an aqueous solution of 89 mg Cu(BF.sub.4).sub.2.xH.sub.2O (metal ion M1) and 61 mg (NH.sub.4).sub.2TiF.sub.6 (inorganic anion ligand L2) and then heated below 85 C. for 12 hours. The obtained product TiFSIX-2i-Cu-i (TiF.sub.6.sup.2 inorganic anion ligand) was further filtered and then activated. The activated adsorbent was further loaded into the column (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture was introduced into the column at 1.25 mL/min under 25 C. During the first 230 min, only propylene with trace propyne (below 1 ppm) was obtained. The adsorption was stopped. The column with adsorbed propyne was desorbed under vacuum at 50 C. and then could be reused.

Example 10

(12) A methanol solution (4 mL) of 46.44 mg 4,4-bipyridylacetylene (organic ligand L1) was mixed with an aqueous solution of 89 mg Cu(BF.sub.4).sub.2.xH.sub.2O (Metal Ion M1) and 69.18 mg (NH.sub.4).sub.2SnF.sub.6 (inorganic anion ligand L2) and then heated below 40-100 C. for 12-36 hours. The obtained product SNFSIX-2-Cu-i (SnF.sub.6.sup.2 inorganic anion ligand) was further filtered and then activated. The activated adsorbent was loaded into the column (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture was introduced into the column at 1.25 mL/min under 25 C. During first 215 min, only propylene with trace content of propyne (below 1 ppm) was obtained. The adsorption was stopped. The column with adsorbed propyne was desorbed under vacuum at 50 C. and then could be reused

Example 11

(13) The aqueous solution of 17.6 mg Cu(NO.sub.3).sub.2.2.5H.sub.2O (metal ion M1) and 15 mg (NH.sub.4).sub.2TiF.sub.6 (inorganic anion ligand L2) was firstly placed in the tube, then an acetonitrile/water (1:1) solution of 20.5 mg adenine (organic ligand L3) was layered on the aqueous solution. The violet crystal MPM-1-TIFSIX was obtained after 4 days (the second kinds of materials described in appended claim). Then, the activated adsorbent was loaded into the column (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture was introduced into the column at 1.25 mL/min under 30 C. During the first 50 min, propylene only with low content of propyne (below 20 ppm) was obtained. The adsorption was stopped. The adsorbed propylene was desorbed under vacuum at 50 C.

Example 12

(14) 0.59 g of 2,5-dihydroxybenzene-1,4-dicarboxylic acid (organic ligand L4) and 0.24 g Mg(NO.sub.3).sub.2.9H.sub.2O (metal ion M1) were dissolved in the dimethylformamide, ethanol and water mixed solution and heated under 120 C. The obtained product Mg.sub.2(dobpdc) was immersed in the dimethylformamide for 4 days and dried under the vacuum at 180 C. 1.94 g of 4-trifluoromethyl phenol (organic anion X1) was dissolved in the anhydrous triglycol, meanwhile, 8.57 mL tetrahydrofuran with N, N-Diisopropylformamide was dropwise added in anhydrous triglycol. Both the tetrahydrofuran and N,N-Diisopropylformamide were removed after two hours and then the triglycol solution mixed with 125 mg Mg.sub.2(dobpdc), reacting for 7 days at 80 C. The obtained product (the third kinds of materials in the appended claim) was further activated. Then, the activated adsorbent was loaded into the column (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1, v/v) mixture was introduced into the column at 2 mL/min under 25 C. During the first 30 min, only propylene with low content of propyne (below 25 ppm) was obtained. The adsorption was stopped. The adsorbed propylene was desorbed under vacuum at 30 C.

Example 13

(15) 1.85 g of 2,5-dihydroxybenzene-1,4-dicarboxylic acid (organic ligand L4), 2.85 g anhydrous FeCl.sub.2 (Metal Ion M1), 400 mL dimethylformamide and 50 mL anhydrous methanol were added into the reactor. The kelly product was obtained after stirring for 24 hours at 120 C. Exchange the original solution with fresh anhydrous DMF for several times and finally wash with methanol. The obtained product Fe.sub.2(dobpdc) was dried under the vacuum at 250 C. 13.8 mg of Fe.sub.2(dobpdc) was added into the acetonitrile solution in the glovebox and stirred. 26 mg of C.sub.12H.sub.8S.sub.2PF.sub.6.sup.2 (inorganic anion X2) was dissolved in the 4 mL acetonitrile and then dropwise added into the above prepared acetonitrile solution and sealed. The product was obtained after 15-24 hours at room temperature. Fe.sub.2(dobpdc)(PF.sub.6) 1.565.1MeCN (the fourth kinds of materials in the appended claim). Then, the activated adsorbent was loaded into the column (inner diameter 4.6 mm, length 50 mm), the propylene/propyne (99/1) mixture was introduced to flow into the column at 1.25 mL/min under 25 C. During the first 40 min, only propylene with low content of propyne (below 30 ppm) was obtained. The adsorption was stopped. The adsorbed propylene was desorbed under vacuum at 30 C.

(16) Furthermore, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, not for the purpose of limiting the invention as defined by the appended claims and their equivalents. Although only the selected embodiments have been chosen to illustrate the present invention, the all involved change or modification without departing from the scope of the invention as defined in the appended claims are covered in this invention.