CN111909054A - Production method of N, N-diethylhydroxylamine - Google Patents
Production method of N, N-diethylhydroxylamine Download PDFInfo
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- CN111909054A CN111909054A CN202010789166.1A CN202010789166A CN111909054A CN 111909054 A CN111909054 A CN 111909054A CN 202010789166 A CN202010789166 A CN 202010789166A CN 111909054 A CN111909054 A CN 111909054A
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- diethylhydroxylamine
- diethylamine
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- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C239/00—Compounds containing nitrogen-to-halogen bonds; Hydroxylamino compounds or ethers or esters thereof
- C07C239/08—Hydroxylamino compounds or their ethers or esters
- C07C239/10—Hydroxylamino compounds or their ethers or esters having nitrogen atoms of hydroxylamino groups further bound to carbon atoms of unsubstituted hydrocarbon radicals or of hydrocarbon radicals substituted by halogen atoms or by nitro or nitroso groups
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Abstract
The invention is suitable for the technical field of chemical production, and provides a production method of N, N-diethylhydroxylamine, which comprises the following steps: putting diethylamine, hydrogen peroxide and a titanium silicon oxygen catalyst into a solvent for oxidation reaction to obtain a crude product; carrying out negative pressure distillation on the crude product, and then carrying out suction filtration treatment to obtain filtrate; and (3) carrying out rectification separation treatment on the filtrate to obtain the N, N-diethylhydroxylamine. The production method provided by the embodiment of the invention has the advantages of simple process, high product conversion rate and higher production efficiency, and can obtain the N, N-diethylhydroxylamine product with the content of about 50 percent by carrying out catalytic oxidation reaction on diethylamine and hydrogen peroxide in an acetone solution by using a titanium-silicon-oxygen catalyst and then sequentially carrying out negative pressure distillation, suction filtration and rectification separation treatment, wherein the total conversion rate of the product can reach 90 percent.
Description
Technical Field
The invention belongs to the technical field of chemical production, and particularly relates to a production method of N, N-diethylhydroxylamine.
Background
N, N-diethylhydroxylamine is a medium-strength organic reducing agent, and can be used as polymerization inhibitor, antioxidant and stabilizing agent. Specifically, N, N-diethylhydroxylamine can be used as an antioxidant for unsaturated oils and resins, an environmental photochemical smog inhibitor, a corrosion inhibitor for boiler feed water and steam heat exchange equipment, a terminator for a styrene-butadiene emulsion polymerization process and the like.
Currently, the production process of N, N-diethylhydroxylamine comprises the following: secondary amines are oxidized with aqueous hydrogen peroxide in the presence of a catalyst of cadmium salt or zinc salt, or by oxidizing dialkylamines or triethylamine or the like with aqueous hydrogen peroxide in the presence of a titanium silicalite catalyst. However, the existing method for producing N, N-diethylhydroxylamine at least has the problems of more complex production process, lower total conversion rate of products and the like.
Disclosure of Invention
The embodiment of the invention aims to provide a production method of N, N-diethylhydroxylamine, aiming at solving the problems in the background technology.
The embodiment of the invention is realized in such a way that the production method of the N, N-diethylhydroxylamine comprises the following steps:
putting diethylamine, hydrogen peroxide and a titanium silicon oxygen catalyst into a solvent for oxidation reaction to obtain a crude product;
carrying out negative pressure distillation on the crude product, and then carrying out suction filtration treatment to obtain filtrate;
and (3) carrying out rectification separation treatment on the filtrate to obtain the N, N-diethylhydroxylamine.
The chemical reaction route of the production method is as follows:
as a preferred scheme of the embodiment of the present invention, the step of placing diethylamine, hydrogen peroxide and a titanium silicon oxygen catalyst in a solvent for oxidation reaction to obtain a crude product specifically comprises:
mixing diethylamine with a solvent, and then mixing the diethylamine with a titanium-silicon-oxygen catalyst to obtain a mixture;
and heating the mixture to 30-40 ℃, and then dropwise adding hydrogen peroxide into the mixture for oxidation reaction to obtain a crude product.
In another preferable embodiment of the invention, the mass ratio of the diethylamine to the hydrogen peroxide is (0.35-0.55): 1.
