阅读说明：本技术 双氯磺酰亚胺的生产工艺 (Production process of bis (chlorosulfonyl) imide ) 是由 张泰铭 李光辉 孙庆民 王军 孙丰春 孙健 杨建玲 薛居强 王永 于 2021-09-14 设计创作，主要内容包括：本发明涉及双氯磺酰亚胺生产技术领域,具体涉及一种双氯磺酰亚胺的生产工艺。所述的双氯磺酰亚胺的生产工艺,包括以下步骤：将氨基磺酸、氯化亚砜加入至反应釜至固体全部溶解,然后将三氧化硫匀速加入反应釜中,三氧化硫加完后,升温至90-120℃继续反应5-10h,恢复至常压,开启冷凝器的冷凝液接出阀,继续反应1-3h,至无冷凝液从冷凝器中流出,进行减压精馏,得到目标产物双氯磺酰亚胺。本发明相较于原氯磺酸法工艺,减少氯化氢废气量1/3,并且本工艺二氧化硫尾气可回收套用至氯化亚砜生产装置,进一步减少了三废产量,属于符合绿色化工产业发展要求的创新型工艺。(The invention relates to the technical field of production of bischlorosulfonimide, in particular to a production process of bischlorosulfonimide. The production process of the bis (chlorosulfonyl) imide comprises the following steps: adding sulfamic acid and thionyl chloride into a reaction kettle until the solid is completely dissolved, then adding sulfur trioxide into the reaction kettle at a constant speed, heating to 90-120 ℃ after the sulfur trioxide is added, continuing to react for 5-10h, recovering to normal pressure, opening a condensate liquid outlet valve of a condenser, continuing to react for 1-3h until no condensate liquid flows out of the condenser, and performing reduced pressure rectification to obtain the target product, namely the bischlorosulfonimide. Compared with the original chlorosulfonic acid process, the method reduces 1/3 of the waste gas amount of hydrogen chloride, and the tail gas of sulfur dioxide can be recycled and applied to a thionyl chloride production device, so that the yield of three wastes is further reduced, and the method belongs to an innovative process meeting the development requirements of green chemical industry.)

1. A production process of bis (chlorosulfonyl) imide is characterized by comprising the following steps: sulfamic acid, thionyl chloride and sulfur trioxide are used as raw materials, and the raw materials are reacted at the temperature of 40-70 ℃ and then at the temperature of 90-120 ℃ to prepare the bis-chlorosulfonyl imine.

2. The process for the production of bis-chlorosulfonyl imide according to claim 1, wherein: the method comprises the following steps:

(1) adding sulfamic acid and thionyl chloride into a reaction kettle, and starting a stirring and condenser reflux device until all solids are dissolved;

(2) then adding sulfur trioxide into the reaction kettle at a constant speed at the temperature of 40-70 ℃, after the addition of the sulfur trioxide is finished, heating to 90-120 ℃, continuing to react for 5-10h, recovering to the normal pressure, opening a condensate receiving valve of a condenser, continuing to react for 1-3h until no condensate flows out of the condenser, and performing reduced pressure rectification to obtain the target product, namely the bischlorosulfonimide.

3. The process for the production of bis-chlorosulfonyl imide according to claim 1 or 2, wherein: the molar ratio of sulfamic acid to sulfur trioxide to thionyl chloride is 1:1 (2-2.5).

4. The process for the production of bis-chlorosulfonyl imide according to claim 2, wherein: in the step (1), the pressure in the reaction kettle is controlled to be 0.1-0.7MPa, and the temperature is controlled to be 40-70 ℃.

5. The process for the production of bis-chlorosulfonyl imide according to claim 2, wherein: in the step (2), the adding time of sulfur trioxide is controlled to be 1-6 h.

6. The process for the production of bis-chlorosulfonyl imide according to claim 2, wherein: in the step (2), the condensate is excessive thionyl chloride, and is recycled after flowing out of the condenser.

7. The process for the production of bis-chlorosulfonyl imide according to claim 2, wherein: in the step (2), the pressure of the reduced pressure distillation is 5-10 mmHg, and the temperature of the target product of the bischlorosulfonimide distillate is 90-105 ℃.

