Method for preparing 2-chlorine-1,1,1,4,4,4-hexafluoro-2-butene by adopting micro-channel reactor

Abstract

The invention discloses a method for preparing 2-chlorine-1,1,1,4,4,4-hexafluoro-2-butene by adopting a micro-channel reactor. The method comprises the following steps: (1) activating the catalyst: introducing a liquid fluorination catalyst and anhydrous HF into a micro-channel reactor to obtain an activated catalyst-HF mixture; and (2) carrying out a fluorination reaction: returning the activatedcatalyst-HF mixture prepared in the step (1) into the micro-channel reactor in the step (1), meanwhile, respectively introducing anhydrous HF and hexachlorobutadiene into the micro-channel reactor from a second path and a third path, conveying a mixture obtained after a reaction to a rectifying tower through a pump, extracting a mixture of 2-chlorine-1,1,1,4,4,4-hexafluoro-2-butene and HF from the top of the rectifying tower, and carrying out layering, wherein the lower layer is 2-chlorine-1,1,1,4,4,4-hexafluoro-2-butene, and the upper layer is HF. The method for preparing 2-chlorine-1,1,1,4,4,4-hexafluoro-2-butene has a high conversion rate, high selectivity and few impurities, and activity of the catalyst is greatly prolonged. The silicon carbide micro-channel reactor is adopted, so that the reaction time is short, superacid corrosion resistance is achieved, reaction mass transfer and heat transfer performance is excellent, and therefore, high activity of the catalyst can be kept for a long time.

Description

technical field

[0001] The invention belongs to the field of organic synthesis, and in particular relates to a method for preparing 2-chloro-1,1,1,4,4,4-hexafluoro-2-butene by using a microchannel reactor. Background technique

[0002] The present invention relates to the first step reaction on the preparation of the fourth generation blowing agent 1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz) by using hexachlorobutadiene as the basic raw material Improvement of the process for the preparation of 2-chloro-1,1,1,4,4,4-hexafluoro-2-butene by liquid-phase fluorination of chloroprene.

[0003] 1,1,1,4,4,4-hexafluoro-2-butene, its ODP is 0, GWP is 5, non-flammable, thermal conductivity close to HFC-365mfc and HFC-245fa. 1,1,1,4,4,4-hexafluoro-2-butene has two isomers, cis and trans, of which cis-hexafluoro-2-butene (Type Z) has a boiling point of 33-34°C, mainly Used to replace HCFC-141b as a blowing agent. Trans-hexafluoro-2-butene (Type E) has a boiling point of 6-8°C and is...

Examples

Embodiment 1

[0025] Catalyst activation:

[0026] SbCl 5 After mixing with anhydrous HF (molar ratio 1:10), pass 20ml / min into a microchannel reactor composed of six 8ml silicon carbide modules connected in series for activation. The activation temperature is 100°C, the pressure is 1MPa, and the residence time is 2.4 minutes. After the material comes out, it enters a gas-liquid separation storage tank with a condenser filled with Ha C alloy packing on the upper part, releases HCl gas, and collects the activated catalyst and HF mixture.

[0027] Fluorination reaction:

[0028] A part of the liquid catalyst and the anhydrous HF mixture that has been activated in step 1 are returned to the microchannel reactor. At the same time, the anhydrous HF and hexachlorobutadiene enter the first reactor module and the The catalyst is mixed, and the liquid flow rate of the mixture through the reactor is 20ml / min, and the molar ratio of the materials is HF: hexachlorobutadiene: SbCl x f 5-x =10:1:1, r...

Embodiment 2

[0030] Catalyst activation:

[0031] SbCl 5 After mixing with anhydrous HF (molar ratio 1:20), pass it into a microchannel reactor composed of six 8ml silicon carbide modules in series at 100ml / min for activation. The activation temperature is 150°C, the pressure is 1.5MPa, and the residence time is 0.48 Minutes, after the material comes out, it enters a gas-liquid separation storage tank with a condenser filled with Ha C alloy packing on the upper part, releases HCl gas, and collects the activated catalyst and HF mixture.

[0032] Fluorination reaction:

[0033] A part of the liquid catalyst and the anhydrous HF mixture that has been activated in step 1 are returned to the microchannel reactor. At the same time, the anhydrous HF and hexachlorobutadiene enter the first reactor module and the The catalyst is mixed, and the liquid flow rate of the mixture through the reactor is 100ml / min, and the molar ratio of the materials is HF: hexachlorobutadiene: SbCl x f 5-x=30:2:1, r...

