A kind of thioether oxidation method

Abstract

The invention discloses a sulfide oxidation method, which comprises continuously feeding a liquid mixture into a fixed-bed reactor, making the liquid mixture flow through the catalyst bed under oxidation reaction conditions, so as to be mixed with the catalyst bed packed in the catalyst bed. Titanium-silicon molecular sieve contact reaction, the liquid mixture contains thioether, at least one oxidizing agent and optionally at least one solvent, wherein the method also includes when the conversion rate of the oxidizing agent and / or the selectivity of the target oxidation product decreases to a certain extent , increase the weight hourly space velocity of thioether until the conversion rate of the oxidant and / or the selectivity of the target oxidation product increase to meet the requirements. The method of the present invention can maintain the conversion rate of the oxidant and / or the selectivity of the target product in a relatively high range even if it operates continuously for a long period, thereby effectively prolonging the single-pass service life of the titanium-silicon molecular sieve as a catalyst and reducing the regeneration frequency. Extend the stable operation time of the device. The method of the invention is simple and easy to implement, and is beneficial to industrial production and application.

Description

technical field

[0001] The present invention relates to a kind of sulfide oxidation method. Background technique

[0002] Sulfoxides are important sulfur-containing compounds. For example, dimethyl sulfoxide (DMSO) is a sulfur-containing organic compound. It is a colorless and transparent liquid at room temperature. properties such as protons. Dimethyl sulfoxide is soluble in water, ethanol, acetone, ether and chloroform, is a highly polar inert solvent, and is widely used as a solvent and reaction reagent. Moreover, dimethyl sulfoxide has a high selective extraction ability and can be used as an extraction solvent for the separation of alkanes and aromatics. For example: dimethyl sulfoxide can be used for the extraction of aromatics or butadiene. In the polymerization reaction, it is used as a processing solvent and spinning solvent, as a synthetic solvent and spinning solvent of polyurethane, and as a synthetic solvent of polyamide, fluorochloroaniline, polyimide and pol...

Examples

Embodiment 4、12-15 and 17

[0087] Following examples 4, 12-15 and 17 adopt the following method to measure the activity of catalyst:

[0088] Catalyst, 36% by weight of ammonia water (as NH 3 meter), 30% by weight of hydrogen peroxide (as H 2 o 2 ), tert-butanol and cyclohexanone by mass ratio = 1:7.5:10:7.5:10 and then stirred and reacted at 80°C under atmospheric pressure for 2h, filtered the reactant, and analyzed the obtained liquid phase by gas chromatography The composition of the catalyst is analyzed, and the conversion rate of cyclohexanone is calculated by the following formula and used as the activity of the catalyst,

[0089] The conversion rate (%) of cyclohexanone=[(the molar amount of cyclohexanone added−the molar amount of unreacted cyclohexanone) / the molar amount of cyclohexanone added]×100%.

Embodiment 1

[0092] The catalyst (being a spherical catalyst with a volume average particle diameter of 500 μm, the content of titanium-silicon molecular sieve TS-1 in the catalyst is 85% by weight, the content of silicon oxide is 15% by weight, and the density is 0.79g / cm 3 ) is packed in a fixed-bed reactor to form a catalyst bed, wherein the number of the catalyst bed is 1 layer, and the aspect ratio of the catalyst bed is 10.

[0093] Dimethyl sulfide, hydrogen peroxide (provided in the form of 40% by weight hydrogen peroxide) as an oxidizing agent and acetone as a solvent were mixed to form a liquid mixture which was fed from the bottom into a fixed bed reactor in parallel flow over the catalyst bed. Among them, the initial molar ratio of dimethyl sulfide to hydrogen peroxide is 2:1, the initial molar ratio of dimethyl sulfide to acetone is 1:10, and the initial weight hourly space velocity of dimethyl sulfide is 0.5h -1 . The temperature in the catalyst bed was 35° C., and the pres...