In another preferred embodiment of the present invention, the mass ratio of the diethylamine to the titanium-silicon-oxygen catalyst is (0.09-0.13): 1000.
In another preferable embodiment of the invention, the mass ratio of the diethylamine to the solvent is (0.015-0.02): 1.
As another preferred aspect of the embodiments of the present invention, the solvent is acetone.
As another preferable mode of the embodiment of the present invention, in the step, the degree of vacuum of the negative pressure distillation is not less than 0.07 MPa.
In another preferable scheme of the embodiment of the invention, in the step, the temperature of the negative pressure distillation is 50-60 ℃.
As another preferable scheme of the embodiment of the invention, in the step, the vacuum degree of the rectification separation treatment is not lower than 0.07 MPa.
The production method of N, N-diethylhydroxylamine provided by the embodiment of the invention has the advantages of simple process, high product conversion rate and higher production efficiency, and N, N-diethylhydroxylamine with the content of about 50% can be obtained by carrying out catalytic oxidation reaction on diethylamine and hydrogen peroxide in an acetone solution by using a titanium silicon oxide catalyst, and then sequentially carrying out negative pressure distillation, suction filtration and rectification separation treatment, wherein the total conversion rate of the product can reach 90%.
Drawings
FIG. 1 is a process flow diagram of a method for producing N, N-diethylhydroxylamine according to an embodiment of the present invention.
FIG. 2 is a diagram showing the mass balance analysis of a process for producing N, N-diethylhydroxylamine according to example 1 of the present invention (unit: kg/lot).
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1
As shown in FIG. 1, this example provides a process for the production of N, N-diethylhydroxylamine comprising the steps of:
s1, pumping 1523.66kg of diethylamine into a metering tank by a delivery pump for metering, placing the metered diethylamine into an oxidation kettle at a high position, sequentially adding 28kg of acetone solvent and 0.17kg of titanium-silicon-oxygen catalyst into the oxidation kettle, and stirring in a sealed manner; next, 2011.37kg of 35% hydrogen peroxide solution was pumped into a high-level tank by a delivery pump; then, heating the oxidation kettle to 30 ℃ through jacket steam, closing the steam, beginning to dropwise add hydrogen peroxide in the head tank into the oxidation kettle for 4 hours, and preserving heat for 1 hour after dropwise adding is finished so as to carry out closed normal-pressure oxidation reaction; after the reaction is finished, cooling to below 30 ℃ by jacket cooling water to obtain a crude product for later use.
S2, pumping the crude product in the oxidation kettle into a distillation recovery kettle with the vacuum degree of 0.07MPa through a vacuum pump, and slowly raising the temperature of the distillation recovery kettle to 50 ℃ to carry out negative pressure distillation; and condensing the distilled diethylamine and acetone by a four-stage brine condenser, then feeding the condensed diethylamine and acetone into a receiver for next batch application, feeding the residual liquid into a filter cartridge filter, and carrying out vacuum filtration to obtain the catalyst, thus obtaining the filtrate.
S3, pumping the filtrate into a rectifying still by a pump, and starting a vacuum pump to maintain the vacuum degree of the rectifying still at 0.07 Mpa; and then, starting jacket steam to heat until filtrate is gasified, condensing four-stage brine (below 10 ℃) and then feeding the condensate into a receiving tank, absorbing uncondensed tail gas by a deionized water spray tower, and mixing the uncondensed tail gas with a condensed product to obtain the product containing the N, N-diethylhydroxylamine.
Example 2
As shown in FIG. 1, this example provides a process for the production of N, N-diethylhydroxylamine comprising the steps of:
s1, pumping 1523.66kg of diethylamine into a metering tank by a delivery pump for metering, placing the metered diethylamine into an oxidation kettle at a high position, sequentially adding 22.85kg of acetone solvent and 0.14kg of titanium-silicon-oxygen catalyst into the oxidation kettle, and stirring in a sealed manner; next, 1523.66kg of 35% hydrogen peroxide solution was pumped into a high-level tank by a delivery pump; then, heating the oxidation kettle to 40 ℃ through jacket steam, closing the steam, beginning to dropwise add hydrogen peroxide in the head tank into the oxidation kettle for 4 hours, and preserving heat for 1 hour after dropwise adding is finished so as to carry out closed normal-pressure oxidation reaction; after the reaction is finished, cooling to below 30 ℃ by jacket cooling water to obtain a crude product for later use.
