阅读说明：本技术 一种混酸溶液中硝酸的去除方法 (Method for removing nitric acid in mixed acid solution ) 是由 谢丹 陈伟 于 2021-08-17 设计创作，主要内容包括：本发明公开了一种混酸溶液中硝酸的去除方法,所述去除方法包括如下步骤：将混酸溶液升温,其中,混酸溶液为硫酸和硝酸的混合溶液；向混酸溶液中加入尿素,直至无气泡产生；将混酸溶液进行降温、收集硫酸；本发明上述去除方法能够高效去除混酸溶液中的硝酸,去除效率较高；此外,该去除方法能够实现硫酸的回收利用,提高资源利用率,并能够减少直接排放造成的环境污染。(The invention discloses a method for removing nitric acid in a mixed acid solution, which comprises the following steps: heating a mixed acid solution, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid; adding urea into the mixed acid solution until no bubbles are generated; cooling the mixed acid solution and collecting sulfuric acid; the removal method can efficiently remove the nitric acid in the mixed acid solution, and has high removal efficiency; in addition, the removal method can realize the recycling of the sulfuric acid, improve the resource utilization rate and reduce the environmental pollution caused by direct discharge.)

1. A method for removing nitric acid in mixed acid solution is characterized by comprising the following steps:

(a) heating a mixed acid solution, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid;

(b) adding urea into the mixed acid solution until no bubbles are generated;

(c) and cooling the mixed acid solution and collecting sulfuric acid.

2. The method for removing nitric acid from a mixed acid solution according to claim 1, wherein the temperature of the mixed acid solution is raised to 30 to 50 ℃.

3. The method for removing nitric acid from a mixed acid solution according to claim 1 or 2, wherein the temperature of the mixed acid solution is raised to 42 ℃.

4. The method for removing nitric acid from a mixed acid solution according to claim 1, wherein the temperature is reduced to room temperature.

5. The method for removing nitric acid from a mixed acid solution according to claim 1, wherein urea is added to the mixed acid solution under stirring.

6. The method for removing nitric acid from a mixed acid solution according to claim 5, wherein the stirring speed is 10-50 r/min.

7. The method for removing nitric acid from a mixed acid solution according to claim 1, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid generated in chemical production.

Technical Field

The invention relates to the technical field of mixed acid treatment, in particular to a method for removing nitric acid in a mixed acid solution.

Background

With the development of industrialization, the amount of mixed acid generated in chemical production is huge, and the amount of nitric acid cannot be accurately mastered due to different nitric acid contents in the mixed acid, so that the mixed acid solution cannot be directly applied, and a large amount of the mixed acid solution can be wasted; in addition, if the mixed acid solution is directly discharged, not only resources are wasted, but also environmental pollution is brought, and the environmental burden is increased.

At present, a method for removing nitric acid and recovering sulfuric acid from a mixed acid solution in a better way does not exist in the prior art, so that a process for removing nitric acid from mixed acid is urgently needed, and the environmental protection pressure of enterprises is reduced.

Disclosure of Invention

The invention aims to provide a method for removing nitric acid in a mixed acid solution, which can efficiently remove the nitric acid in the mixed acid solution and has higher removal efficiency; in addition, the removal method can realize the recycling of the sulfuric acid, improve the resource utilization rate and reduce the environmental pollution caused by direct discharge.

In order to achieve the above purpose of the present invention, the following technical solutions are adopted:

the first aspect of the invention provides a method for removing nitric acid from a mixed acid solution, which comprises the following steps:

(a) heating a mixed acid solution, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid;

(b) adding urea into the mixed acid solution until no bubbles are generated;

(c) and cooling the mixed acid solution and collecting sulfuric acid.

Preferably, the temperature of the mixed acid solution is raised to 30-50 ℃.

Preferably, the mixed acid solution is heated to 42 ℃.

Preferably, the temperature is reduced to room temperature.

Preferably, urea is added to the mixed acid solution under stirring.

Preferably, the stirring speed is 10-50 r/min.

Preferably, the mixed acid solution is a mixed solution of sulfuric acid and nitric acid generated in chemical production.

Compared with the prior art, the invention has the beneficial effects that at least:

the removal method can efficiently remove the nitric acid in the mixed acid solution, and has high removal efficiency; in addition, the removal method can realize the recycling of the sulfuric acid, improve the resource utilization rate and reduce the environmental pollution caused by direct discharge.

Compared with the traditional process, the removal method has the advantages of simple process, low price of used raw and auxiliary materials, low overall cost, high safety and stable production.

Detailed Description

The following describes embodiments of the present invention in detail with reference to the following embodiments. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.

It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the invention pertains.

Example 1

The embodiment is a method for removing nitric acid in a mixed acid solution, which comprises the following steps:

(a) heating the mixed acid solution to 30 ℃, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid;

(b) adding urea into the mixed acid solution until no bubbles are generated;

(c) and cooling the mixed acid solution to room temperature, and collecting sulfuric acid for recycling.

Example 2

The embodiment is a method for removing nitric acid in a mixed acid solution, which comprises the following steps:

(a) heating the mixed acid solution to 50 ℃, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid;

(b) adding urea into the mixed acid solution until no bubbles are generated;

(c) and cooling the mixed acid solution to room temperature, and collecting sulfuric acid for recycling.

Example 3

The embodiment is a method for removing nitric acid in a mixed acid solution, which comprises the following steps:

(a) heating the mixed acid solution to 42 ℃, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid;

(b) adding urea into the mixed acid solution until no bubbles are generated;

(c) and cooling the mixed acid solution to room temperature, and collecting sulfuric acid for recycling.

Example 4

The embodiment is a method for removing nitric acid in a mixed acid solution, which comprises the following steps:

(a) heating the mixed acid solution to 42 ℃, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid;

(b) adding urea into the mixed acid solution under the stirring condition of 20r/min until no bubbles are generated;

(c) and cooling the mixed acid solution to room temperature, and collecting sulfuric acid for recycling.

Example 5

The embodiment is a method for removing nitric acid in a mixed acid solution, which comprises the following steps:

(a) heating the mixed acid solution to 42 ℃, wherein the mixed acid solution is a mixed solution of sulfuric acid and nitric acid;

(b) adding urea into the mixed acid solution under the stirring condition of 10r/min until no bubbles are generated;

(c) and cooling the mixed acid solution to room temperature, and collecting sulfuric acid for recycling.

Comparative example 1

This comparative example is a method for removing nitric acid from a mixed acid solution, which is substantially the same as the method for removing nitric acid in example 3 except that in step (a), the mixed acid solution is heated to 60 ℃.

Examples of the experiments

Removing nitric acid in the same mixed acid solution according to the removing methods of the embodiments 1-5 and the comparative example 1 respectively; then, the concentrations of nitrate before and after removal were measured according to the standard measurement method for nitrate, and the removal rate was calculated, and the calculation results are shown in table 1:

TABLE 1 removal rates of different removal methods

Group of	Removal Rate (%)
		Example 1	94.8
Example 2	96.3
		Example 3	99.2
Example 4	99.4
		Example 5	99.1
Comparative example 1	89.5

As can be seen from Table 1:

according to the technical scheme, the nitric acid in the mixed acid solution can be efficiently removed, and the removal rate can reach 99.4% to the maximum; in addition, the removal method can realize the recycling of sulfuric acid, improve the resource utilization rate and reduce the environmental pollution caused by direct discharge.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.