Methods for purifying 5-(halomethyl)furfural
The present disclosure provides methods for purifying a 5-(halomethyl)furfural composition, including 5-(chloromethyl)furfural, at operating conditions that decrease or minimize the decomposition or degradation of 5-(chloromethyl)furfural during the process. The methods may employ certain solvents, operating conditions, and/or techniques (e.g., gas stripping). The gaseous 5-(halomethyl)furfural produced from the process can be condensed or deposited to yield 5-(halomethyl)furfural in liquid or solid form. The solid 5-(halomethyl)furfural may be amorphous or crystalline.
1. A method for purifying 5-(halomethyl)furfural, comprising:
a) providing a 5-(halomethyl)furfural composition to a purification apparatus, wherein the 5-(halomethyl)furfural composition comprises 5-(halomethyl)furfural and one or more impurities, and wherein the 5-(halomethyl)furfural composition has a mass ratio of the one or more impurities to the 5-(halomethyl)furfural;
b) providing a stripping agent to the purification apparatus, wherein the stripping agent has a vapor pressure above the vapor pressure of 5-(halomethyl)furfural; and
c) vaporizing the 5-(halomethyl)furfural in the 5-(halomethyl)furfural composition by contacting the stripping agent with the 5-(halomethyl)furfural composition to form gaseous 5-(halomethyl)furfural, wherein the gaseous 5-(halomethyl)furfural has a mass ratio of the one or more impurities to the 5-(halomethyl)furfural that is lower than the mass ratio for the 5-(halomethyl)furfural composition.
2. The method of claim 1 , further comprising condensing the gaseous 5-(halomethyl)furfural to obtain purified 5-(halomethyl)furfural in liquid form.
3. The method of claim 1 , further comprising depositing the gaseous 5-(halomethyl)furfural to obtain 5-(halomethyl)furfural in solid form.
4. The method of claim 1 , further comprising boiling the 5-(halomethyl)furfural composition in the purification apparatus to obtain a second gaseous 5-(halomethyl)furfural, wherein the second gaseous 5-(halomethyl)furfural has a mass ratio of the one or more impurities to the 5-(halomethyl)furfural that is lower than the mass ratio for the 5-(halomethyl)furfural composition.
5. The method of claim 1 , wherein the 5-(halomethyl)furfural is 5-(chloromethyl)furfural.
6. A method for purifying 5-(halomethyl)furfural, comprising:
a) providing a 5-(halomethyl)furfural composition to a purification apparatus, wherein the 5-(halomethyl)furfural composition comprises 5-(halomethyl)furfural and one or more impurities, and wherein the purification apparatus has an operating temperature of at least 140° C. and an operating pressure of at least 30 torr; and
b) boiling the 5-(halomethyl)furfural composition to obtain gaseous 5-(halomethyl)furfural, wherein the gaseous 5-(halomethyl)furfural has a mass ratio of the one or more impurities to the 5-(halomethyl)furfural that is lower than the mass ratio for the 5-(halomethyl)furfural composition.
7. The method of claim 6 , wherein the operating pressure is between 30 torr and 2000 torr.
8. The method of claim 6 , wherein the 5-(halomethyl)furfural provided to the purification apparatus has less than 30 wt % of the one or more impurities.
9. The method of claim 6 , wherein the 5-(halomethyl)furfural provided to the purification apparatus has less than 5 wt % of residual hydrochloric acid.
10. The method of claim 6 , further comprising condensing the gaseous 5-(halomethyl)furfural to obtain purified 5-(halomethyl)furfural in liquid form.
11. The method of claim 6 , further comprising depositing the gaseous 5-(halomethyl)furfural to obtain purified 5-(halomethyl)furfural in solid form.
12. The method of claim 6 , wherein the 5-(halomethyl)furfural is 5-(chloromethyl)furfural.