NL2029682B1

NL2029682B1 - Mofs material with high gas adsorbability and preparation method and use thereof

Info

Publication number: NL2029682B1
Application number: NL2029682A
Authority: NL
Inventors: Zhang Shuhua; Chen Zhonghang; Xiao Yu; Li Guangzhao
Original assignee: Univ Guilin Technology; Univ Guangdong Petrochem Tech
Priority date: 2020-11-30
Filing date: 2021-11-09
Publication date: 2022-11-15
Also published as: CN112341633B; CN112341633A; NL2029682A

Abstract

The present disclosure mainly relates to the technical field of metal organic framework materials, and in particular disclose an MOFs material with high gas adsorbability and a preparation method and use thereof. The MOFs material is a reaction product of a chemical formula l, a chemical formula 2 and a zinc salt in a solvent, wherein the chemical formula 1 and the chemical formula 2 have specific structures, and the zinc salt is zinc acetate. The MOFs material prepared by using the specific ligand and metal salt in the present disclosure has excellent gas adsorption performance. The present disclosure has a simple process, low cost, easy control of chemical components, good repeatability, high yield, and high selectivity for separating mixed gas of C02 and NZ.

Description

MOFS MATERIAL WITH HIGH GAS ADSORBABILITY AND PREPARATION METHOD AND USE THEREOF

TECHNICAL FIELD The present disclosure mainly relates to the technical field of metal organic framework materials, and more particularly re- lates to an MOFs material with high gas adsorbability and a prepa- ration method and use thereof.

BACKGROUND ART An MOFs material is a porous material, which has a very good application prospect in gas adsorption and separation, wastewater treatment and hydrogen storage materials. Meanwhile, the MOFs ma- terial contains a functional ligand and a metal ion, and thus has the feature of being multifunctional. Designing and synthesizing a novel MOFs material is one of the hot research fields for inorgan- ic chemists and materials scientists. However, most of the MOFs materials in the prior art cannot meet the performance requirement of adsorbing different kinds of gas, and meanwhile their selective adsorption performance for a certain gas is also poor, which leads to the limitation of use of the MOFs material in gas separation. Therefore, it is very necessary to develop an MOFs material with high gas adsorption and selective adsorption performance.

SUMMARY

1. Problem to be solved Aiming at the problems of poor gas adsorption performance and poor selective adsorption performance of MOFs materials in the prior art, the present disclosure provides an MOFs material with high gas adsorbability and a preparation method and use thereof, wherein an MOFs material with excellent gas adsorption and selec- tive adsorption performance is obtained by designing a specific organic ligand and metal salt.

2. Technical solutions In order to solve the aforementioned problems, the technical solutions adopted by the present disclosure are as follows. The present disclosure provides an MOFs material with high gas adsorbability, wherein the MOFs material is a reaction product of a chemical formula 1, a chemical formula 2 and a zinc salt in a solvent: chemical formula 1: 1 3 xl. # X OR NH, Pah NH \ TT 7 - \ N X and/or N- x* in the chemical formula 1, ¥X* is C(RY) or N, X? is C(R*®) (R’) or N(R*), x? is C(R") (R®) or N(R"), and X* is C(R°) (R?) or N(R'"), chemical formula 2: R11 oO 14

R “OH HO. ° 12 | R O R13 in the chemical formula 1 and the chemical formula 2, RR are the same or different and are each independently H or a C1-C10 alkyl or carboxyl or amino or hydroxyl or halogen; wherein the zinc salt is zinc acetate. Preferably, the MOFs material is a reaction product of pyro- mellitic acid, 5-aminotetrazole and zinc salt in a solvent, where- in the zinc salt is zinc acetate. Preferably, a monomer molecule of the MOFs material has a mo- lecular formula of CsHisN:5Zn;0s, a molecular weight of 599.15, and a coordination formula of [Zn;(HATZ) (ATZ). (PMA) s] :{H0)s5,; wherein HATZ is 5-aminotetrazole, and PMA is pyromellitic acid. Preferably, crystal structure data of the MOFs material is:

Table 1. Crystallographic parameters of [Zn (HATZ) (ATZ), (PMA) g.5] : (HzO) 5 T molecular formula CeHiglNieZm0s relative molecular mass 599.15 crystal system orthogonal spatial group Cmcm a (A) 26.1903(7) b (A) 10.3349(3) c (A) 20.6368(7) a (°) 90.00 B (7) 90.00 y (°) 90.00 Vv (À°) 5585.8(3) F(000) 2024 Z 8 De (g cm?) 1.425 u (mm’$) 1.777 8 range (°) 3.685-26.5 Ref. meas. / indep. 22657/3025 Obs. ref.[I > 20 (I)] 2406 Rint 0.061 R* [I 2 20 (I)] © 0.0560 ©wR* (all data)” 0.1697 Goof 1.052 Ap (max, min) (e A?) 0.871, -0.811 TR; = SIF = [FE H/SIFL. © wRe =[Sw{|F21I=| FA EWI FA) FHA Preferably, bond length and bond angle data of the crystal structure of the MOFs material is:

Table 2. Partial bond length (A) and bond angle (°) of [Zn: (HATZ) (ATZ): (PMA)s.s] " (Hz0)s znl-02 1.948 (3) 02-zZnl-N1 114.9014) znl-N4A 2.010(3) O2-Zn1-N7 116.22(17) Znl-N1 1.999 (4) N1-Znl-N4A 112.44 (15) Znl-N7 2.007 (4) N1-Znl-N7 108.95(18) 02-Znl-N4A 103.75 (13) N7-Znl-N4A 99.44 (18) symmetrical operation: (A) -x+3/2, y+1/2, =z.

The present disclosure provides a method for preparing the MOFs material with high gas adsorbability according to any one of the above, including putting pyromellitic acid, 5-aminotetrazole and zinc acetate into a solvent, uniformly mixing and heating the system for reaction, wherein the solvent is water with a resistiv- ity no less than 18 MQ*cm at 25°C.

Preferably, the molar ratio of the added pyromellitic acid, 5-aminotetrazole and Zn (CH,CCO), is 1:1: (1-4).

Preferably, the zinc acetate is Zn{(CH3CO0)2:2H:0.

Preferably, a specific preparation process is: putting 5- aminotetrazole, analytically-pure pyromellitic acid and Zn (CH;COQ), :2H;0 in a reaction kettle, adding water and dissolving under stirring, then adding NaOH, stirring and then reacting at 170°C for 72 h, and cooling to room temperature to obtain the MOFs material.

The present disclosure provides use of the MOFs material with high gas adsorbability according to any one of the above for ad- sorbing CO; and/or N; and/or CH; and/or CH, and/or Csk:.

The present disclosure provides use of the MOFs material with high gas adsorbability according to any one of the above for se- lective separation of CO,.

3. Beneficial effects Compared with the prior art, the beneficial effects of the present disclosure are as follows.

(1) The present disclosure provides an MOFs material with high gas adsorbability, wherein the MOFs material is a reaction product of a chemical formula 1, a chemical formula 2 and a zinc salt in a solvent: chemical formula 1: Xs, Xo, u Ry NH; ed NP Vo No NX and/or N-X4 in the chemical formula 1, X' is C(RY) or N, X? is C{(R%) (R*) or 5 N(R®), X* is C{B) (R®) or N(R"), and X* is C(R") (R*) or N(R*%), chemical formula 2:

RM R14 1

OH

HO | R12 O R13 in the chemical formula 1 and the chemical formula 2, R'-R* are the same or different and are each independently H or a C1-C10 alkyl or carboxyl or amino or hydroxyl or halogen; wherein the zinc salt is zinc acetate. The MOFs material prepared by using the specific ligand and metal salt in the present disclosure has ex- cellent gas adsorption and selective adscrption performance. (2) The present disclosure provides an MOFs material with high gas adsorbability, which is a reaction product of pyromellit- ic acid, 5-aminotetrazole and zinc salt in a solvent, wherein the zinc salt is zinc acetate; an MOFs material with excellent gas ad- sorption and selective adsorption performance is obtained by de- signing the organic ligand and metal salt as pyromellitic acid, 5- aminotetrazole and zinc acetate respectively, wherein a volume that the solvent can pass through in each unit cell (5585.8 A3) of the MOFs material is 2719.4 A3, and the porosity is 48.7%. (3) The present disclosure provides use of the MOFs material with high gas adscrkability for adsorbing CO: with a CO, adsorption capacity of up to 1.290 mmol/g at a temperature of 298.15 K; and/or for adsorbing N; with a N; adsorption capacity of up to

0.133 mmol/g at a temperature of 298.15 K; and/or for adsorbing

C,H; with a C,H; adsorption capacity of up to 1.066 mmol/g at a tem- perature of 298.15 K; and/or for adsorbing CH; with a CH, adsorp- tion capacity of up to 0.467 mmol/g at a temperature of 298.15 K; and/or for adsorbing C:H: with a C:H- adsorption capacity of up to

1.717 mmol/g at a temperature of 298.15 K. Therefore, the MOFs ma- terial exhibits excellent performance for adsorbing CO:, H;0, Nj, CH4, Cy;H, and the like gases, and has wide application in adsorp- tion of gases.