8. The process for the production of bis-chlorosulfonyl imide according to claim 2, wherein: in the step (2), sulfur dioxide and hydrogen chloride tail gas generated in the reaction process are absorbed by a multi-stage absorption tower to obtain a byproduct hydrochloric acid aqueous solution and sulfur dioxide gas, and the sulfur dioxide is recycled and applied to the thionyl chloride production process.

Technical Field

The invention relates to the technical field of production of bischlorosulfonimide, in particular to a production process of bischlorosulfonimide.

Background

With the continuous increase of market demand of novel electrolyte bis (fluorosulfonyl imide) of lithium batteries in recent years, the production process of the raw material bis (chlorosulfonyl imide) is more and more important, and the further production of bis (fluorosulfonyl imide) by fluorine-chlorine halogen exchange of the bis (chlorosulfonyl imide) is the most valuable production method at present.

The mainstream production process of the bis (chlorosulfonyl) imide comprises two types: the method is characterized in that sulfamic acid, thionyl chloride and chlorosulfonic acid are used as raw materials to synthesize the dichlorosulfonimide, and the reaction process is as follows:

for example, patent CN101747242B discloses a method for preparing bis (fluorosulfonyl) imide, which comprises a synthesis process of bis (chlorosulfonyl) imide, wherein sulfamic acid, thionyl chloride and chlorosulfonic acid are used as raw materials, and the raw materials are reacted at a high temperature of 110-130 ℃ for 20-24 hours, and then rectified to obtain bis (chlorosulfonyl) imide, the reaction equation is as follows. And the process has long reaction period and high reaction temperature, so that the energy consumption is high, the side reactions are more, and the optimization and the upgrade are urgently needed due to various problems.

The other one is to synthesize the dichlorosulfonimide by taking chlorosulfonic acid and chlorosulfonyl isocyanate as raw materials, and the reaction flow is as follows:

for example, patent CN1606447288B discloses a method for preparing lithium bis (fluorosulfonyl) imide, which comprises a synthesis process of bis (chlorosulfonyl) imide. Chlorosulfonic acid and chlorosulfonyl isocyanate are used as raw materials, and react at a high temperature of 120-140 ℃ under the action of a catalyst to obtain the dichlorosulfimide through distillation, the reaction equation is as follows, the process has the advantages that no by-product gas of sulfur dioxide and hydrogen chloride exists, the atom utilization rate is high, but the problem is also obvious, the chlorosulfonyl isocyanate raw material is prepared from cyanogen chloride and sulfur trioxide, the cyanogen chloride is extremely high in toxicity and price, the use cost of the chlorosulfonyl isocyanate raw material is too high, the market profit space of the dichlorosulfimide is reduced, and the process is difficult to use on a large scale.

In summary, the existing production process of bis (chlorosulfonyl) imide has the problems of large amount of three wastes, more side reactions, high raw material cost and the like, and with the development of the lithium battery industry and bis (fluorosulfonyl) imide electrolyte, higher requirements are also provided for the product quality of bis (chlorosulfonyl) imide, and a more advantageous novel production process needs to be developed to solve the problems.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: compared with the original chlorosulfonic acid method process, the production process of the bischlorosulfonimide is provided, the amount of the hydrogen chloride waste gas is reduced by 1/3, and the sulfur dioxide tail gas in the process can be recycled and reused in a thionyl chloride production device, so that the yield of three wastes is further reduced, and the process belongs to an innovative process meeting the development requirements of the green chemical industry.

The production process of the bis (chlorosulfonyl) imide takes sulfamic acid, thionyl chloride and sulfur trioxide as raw materials, and the bis (chlorosulfonyl) imide is prepared by firstly reacting at the temperature of 40-70 ℃ and then reacting at the temperature of 90-120 ℃.

The production process of the bis (chlorosulfonyl) imide comprises the following steps:

(1) adding sulfamic acid and thionyl chloride into a reaction kettle, and starting a stirring and condenser reflux device until all solids are dissolved;

(2) then adding sulfur trioxide into the reaction kettle at a constant speed at the temperature of 40-70 ℃, after the addition of the sulfur trioxide is finished, heating to 90-120 ℃, continuing to react for 5-10h, recovering to the normal pressure, opening a condensate receiving valve of a condenser, continuing to react for 1-3h until no condensate flows out of the condenser, and performing reduced pressure rectification to obtain the target product, namely the bischlorosulfonimide.