S2, pumping the crude product in the oxidation kettle into a distillation recovery kettle with the vacuum degree of 0.07MPa through a vacuum pump, and slowly raising the temperature of the distillation recovery kettle to 60 ℃ to carry out negative pressure distillation; and condensing the distilled diethylamine and acetone by a four-stage brine condenser, then feeding the condensed diethylamine and acetone into a receiver for next batch application, feeding the residual liquid into a filter cartridge filter, and carrying out vacuum filtration to obtain the catalyst, thus obtaining the filtrate.
S3, pumping the filtrate into a rectifying still by a pump, and starting a vacuum pump to maintain the vacuum degree of the rectifying still at 0.07 Mpa; and then, starting jacket steam to heat until filtrate is gasified, condensing four-stage brine (below 10 ℃) and then feeding the condensate into a receiving tank, absorbing uncondensed tail gas by a deionized water spray tower, and mixing the uncondensed tail gas with a condensed product to obtain the product containing the N, N-diethylhydroxylamine.
Example 3
As shown in FIG. 1, this example provides a process for the production of N, N-diethylhydroxylamine comprising the steps of:
s1, pumping 1523.66kg of diethylamine into a metering tank by a delivery pump for metering, placing the metered diethylamine into an oxidation kettle at a high position, sequentially adding 30.47kg of acetone solvent and 0.2kg of titanium-silicon-oxygen catalyst into the oxidation kettle, and carrying out closed stirring; next, 2394.32kg of 35% hydrogen peroxide solution was pumped into a high-level tank by a delivery pump; then, heating the oxidation kettle to 35 ℃ through jacket steam, closing the steam, beginning to dropwise add hydrogen peroxide in the head tank into the oxidation kettle for 4 hours, and preserving heat for 1 hour after dropwise adding is finished so as to carry out closed normal-pressure oxidation reaction; after the reaction is finished, cooling to below 30 ℃ by jacket cooling water to obtain a crude product for later use.
S2, pumping the crude product in the oxidation kettle into a distillation recovery kettle with the vacuum degree of 0.07MPa through a vacuum pump, and slowly raising the temperature of the distillation recovery kettle to 56 ℃ to carry out negative pressure distillation; and condensing the distilled diethylamine and acetone by a four-stage brine condenser, then feeding the condensed diethylamine and acetone into a receiver for next batch application, feeding the residual liquid into a filter cartridge filter, and carrying out vacuum filtration to obtain the catalyst, thus obtaining the filtrate.
S3, pumping the filtrate into a rectifying still by a pump, and starting a vacuum pump to maintain the vacuum degree of the rectifying still at 0.07 Mpa; and then, starting jacket steam to heat until filtrate is gasified, condensing four-stage brine (below 10 ℃) and then feeding the condensate into a receiving tank, absorbing uncondensed tail gas by a deionized water spray tower, and mixing the uncondensed tail gas with a condensed product to obtain the product containing the N, N-diethylhydroxylamine.
Example 4
As shown in FIG. 1, this example provides a process for the production of N, N-diethylhydroxylamine comprising the steps of:
s1, pumping 1523.66kg of diethylamine into a metering tank by a delivery pump for metering, placing the metered diethylamine into an oxidation kettle at a high position, sequentially adding 26kg of acetone solvent and 0.18kg of titanium-silicon-oxygen catalyst into the oxidation kettle, and stirring in a sealed manner; then, 2000kg of 35% hydrogen peroxide solution is pumped into a high-level tank by a delivery pump; then, heating the oxidation kettle to 35 ℃ through jacket steam, closing the steam, beginning to dropwise add hydrogen peroxide in the head tank into the oxidation kettle for 4 hours, and preserving heat for 1 hour after dropwise adding is finished so as to carry out closed normal-pressure oxidation reaction; after the reaction is finished, cooling to below 30 ℃ by jacket cooling water to obtain a crude product for later use.
