Regeneration method for Cu-BTC material

Abstract

A method for regenerating a Cu-BTC material includes: impregnating a Cu-BTC adsorbed with guest molecules in an acidic proton solvent or in a steam environment thereof, and filtering the Cu-BTC material, to obtain a solid; impregnating the solid in a non-acidic organic solvent or a steam environment thereof, and finally filtering, washing and drying the solid, to complete the generation of the Cu-BTC material.

Claims

1. A method for regenerating a Cu-BTC material, comprising: impregnating Cu-BTC adsorbed with guest molecules in an acidic proton solvent or a steam environment thereof, and filtering the Cu-BTC material to obtain a solid; and impregnating the solid in a non-acidic organic solvent or a steam environment thereof, and finally filtering, washing and drying the solid, to complete the regeneration of the Cu-BTC material; wherein the acidic proton solvent has a pH value of 1 to 6.

2. The method according to claim 1, wherein the guest molecules are gas molecules or organic dye molecules.

3. The method according to claim 1, wherein the specific surface area of the Cu-BTC adsorbed with guest molecules is greater than 600 m.sup.2/g, and the specific surface area of the Cu-BTC material is greater than 600 m.sup.2/g.

4. The method according to claim 1, wherein the acidic proton solvent is at least one member selected from the group consisting of acetic acid, formic acid, hydrochloric acid, sulfuric acid, nitric acid, carbonic acid, phosphoric acid, hydrofluoric acid, hydrogen bromide and hydrogen iodide.

5. The method according to claim 1 or 4, wherein when the Cu-BTC adsorbed with guest molecules is impregnated in the acidic proton solvent, a value of the liquid volume of the acidic proton solvent in milliliters is 20 folds or more than a value of the solid mass in grams; and the Cu-BTC adsorbed with guest molecules is impregnated in the acidic proton solvent or the steam environment thereof for a duration of 1 min to 72 h.

6. The method according to claim 1, wherein the non-acidic organic solvent is at least one member selected from the group consisting of methanol, ethanol, N,N-dimethylformamide, dimethyl sulfoxide, acetonitrile, sulfolane, acetone, dimethylacetamide and hexamethylphosphoramide.

7. The method according to claim 1, wherein a value of the liquid volume of the non-acidic organic solvent in milliliters is 10 folds or more than a value of the solid mass in grams.

8. The method according to claim 1, wherein the solid is impregnated in the non-acidic organic solvent for a duration of 1 min to 72 h.

9. The method according to claim 1, wherein the guest molecules are one or more members selected from the group consisting CO.sub.2, CO, N.sub.2, H.sub.2, CH.sub.4, C.sub.2H.sub.2, C.sub.2H.sub.4, NO, NO.sub.2, SO.sub.2, H.sub.2S, methyl orange, methyl blue, methylene blue, methyl red and Sudan red.

10. The method according to claim 1, wherein the guest molecule adsorption in the Cu-BTC adsorbed with guest molecules is 0.1 wt % to 100 wt %.

11. The method according to claim 2, wherein the guest molecule adsorption in the Cu-BTC adsorbed with guest molecules is 0.1 wt % to 100 wt %.

12. A method for regenerating a Cu-BTC material, comprising: impregnating Cu-BTC adsorbed with guest molecules in an acidic proton solvent or a steam environment thereof, and filtering the Cu-BTC material to obtain a solid, wherein the solid is obtained without decomposing the structure of the Cu-BTC material; and impregnating the solid in a non-acidic organic solvent or a steam environment thereof, and finally filtering, washing and drying the solid, to complete the regeneration of the Cu-BTC material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The disclosure will become more fully understood from the detailed description given herein below for illustration only, and thus are not limitative of the disclosure, and wherein:

(2) FIG. 1 is a comparison diagram of XRD patterns before and after regeneration of Cu-BTC in Embodiment 1,

(3) a) the structure of Cu-BTC before regeneration; b) the structure of Cu-BTC after regeneration; and

(4) FIG. 2 shows CO.sub.2 adsorption curves before and after regeneration of Cu-BTC in Embodiment 1, CO.sub.2 adsorption curves a) before regeneration and b) after regeneration of Cu-BTC at normal temperature and normal pressure.

DETAILED DESCRIPTION

(5) The present invention is further described below with reference to the following embodiments.

(6) In the following implementation, the experimental methods are conventional methods unless otherwise stated; all reagents or raw materials are commercially available unless otherwise stated.

Embodiment 1

(7) 1 g Cu.sub.3 (C.sub.9H.sub.3O.sub.6).sub.2.3H.sub.2O (Cu-BTC) adsorbed with saturated CO.sub.2 having a specific surface area of 1123.6 m.sup.2/g and a pore volume of 0.46 cm.sup.3/g was impregnated in 50 ml hydrochloric acid solution at pH=1, reacted for 10 min with stirring and filtered to obtain a solid. The solid was impregnated in 50 ml N,N-dimethylformamide solution, reacted for 5 min with stirring, filtered out the solid and dried, to complete the regeneration of Cu-BTC. For the regenerated Cu-BTC, the specific surface area was 1052.7 m.sup.2/g, and the pore volume was 0.46 cm.sup.3/g.