Embodiment 2

[0099] Adopt the method identical with embodiment 1 to oxidize dimethyl sulfide, difference is, also send into the ammoniacal liquor (concentration is 25% by weight) in the fixed-bed reactor, to form by dimethyl sulfide, hydrogen peroxide and acetone The pH of the liquid mixture was adjusted to 7.0. Carry out the reaction for 580 hours, and the weight hourly space velocity of dimethyl sulfide at the end of the reaction is 2.1h -1 . The results obtained for 0.5 hours and 580 hours of reaction are listed in Table 1.

technical field

[0001] The present invention relates to a kind of sulfide oxidation method. Background technique

[0002] Sulfoxides are important sulfur-containing compounds. For example, dimethyl sulfoxide (DMSO) is a sulfur-containing organic compound. It is a colorless and transparent liquid at room temperature. properties such as protons. Dimethyl sulfoxide is soluble in water, ethanol, acetone, ether and chloroform, is a highly polar inert solvent, and is widely used as a solvent and reaction reagent. Moreover, dimethyl sulfoxide has a high selective extraction ability and can be used as an extraction solvent for the separation of alkanes and aromatics. For example: dimethyl sulfoxide can be used for the extraction of aromatics or butadiene. In the polymerization reaction, it is used as a processing solvent and spinning solvent, as a synthetic solvent and spinning solvent of polyurethane, and as a synthetic solvent of polyamide, fluorochloroaniline, polyimide and pol...

Examples

Embodiment 4、12-15 and 17

[0087] Following examples 4, 12-15 and 17 adopt the following method to measure the activity of catalyst:

[0088] Catalyst, 36% by weight of ammonia water (as NH 3 meter), 30% by weight of hydrogen peroxide (as H 2 o 2 ), tert-butanol and cyclohexanone by mass ratio = 1:7.5:10:7.5:10 and then stirred and reacted at 80°C under atmospheric pressure for 2h, filtered the reactant, and analyzed the obtained liquid phase by gas chromatography The composition of the catalyst is analyzed, and the conversion rate of cyclohexanone is calculated by the following formula and used as the activity of the catalyst,

[0089] The conversion rate (%) of cyclohexanone=[(the molar amount of cyclohexanone added−the molar amount of unreacted cyclohexanone) / the molar amount of cyclohexanone added]×100%.

Embodiment 1

[0092] The catalyst (being a spherical catalyst with a volume average particle diameter of 500 μm, the content of titanium-silicon molecular sieve TS-1 in the catalyst is 85% by weight, the content of silicon oxide is 15% by weight, and the density is 0.79g / cm 3 ) is packed in a fixed-bed reactor to form a catalyst bed, wherein the number of the catalyst bed is 1 layer, and the aspect ratio of the catalyst bed is 10.

[0093] Dimethyl sulfide, hydrogen peroxide (provided in the form of 40% by weight hydrogen peroxide) as an oxidizing agent and acetone as a solvent were mixed to form a liquid mixture which was fed from the bottom into a fixed bed reactor in parallel flow over the catalyst bed. Among them, the initial molar ratio of dimethyl sulfide to hydrogen peroxide is 2:1, the initial molar ratio of dimethyl sulfide to acetone is 1:10, and the initial weight hourly space velocity of dimethyl sulfide is 0.5h -1 . The temperature in the catalyst bed was 35° C., and the pres...

Embodiment 2

[0099] Adopt the method identical with embodiment 1 to oxidize dimethyl sulfide, difference is, also send into the ammoniacal liquor (concentration is 25% by weight) in the fixed-bed reactor, to form by dimethyl sulfide, hydrogen peroxide and acetone The pH of the liquid mixture was adjusted to 7.0. Carry out the reaction for 580 hours, and the weight hourly space velocity of dimethyl sulfide at the end of the reaction is 2.1h -1 . The results obtained for 0.5 hours and 580 hours of reaction are listed in Table 1.

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