S2, pumping the crude product in the oxidation kettle into a distillation recovery kettle with the vacuum degree of 0.08MPa through a vacuum pump, and slowly raising the temperature of the distillation recovery kettle to 57 ℃ to carry out negative pressure distillation; and condensing the distilled diethylamine and acetone by a four-stage brine condenser, then feeding the condensed diethylamine and acetone into a receiver for next batch application, feeding the residual liquid into a filter cartridge filter, and carrying out vacuum filtration to obtain the catalyst, thus obtaining the filtrate.
S3, pumping the filtrate into a rectifying still by a pump, and starting a vacuum pump to maintain the vacuum degree of the rectifying still at 0.08 Mpa; and then, starting jacket steam to heat until filtrate is gasified, condensing four-stage brine (below 10 ℃) and then feeding the condensate into a receiving tank, absorbing uncondensed tail gas by a deionized water spray tower, and mixing the uncondensed tail gas with a condensed product to obtain the product containing the N, N-diethylhydroxylamine.
Example 5
As shown in FIG. 1, this example provides a process for the production of N, N-diethylhydroxylamine comprising the steps of:
s1, pumping 1523.66kg of diethylamine into a metering tank by a delivery pump for metering, placing the metered diethylamine into an oxidation kettle at a high position, sequentially adding 25kg of acetone solvent and 0.16kg of titanium-silicon-oxygen catalyst into the oxidation kettle, and stirring in a sealed manner; then, 2118kg of 35% hydrogen peroxide solution is pumped into a high-level tank by a delivery pump; then, heating the oxidation kettle to 37 ℃ through jacket steam, closing the steam, beginning to dropwise add hydrogen peroxide in the head tank into the oxidation kettle for 4 hours, and preserving heat for 1 hour after dropwise adding is finished so as to carry out closed normal-pressure oxidation reaction; after the reaction is finished, cooling to below 30 ℃ by jacket cooling water to obtain a crude product for later use.
S2, pumping the crude product in the oxidation kettle into a distillation recovery kettle with the vacuum degree of 0.09MPa through a vacuum pump, and slowly raising the temperature of the distillation recovery kettle to 58 ℃ to carry out negative pressure distillation; and condensing the distilled diethylamine and acetone by a four-stage brine condenser, then feeding the condensed diethylamine and acetone into a receiver for next batch application, feeding the residual liquid into a filter cartridge filter, and carrying out vacuum filtration to obtain the catalyst, thus obtaining the filtrate.
S3, pumping the filtrate into a rectifying still by a pump, and starting a vacuum pump to maintain the vacuum degree of the rectifying still at 0.09 Mpa; and then, starting jacket steam to heat until filtrate is gasified, condensing four-stage brine (below 10 ℃) and then feeding the condensate into a receiving tank, absorbing uncondensed tail gas by a deionized water spray tower, and mixing the uncondensed tail gas with a condensed product to obtain the product containing the N, N-diethylhydroxylamine.
Wherein, the production analysis of the production method provided by the above embodiment is shown in figure 1, and G in figure 11-1The method is a negative pressure distillation noncondensable gas, and the main pollutants are oxygen, diethylamine and acetone; g1-2The waste gas is filtered, and the main pollutants are acetone and diethylamine; g1-3The main pollutants are N, N-diethylhydroxylamine, acetone and diethylamine; s1-1Belongs to dangerous solid waste for rectifying residue.
In addition, the above-mentioned production method provided in example 1 gave a product containing 50% of N, N-diethylhydroxylamine, and the material balance analysis thereof is shown in FIG. 2 and Table 1 below. Wherein the conversion of the product of the production process is 90% calculated on diethylamine.
TABLE 1
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (9)
1. A production method of N, N-diethylhydroxylamine is characterized by comprising the following steps:
putting diethylamine, hydrogen peroxide and a titanium silicon oxygen catalyst into a solvent for oxidation reaction to obtain a crude product;
carrying out negative pressure distillation on the crude product, and then carrying out suction filtration treatment to obtain filtrate;
and (3) carrying out rectification separation treatment on the filtrate to obtain the N, N-diethylhydroxylamine.