(4) The present disclosure provides use of the MOFs material with high gas adsorbability for selective separation of CO:; the MOFs material can adsorb CO; with high selectivity, and at 298 K and 273 K, the selectivity coefficients S for CO: in binary mixed gas of CO, and N; at a volume ratio of 15:85 are 118 and 145 re- spectively.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a structural diagram of an MOFs material with high gas adsorbability (with an index ellipsoid of 30%, and symmetric codes: (A) -x+3/2, y+1/2, z; (B) -x, +y, 1/2-z; (C) +x, 1-y, 1-z; (D) 1-x, +y, +z; and (E) 1-x, 1-y, 1-z) of the present disclosure.

FIG. 2 is a BET test curve of the MOFs material with high gas adsorbability of the present disclosure, and the inset is a pore size distribution diagram.

FIG. 3 is a curve of adsorption of N, and CH; by the MOFs ma- terial with high gas adsorbability of the present disclosure.

FIG. 4 is a curve of adsorption of C,H. and H,0 by the MOFs material with high gas adsorbability of the present disclosure.

FIG. 5 is a curve of adsorption of CO; by the MOFs material with high gas adsorbability of the present disclosure.

FIG. 6 is a cycle curve of CO: adsorption and desorption by the MOFs material with high gas adsorbability of the present dis- closure under conditions of 298 K and 1 bar.

FIG. 7 is an adsorption schematic diagram of the MOFs materi- al with high gas adsorbability of the present disclosure.

FIG. 8 is an isothermal curve of adsorption of CO:, CH; and N: by the MOFs material with high gas adsorbability of the present disclosure at 298 K.

FIG. 9 shows the adsorption selectivity of the MOFs material with high gas adsorbability of the present disclosure for CO: in binary mixed gas of CO:/N: and COC;/CH; at 298 K.

FIG. 10 is an isothermal curve of adsorption of CO:, CH; and N; by the MOFs material with high gas adsorbability of the present disclosure at 273 K.

FIG. 11 shows the adsorption selectivity of the MOFs material with high gas adsorbability of the present disclosure for CO: in binary mixed gas of CO:/N; and CO;/CH, at 273 K.

DETAILED DESCRIPTION OF THE EMBODIMENTS The present disclosure will be further described below with reference to examples.

Example 1 This example provided a MOFs material with high gas adsorba- bility as shown in FIG. 1, wherein a monomer molecule of it had a molecular formula of CsHieNisZn:05, a molecular weight of 599.15, and a coordination formula of [Zn (HATZ) (ATZ). (PMA); s] - (H:0)s, wherein HATZ was 5-aminotetrazole, and PMA was pyromellitic acid; crystal structure data of it was shown in Table 1, and partial bond length and bond angle data was shown in Table 2; and a volume that a sol- vent could pass through in each unit cell (5585.8 A’) of the MOFs material was 2719.4 A®, and the porosity was 48.7%.

This example also provided a method for preparing a MOFs ma- terial with high gas adsorbability, specifically including the following steps.

Analytically-pure 5-aminotetrazole (0.5 mmol, 0.043 g), ana- lytically-pure pyromellitic acid (0.25 mmol, 0.064 g) and analyti- cally-pure Zn{CH3COO)::2H:0 {0.5 mmol, 0.110 g) were weighed and put into a 20 mL reaction kettle, added with 10 mL of ultrapure water, dissolved under stirring, then added with analytically-pure NaOH (1.5 mmol, 0.060 g), stirred at room temperature for 30 min, then put into a 170°C oven to react for 72 hours, and then taken out and slowly cooled to room temperature. The reaction solution was filtered and washed with ultrapure water for three times to obtain a transparent block crystal with an output of 0.041 g and a yield of 48.18% (based on HATZ). The [Zn (HATZ) (ATZ),

(PMA) 45.5] + (H:0)s was determined for structure by a single-crystal diffractometer. The crystal structure data of it was shown in Ta- ble 1, and partial bond length and bond angle data was shown in Table 2.

As shown in FIG. 2, in order to explore the stability of the pore structure of the MOFs material of this example, a BET test was carried out on it, i.e., the adsorption of N, at 77 k. The re- sult showed that the adsorption capacity of N; by the MOFs material with high gas adsorbability of this example reached 116.0 cm’/g at 1 atm, with a specific surface area of 354.63 m?/g, a pore volume of a micropore of 0.178 cm’/g, and a pore diameter of 0.5-0.9 nm, which belonged to a typical physical adsorption, indicating that the MOFs material of this example was a microporous material.