Embodiment 3

[0035] Catalyst activation:

[0036] TiCl 4 After mixing with anhydrous HF (molar ratio 1:15), pass it into a microchannel reactor composed of six 8ml silicon carbide modules in series at 50ml / min for activation. The activation temperature is 120°C, the pressure is 1.2MPa, and the residence time is 0.96 Minutes, after the material comes out, it enters a gas-liquid separation storage tank with a condenser filled with Ha C alloy packing on the upper part, releases HCl gas, and collects the activated catalyst and HF mixture.

[0037] Fluorination reaction:

[0038] A part of the liquid catalyst and the anhydrous HF mixture that has been activated in step 1 are returned to the microchannel reactor. At the same time, the anhydrous HF and hexachlorobutadiene enter the first reactor module and the The catalyst is mixed, and the liquid flow rate of the mixture through the reactor is 50ml / min, and the molar ratio of the materials is HF: hexachlorobutadiene: TiCl x f 4-x =15:1:1, re...

technical field

[0001] The invention belongs to the field of organic synthesis, and in particular relates to a method for preparing 2-chloro-1,1,1,4,4,4-hexafluoro-2-butene by using a microchannel reactor. Background technique

[0002] The present invention relates to the first step reaction on the preparation of the fourth generation blowing agent 1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz) by using hexachlorobutadiene as the basic raw material Improvement of the process for the preparation of 2-chloro-1,1,1,4,4,4-hexafluoro-2-butene by liquid-phase fluorination of chloroprene.

[0003] 1,1,1,4,4,4-hexafluoro-2-butene, its ODP is 0, GWP is 5, non-flammable, thermal conductivity close to HFC-365mfc and HFC-245fa. 1,1,1,4,4,4-hexafluoro-2-butene has two isomers, cis and trans, of which cis-hexafluoro-2-butene (Type Z) has a boiling point of 33-34°C, mainly Used to replace HCFC-141b as a blowing agent. Trans-hexafluoro-2-butene (Type E) has a boiling point of 6-8°C and is...

Examples

Embodiment 1

[0025] Catalyst activation:

[0026] SbCl 5 After mixing with anhydrous HF (molar ratio 1:10), pass 20ml / min into a microchannel reactor composed of six 8ml silicon carbide modules connected in series for activation. The activation temperature is 100°C, the pressure is 1MPa, and the residence time is 2.4 minutes. After the material comes out, it enters a gas-liquid separation storage tank with a condenser filled with Ha C alloy packing on the upper part, releases HCl gas, and collects the activated catalyst and HF mixture.

[0027] Fluorination reaction:

[0028] A part of the liquid catalyst and the anhydrous HF mixture that has been activated in step 1 are returned to the microchannel reactor. At the same time, the anhydrous HF and hexachlorobutadiene enter the first reactor module and the The catalyst is mixed, and the liquid flow rate of the mixture through the reactor is 20ml / min, and the molar ratio of the materials is HF: hexachlorobutadiene: SbCl x f 5-x =10:1:1, r...

Embodiment 2

[0030] Catalyst activation:

[0031] SbCl 5 After mixing with anhydrous HF (molar ratio 1:20), pass it into a microchannel reactor composed of six 8ml silicon carbide modules in series at 100ml / min for activation. The activation temperature is 150°C, the pressure is 1.5MPa, and the residence time is 0.48 Minutes, after the material comes out, it enters a gas-liquid separation storage tank with a condenser filled with Ha C alloy packing on the upper part, releases HCl gas, and collects the activated catalyst and HF mixture.

[0032] Fluorination reaction:

[0033] A part of the liquid catalyst and the anhydrous HF mixture that has been activated in step 1 are returned to the microchannel reactor. At the same time, the anhydrous HF and hexachlorobutadiene enter the first reactor module and the The catalyst is mixed, and the liquid flow rate of the mixture through the reactor is 100ml / min, and the molar ratio of the materials is HF: hexachlorobutadiene: SbCl x f 5-x=30:2:1, r...

Embodiment 3

[0035] Catalyst activation:

[0036] TiCl 4 After mixing with anhydrous HF (molar ratio 1:15), pass it into a microchannel reactor composed of six 8ml silicon carbide modules in series at 50ml / min for activation. The activation temperature is 120°C, the pressure is 1.2MPa, and the residence time is 0.96 Minutes, after the material comes out, it enters a gas-liquid separation storage tank with a condenser filled with Ha C alloy packing on the upper part, releases HCl gas, and collects the activated catalyst and HF mixture.

[0037] Fluorination reaction:

[0038] A part of the liquid catalyst and the anhydrous HF mixture that has been activated in step 1 are returned to the microchannel reactor. At the same time, the anhydrous HF and hexachlorobutadiene enter the first reactor module and the The catalyst is mixed, and the liquid flow rate of the mixture through the reactor is 50ml / min, and the molar ratio of the materials is HF: hexachlorobutadiene: TiCl x f 4-x =15:1:1, re...