2. The production method of N, N-diethylhydroxylamine according to claim 1, wherein the step of placing diethylamine, hydrogen peroxide and titanium silicon oxygen catalyst in a solvent for oxidation reaction to obtain a crude product comprises:
mixing diethylamine with a solvent, and then mixing the diethylamine with a titanium-silicon-oxygen catalyst to obtain a mixture;
and heating the mixture to 30-40 ℃, and then dropwise adding hydrogen peroxide into the mixture for oxidation reaction to obtain a crude product.
3. The production method of N, N-diethylhydroxylamine according to claim 1 or 2, wherein the mass ratio of diethylamine to hydrogen peroxide is (0.35-0.55): 1.
4. The method for producing N, N-diethylhydroxylamine as claimed in claim 1 or 2, wherein the mass ratio of diethylamine to titanium-silicon-oxygen catalyst is (0.09-0.13): 1000.
5. The method for producing N, N-diethylhydroxylamine as claimed in claim 1 or 2, wherein the mass ratio of the diethylamine to the solvent is (0.015 to 0.02): 1.
6. A process for the production of N, N-diethylhydroxylamine as claimed in claim 1 or 2 wherein the solvent is acetone.
7. A process for producing N, N-diethylhydroxylamine as claimed in claim 1, wherein in said step, the degree of vacuum of the negative pressure distillation is not less than 0.07 MPa.
8. A process for producing N, N-diethylhydroxylamine as claimed in claim 7, wherein the temperature of the negative pressure distillation in the step is 50 to 60 ℃.
9. The process according to claim 1, wherein the degree of vacuum in the rectification separation treatment is not less than 0.07 MPa.
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| CN202010789166.1A CN111909054A (en) | 2020-08-07 | 2020-08-07 | Production method of N, N-diethylhydroxylamine |
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| CN202010789166.1A CN111909054A (en) | 2020-08-07 | 2020-08-07 | Production method of N, N-diethylhydroxylamine |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022156391A1 (en) * | 2021-01-20 | 2022-07-28 | 济宁学院 | Preparation method for core-shell titanium-silicon molecular sieve coated zinc-cadmium alloy particle catalyst, and method for preparing n,n-diethylhydroxylamine by using core-shell titanium-silicon molecular sieve coated zinc-cadmium alloy particle catalyst |
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| GB931582A (en) * | 1961-03-30 | 1963-07-17 | Pennsalt Chemicals Corp | Process for the preparation of dimethylhydroxylamine |
| US4918194A (en) * | 1987-10-29 | 1990-04-17 | Montedipe S.P.A. | Process for the synthesis of a N,N-dialkyl-hydroxylamine |
| US6074622A (en) * | 1996-10-11 | 2000-06-13 | Elf Atochem S.A. | Catalyst based on titanosilicalites and process for producing N,N-disubstituted hydroxylamine |
| CN105152962A (en) * | 2015-09-30 | 2015-12-16 | 淄博亿丰中铁高分子材料有限公司 | Preparation method of N-isopropylhydroxylamine oxalate |
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2020
- 2020-08-07 CN CN202010789166.1A patent/CN111909054A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB931582A (en) * | 1961-03-30 | 1963-07-17 | Pennsalt Chemicals Corp | Process for the preparation of dimethylhydroxylamine |
| US4918194A (en) * | 1987-10-29 | 1990-04-17 | Montedipe S.P.A. | Process for the synthesis of a N,N-dialkyl-hydroxylamine |
| US6074622A (en) * | 1996-10-11 | 2000-06-13 | Elf Atochem S.A. | Catalyst based on titanosilicalites and process for producing N,N-disubstituted hydroxylamine |
| CN105152962A (en) * | 2015-09-30 | 2015-12-16 | 淄博亿丰中铁高分子材料有限公司 | Preparation method of N-isopropylhydroxylamine oxalate |
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| 杨世刚等: "二乙胺羟基化合成二乙基羟胺", 《云南化工》 * |
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| 邓秀娟等: "TS-1/H2O2体系催化二乙胺氧化竞争反应", 《催化学报》 * |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022156391A1 (en) * | 2021-01-20 | 2022-07-28 | 济宁学院 | Preparation method for core-shell titanium-silicon molecular sieve coated zinc-cadmium alloy particle catalyst, and method for preparing n,n-diethylhydroxylamine by using core-shell titanium-silicon molecular sieve coated zinc-cadmium alloy particle catalyst |
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Application publication date: 20201110 |