Embodiments 2 to 10

(8) Embodiments 2 to 10 were carried out according to the steps in Embodiment 1, and the raw materials and conditions for specific reactions were shown in Table 1. In Embodiment 9, the adsorbed guest molecules were organic dye molecules, and in Embodiment 10, a saturated steam was used for impregnation. The structure and the performance of the product were shown in Table 2.

(9) TABLE-US-00001 TABLE 1 Raw materials and preparation conditions in Embodiments 2 to 10 Control conditions Folds of Folds of the Adsorbed liquid volume pH of organic solvent Other guest relative to the the Duration relative to the Duration embodiments molecules solid mass (mL/g) Acid solution solution min Organic solvent solid mass (mL/g) min Embodiment 2 CO.sub.2 20 nitric acid 1 3 dimethyl sulfoxide 10 3 Embodiment 3 N.sub.2 100 acetic acid 4 10 methanol steam 20 5 Embodiment 4 C.sub.2H.sub.4 30 sulfuric acid 2 5 ethanol 50 15 Embodiment 5 H.sub.2 50 nitric acid 6 10 sulfolane 30 10 Embodiment 6 NO 100 phosphoric 5 10 acetonitrile 40 10 acid Embodiment 7 O.sub.2 50 formic acid 3 8 dimethylacetamide 30 10 Embodiment 8 SO.sub.2 40 sulfuric acid 1.5 5 hexamethylphosphoramide 20 8 Embodiment 9 methyl 50 sulfuric acid 1.5 5 dimethylformamide 30 8 orange Embodiment 10 H.sub.2S / hydrochloric 3 60 acetone steam / 30 acid steam

(10) TABLE-US-00002 TABLE 2 Structure and properties of the products of Embodiments 2 to 10 Structure and properties of the regenerated solid CuBTC CuBTC (after regeneration) specific pore specific pore Other surface area volume surface area volume embodiments (m.sup.2/g) (cm.sup.3/g) (m.sup.2/g) (cm.sup.3/g) Embodiment 2 1123.6 0.46 1105.3 0.46 Embodiment 3 1123.6 0.46 1090.5 0.46 Embodiment 4 1123.6 0.46 1116.7 0.46 Embodiment 5 1123.6 0.46 1108.4 0.46 Embodiment 6 1123.6 0.46 1120.1 0.46 Embodiment 7 1123.6 0.46 1078.6 0.46 Embodiment 8 1123.6 0.46 1095.7 0.46 Embodiment 9 1123.6 0.46 1054.3 0.46 Embodiment 10 1123.6 0.46 1100.3 0.46

Comparative Example 1

(11) 1 g Cu-BTC adsorbed with saturated CO.sub.2 having a specific surface area of 1123.6 m.sup.2/g and a pore volume of 0.46 cm.sup.3/g was impregnated in 50 ml hydrochloric acid solution at pH=6.5, reacted for 30 min with stirring and filtered to obtain a solid. The solid was impregnated in 20 ml N,N-dimethylformamide solution, reacted for 10 min with stirring, filtered out the solid and dried. The structure of the solid was changed, where the specific surface area was 320.76 m.sup.2/g, and the pore volume was 0.25 cm.sup.3/g.

Comparative Example 2

(12) 1 g Cu-BTC adsorbed with saturated CO.sub.2 having a specific surface area of 1123.6 m.sup.2/g and a pore volume of 0.46 cm.sup.3/g was impregnated in 50 ml hydrochloric acid solution at pH=0.8, reacted for 5 min with stirring and filtered to obtain a solid. The solid was dried to obtain a white particle, and the solid was impregnated in 20 ml N,N-dimethylformamide solution, reacted for 10 min with stirring, filtered out the solid and dried. The structure of the solid was changed, where the specific surface area was 11.546 m.sup.2/g, and the pore volume was 0.023 cm.sup.3/g.

(13) Comparative Examples 1 and 2 indicate that when the acid is excessively strong or weak, regeneration of Cu-BTC cannot be realized, and moreover, when the acid concentration is excessively low, the structure of the regenerated Cu-BTC is changed, Cu-BTC is directly decomposed and cannot be regenerated.

Comparative Example 3

(14) 1 g metal organic framework compound Cu.sub.3 (C.sub.9H.sub.3O.sub.6).sub.2.3H.sub.2O (Cu-BTC) adsorbed with saturated CO.sub.2 having a specific surface area of 1123.6 m.sup.2/g and a pore volume of 0.46 cm.sup.3/g was impregnated in 15 ml hydrochloric acid solution at pH=2, reacted for 10 min with stirring and filtered to obtain the reaction product. The reaction product was impregnated in 15 ml N,N-dimethylformamide solution, reacted for 5 min with stirring and filtered to obtain a solid. The solid was washed and dried, to obtain Cu-BTC, where the specific surface area was 810.25 m.sup.2/g, and the pore volume was 0.36 cm.sup.3/g.

(15) Comparative Example 3 indicate that when the ratio of the liquid volume to the solid mass is too low, the guest molecules in Cu-BTC cannot be completely desorbed, and Cu-BTC cannot be completely regenerated.