Wherein the molar ratio of sulfamic acid to sulfur trioxide to thionyl chloride is 1:1 (2-2.5);

in the step (1), the pressure in the reaction kettle is controlled to be 0.1-0.7MPa, and the temperature is controlled to be 40-70 ℃.

In the step (2), the adding time of sulfur trioxide is controlled to be 1-6 h.

In the step (2), the condensate is excessive thionyl chloride, and is recycled after flowing out of the condenser.

In the step (2), the pressure of the reduced pressure distillation is 5-10 mmHg, and the temperature of the target product of the bischlorosulfonimide distillate is 90-105 ℃.

In the step (2), sulfur dioxide and hydrogen chloride tail gas generated in the reaction process are absorbed by a multi-stage absorption tower to obtain a byproduct hydrochloric acid aqueous solution and sulfur dioxide gas, and the sulfur dioxide is recycled and applied to the thionyl chloride production process.

Compared with the prior art, the invention has the following beneficial effects:

(1) compared with the traditional process, the invention does not use chlorosulfonic acid with higher cost, innovatively develops the sulfur trioxide process, reduces the cost of raw materials, improves the reaction activity, improves the utilization rate of the raw materials and shortens the reaction period;

(2) compared with the traditional chlorosulfonic acid process, the sulfur trioxide route process reduces 1/3 byproduct hydrogen chloride gas, and because the additional value of the byproduct hydrogen chloride is lower and the treatment cost is high, the process greatly reduces the treatment pressure of the production tail gas, and belongs to a cleaner and more economic new process;

(3) according to the invention, on the basis of adopting a sulfur trioxide process, reaction process parameters are further optimized and divided into two reaction stages of low temperature and high temperature, compared with the high temperature reaction of the traditional process, the probability of side reaction of the process is greatly reduced, the purity of the product obtained after rectification is higher and can reach more than 99.8%, and the method is suitable for producing the lithium bis (fluorosulfonyl) imide for the downstream lithium battery.

Detailed Description

The present invention is further described in the following examples, which should not be construed as limiting the scope of the invention, but rather as providing those skilled in the art with the benefit of the present disclosure with additional inventive concepts and features described herein.

Example 1

97.1g (1mol) of sulfamic acid and 273.7g (2.3mol) of thionyl chloride are added into a reaction kettle, stirring is started, a condenser reflux device is started, the temperature is controlled to be 55 ℃, the pressure of a back pressure valve is set to be 0.4MPa, after all solids are dissolved, 80g (1mol) of sulfur trioxide is added into the reaction kettle at a constant speed within 3h, after the sulfur trioxide is added, the temperature is increased to 110 ℃, the reaction is continued for 7.5h, the normal pressure is recovered, a condensate liquid outlet valve of the condenser is started, the reaction is continued for 2h, no condensate liquid flows out of the condenser, reduced pressure rectification is started, and 90-105 ℃ fraction is collected, so that 212.4g of the bischlorosulfonimide liquid is obtained, the reaction yield is 99.1%, and the product purity is 99.9%.

Example 2

Adding 97.1g (1mol) of sulfamic acid and 238g (2.0mol) of thionyl chloride into a reaction kettle, starting stirring, starting a condenser reflux device, controlling the temperature to be 40 ℃, setting the pressure of a back pressure valve to be 0.1MPa, adding 80g (1mol) of sulfur trioxide into the reaction kettle at a constant speed within 1h after all solids are dissolved, heating to 90 ℃ after the sulfur trioxide is added, continuing to react for 5h, recovering to the normal pressure, starting a condensate take-off valve of the condenser, continuing to react for 1h until no condensate flows out of the condenser, starting reduced pressure rectification, collecting 90-105 ℃ fractions, and obtaining 205.5g of the bischlorosulfonimide liquid of the invention, wherein the reaction yield is 96.0%, and the product purity is 99.8%.