In order to study the adsorption performance of the MOFs ma- terial with high gas adsorbability of this example for each gas, an adsorption isothermal curve test was conducted on CO:, H;0, Ni, CH; and C;H. gas respectively.

As shown in FIG. 3, the adsorption capacity of N, could reach

0.302 mmol/g and 0.133 mmol/g at temperatures of 273.15 K and

298.15 K respectively. FIG. 4 showed a adsorption isothermal curve of the MOFs material of this example for CH, and H;0 at 298.15 K, and the results showed that the adsorption capacities of it were

1.717 mmol/g and 1.066 mmol/g, respectively. FIG. 5 showed a ad- sorption isothermal curve of the MOFs material of this example for CO: at 273.15 K and 298.15 K, and the results showed that the ad- sorption capacities of it were 2.117 mmol/g and 1.290 mmol/g, re- spectively. Therefore, the MOFs material with high gas adsorbabil- ity of the present disclosure exhibited excellent adsorption per- formance for all of CO, H;0, Nz, CH; and C:H: gas.

Furthermore, as shown in FIG. 6, in addition to excellent ad- sorption performance, the MOFs material of this example also had excellent cycle stability. In this example, the cycle stability of it in CO, adsorption and desorption was also tested, and the re- sults showed that the adsorption capacity of CO, remained basically unchanged after 11 adsorption-desorption cycles, so the MOFs mate- rial [Zn: (HATZ) (ATZ)- (PMA);.s] :(H:0)s5 of the present disclosure can be used as a cheap and stable CO: adsorption material.

As shown in FIG. 7, in this example, in order to explore the adsorption mechanism of the MOFs material for each gas, adsorption sites of individual gas molecules in the skeleton of the MOFs ma- terial were studied by a quantum chemistry method, and their ad- sorption energies were calculated. A specific calculation method was as follows.

a. Firstly, a model was established through diamond software by using data in a crystallography.cif format, and subjected to optimization of molecular structure by a Dmol3 module in Materials Studio to obtain a reliable geometric configuration.

b. Several configurations of various gas molecules were built through Materials Studio, and subjected to configuration optimiza- tion of guest molecules by the Dmol3 module to obtain a reliable geometric configuration.

c. On the basis of optimizing the geometric configurations of the MOF skeleton and the guest molecules, the guest molecules were placed at different positions in the skeleton, the MOF skeleton was subjected to position fixing, and then optimization of molecu- lar configuration was conducted by the Dmol3 module to obtain a stable geometric configuration after the guest molecules were ad- sorbed.

The results of quantum chemistry calculation showed that there were two categories of CO, adsorption sites in the channel, the first one is the site which only interacted with 5- aminotetrazole {N-H:::O = 2.464-2.991 Ay, and the other one was located among pyromellitic acid ligands and interacted with an un- coordinated oxygen atom on pyromellitic acid (C::-:0 = 2.877-2.880 A, N-H:::0 = 2.647-2.924 A). The adsorption energies of these two interactions were -25.556 kJ mol” and -20.065 kJ ‘mol, respective- ly. Therefore, the first category of adsorption sites was the main form of CO: interacting with the skeleton in the channel.

As shown in FIGs. 8 and 10, in this example, the adsorption isothermal curves of CO:, N; and CH, respectively at 298 K and 273 K were compared, and it could be seen that the MOFs material of this example had a higher adsorption capacity for CO: than those for N; and CH. This result was consistent with the aforementioned adsorption mechanism. Therefore, based on this adsorption mecha-

nism, the MOFs material of this example also had excellent selec- tive adsorption performance.

As shown in FIGs. 9 and 11, in this example, the separation selectivity of the MOFs material for mixtures of CO,/N, (15:85) and CO;/CH; (10:90) at 273 k and 298 K was evaluated by using ideal ad- sorption solution theory (IAST) calculation. It could be seen that the excellent adsorption selectivity for CO./N. (15:85) reached 118 and 145 respectively, the adsorption selectivity for CO:/CH4 (10:90) calculated under the same conditions was 10, and CO: could be effectively separated from both of the mixed gas.

Therefore, the MOFs material with high gas adsorbability of this example, due to its rich porous structures and adsorption sites, not only exhibited excellent adsorption performance for gas such as CO:, H:O, Ns, CH; and C;H,, but also had a certain selective separation effect for CO,, C,H, and H;0, and thus could be used as a functional material for gas adsorption and separation.

The present disclosure has been described in detail above with reference to specific exemplary examples. However, it should be understood that various modifications and variations can be made without departing from the scope of the invention as defined by the appended claims. The detailed description and accompanying drawings should be regarded as illustrative only, rather than re- strictive, and if there are any such modification and variation, they will all fall within the scope of the invention described herein. Moreover, the background art is intended to illustrate the research and development status and significance of this technolo- gy, and is not intended to limit the present disclosure or the present application and application fields of the present disclo- sure.

More specifically, although exemplary embodiments of the pre- sent disclosure have been described here, the present disclosure is not limited to these embodiments, and includes any and all em- bodiments that are modified, omitted, combined (for example, among various embodiments), adapted and/or replaced as recognized by those skilled in the art according to the foregoing detailed de- scription, and various embodiments of the present disclosure can be combined as desired. The definitions in the claims can be broadly interpreted according to the language used in the claims, and are not limited to the examples described in the foregoing de- tailed description or during the implementation of the present ap- plication.

These examples should be regarded as non-exclusive.

Any steps listed in any method or process claim may be performed in any order and are not limited to the order set forth in the claims.

Therefore, the scope of the present disclosure should be determined only by the appended claims and their legal equiva- lents, and not by the descriptions and examples given hereabove.

Claims

CONCLUSIONS

1. MOFs material with high gas adsorbability, where the MOFs material is a reaction product of a chemical formula 1, a chemical formula 2 and a zinc salt in a solvent: chemical formula 1: Xa, Xx, - ~~ NR NH, AN NH: \ ' "\ rer N X and/or N X where in the chemical formula 1, X' represents C(R') or N, Xx represents C(R*) (RY) or N (R*), Xx ' represents C(RY(R®) or N(R"), and X* represents C(RY)(R?) or N(R'), chemical formula 2: R11 o 14 R |

OH

HO | R12 Ö 13

R wherein in chemical formula 1 and chemical formula 2 R 1 -R* are the same or different and each independently represents H or a C 1 -C 2 ; alkyl or carboxyl or amino or hydroxyl or halogen; wherein the zinc salt is zinc acetate.

The MOFs material with high gas adsorbability according to claim 1, wherein a monomer molecule of the MOFs material has a molecular formula of CsHisN;52n:Os, a molecular weight of 599.15 and a coordination formula of [Zn; (HATZ)(ATZ}, (PMA}5,s] :(H:0): where HATZ is 5-aminotetrazole and PMA is pyromellitic acid.

The high gas adsorbability MOFs material according to claim 1, wherein the crystal structure data of the MOFs material is:

crystal system: orthogonal; spatial group: Cmcm; a(A): 26.1903(7) + 1; b(A): 10.3349(3) + 1; c(A): 20.6368(7) + 1; a (°°): 90.00; B (°): 90.00; y (°): 90.00; V (A3): 5585.8(3) + 50.

The high gas adsorbability MOFs material according to claim 1, wherein the bond length and bond angle data of the crystal structure of the MOFs material are: Zn1-02 1.948 (3) 02-Znl-N1 114.90(14) ZnI-N4A 2.010(3) 02-Znl-N7 116.22 (17) Znl-N1 1.999 (4) N1-Znl-N4A 112.44 (15) Znl-N7 2.007 (4) N1-Znl-N7 108.95(18 ) 02-Zn1-N4A 103.75(13) N7-Zn1-N4A 99.44 (18) symmetrical operation: (A) -x+3/2, y+1/2, =z.

A process for preparing high gas adsorbability MOFs material according to any one of claims 1 to 4, comprising putting pyromellitic acid, 5-aminotetrazole and zinc acetate into a solvent, mixing uniformly and heating the system for reaction, wherein the solvent is water having a resistivity of not less than 18 MΩ*cm at 25°C.

The method for preparing the high gas adsorbability MOFs material according to claim 5, wherein the molar ratio of the added pyromellitic acid, 5-aminotetrazole and Zn (CH 2 COO) is 1:1:(1-4) .

The method for preparing the high gas adsorbability MOFs material according to claim 5, wherein the zinc acetate is Zn(CH:COO)-:2H,0.

The method for preparing the high gas adsorbability MOFs material according to claim 5, wherein a specific preparation process is: placing 5-aminotetrazole, analytically pure pyromellitic acid and Zn {CH 2 COOO ) .2H;C, in a reaction vessel adding water and dissolving with stirring, then adding NaOH, stirring and then reacting at 140-180°C for 48-120 hours and cooling to room temperature to obtain the MOFs material.

Use of the high gas adsorbability MOFs material according to any one of claims 1-4 for adsorbing CO 1 and/or N and/or H 2 O and/or CH; and/or C.H.

Use of the high gas adsorbability MOFs material according to any one of claims 1-4 for selective separation of CO 2 .