Example 3

Adding 97.1g (1mol) of sulfamic acid and 297.5g (2.5mol) of thionyl chloride into a reaction kettle, starting stirring, starting a condenser reflux device, controlling the temperature to be 70 ℃, setting the pressure of a back pressure valve to be 0.7MPa, after all solids are dissolved, adding 80g (1mol) of sulfur trioxide into the reaction kettle at a constant speed within 6h, heating to 120 ℃ after the sulfur trioxide is added, continuing to react for 10h, recovering to the normal pressure, starting a condensate take-off valve of the condenser, continuing to react for 3h until no condensate flows out of the condenser, starting reduced pressure rectification, collecting 90-105 ℃ fraction, and obtaining 211.0g of the bischlorosulfonimide liquid, wherein the reaction yield is 98.5%, and the product purity is 99.9%.

Example 4

97.1g (1mol) of sulfamic acid and 273.7g (2.3mol) of thionyl chloride are added into a reaction kettle, stirring is started, a condenser reflux device is started, the temperature is controlled to be 70 ℃, the pressure of a back pressure valve is set to be 0.7MPa, after all solids are dissolved, 80g (1mol) of sulfur trioxide is added into the reaction kettle at a constant speed within 1h, after the sulfur trioxide is added, the temperature is increased to 110 ℃, the reaction is continued for 10h, the normal pressure is recovered, a condensate take-off valve of the condenser is started, the reaction is continued for 1h, no condensate flows out of the condenser, reduced pressure rectification is started, and 90-105 ℃ fractions are collected, so that 210.0g of the bischlorosulfonimide liquid of the product is obtained, the reaction yield is 98%, and the product purity is 99.9%.

Comparative example 1

Adding 97.1g (1mol) of sulfamic acid, 273.7g (2.3mol) of thionyl chloride and 117g (1mol) of chlorosulfonic acid into a reaction kettle, starting stirring, starting a condenser reflux device, controlling the temperature to be 130 ℃, reacting for 24 hours, distilling at normal pressure to remove excessive thionyl chloride, and carrying out reduced pressure distillation to collect 90-105 ℃ fraction to obtain 192.2g of bischlorosulfonimide liquid, wherein the reaction yield is 88% and the product purity is 98.1%.

Comparative example 2

Adding 97.1g (1mol) of sulfamic acid, 273.7g (2.3mol) of thionyl chloride and 80g (1mol) of sulfur trioxide into a reaction kettle, starting stirring, starting a condenser reflux device, controlling the temperature to be 130 ℃, reacting for 24 hours, distilling at normal pressure to remove excessive thionyl chloride, and collecting 90-105 ℃ fraction by reduced pressure distillation to obtain 201g of bischlorosulfimide liquid, wherein the reaction yield is 92.0 percent and the product purity is 98.0 percent.

The purity of the products of examples 1 to 4 and comparative examples 1 to 2 was checked by means of potentiometric titration, according to the following analytical methods:

(1) and (3) measuring N: adding water into a sample, fully hydrolyzing, titrating by using a sodium nitrite solution, and taking starch potassium iodide as an indicator;

(2) and (3) measuring Cl: and (3) fully hydrolyzing the sample by using glacial alkaline water, and measuring the content of chloride ions by potentiometric titration by using silver nitrate as a titration solution.

(3) If Cl%/N% >2, calculating the purity of the sample by N%; if Cl%/N% < 2, the sample purity is calculated as Cl%.

The technical advantage ratios of examples 1 to 4 and comparative examples 1 to 2 are shown in table 1.

TABLE 1 comparison of technical advantages of examples 1-4 and comparative examples 1-2

Numbering	Reaction temperature of	Reaction time, h	Reaction yield%	Product purity%	Amount of 1mol of three wastes of product, g
						Example 1	55、110	12.5	99.1	99.9	83.7
Example 2	40、90	7	96.0	99.8	90.6
						Example 3	70、120	19	98.5	99.9	85.1
Example 4	70、110	12	98.0	99.9	86.1
						Comparative example 1	130	24	88.0	98.0	140.9
Comparative example 2	130	24	92.0	98.1	100.1

As can be seen from Table 1, in comparative example 1, sulfamic acid, thionyl chloride and chlorosulfonic acid are used as raw materials to synthesize the bis-chlorosulfonyl imide at high temperature, and compared with the process disclosed by the invention, the process has the advantages of milder reaction conditions, short reaction period, high product yield, high product purity and small three wastes.