Waste sulfuric acid recovery process based on isopropyl bromide recovery

Abstract

The invention belongs to the technical field of waste acid recovery and utilization, and provides a waste sulfuric acid recovery process based on isopropyl bromide recovery, the recovery process comprises the following specific steps: step 1, mixing sulfuric acid waste liquid, activated carbon and hydrogen peroxide, heating and stirring to obtain pretreated sulfuric acid waste liquid; step 2, adding an organic solvent into the pretreated sulfuric acid waste liquid for extraction; and step 3, carrying out resin adsorption on the extracted sulfuric acid waste liquid, and then carrying out reduced pressure distillation and concentration to obtain concentrated sulfuric acid. According to the sulfuric acid waste liquid recovery process provided by the invention, the sulfuric acid waste liquid can be well recovered, the environmental pollution is further reduced, and the resource utilization rate is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of waste acid recovery and utilization, and particularly relates to a waste sulfuric acid recovery process based on isopropyl bromide recovery. Background Art

[0002] Isopropyl bromide, also known as 2-bromopropane or isobromopropane, is an organic compound mainly used in the synthesis of drugs, dyes and other organic compounds.

[0003] Isopropyl bromide can be prepared by a variety of methods. The most common preparation method is to use isopropyl alcohol and concentrated hydrobromic acid to undergo a nucleophilic substitution reaction under the catalysis of concentrated sulfuric acid. Therefore, a large amount of waste acid will be generated during the production process. The waste acid will contain a small amount of organic, inorganic and other impurities, which are difficult to be directly used or the quality of the products produced by using it is poor. In addition, if it is directly discharged into the environment without treatment, it will cause serious pollution to the soil, water and organisms, affecting the health and stability of the ecosystem. At present, it is mainly treated as hazardous waste, which is difficult to treat and expensive.

[0004] Therefore, it is of great significance to develop a method for efficiently purifying and recycling waste sulfuric acid. Summary of the invention

[0005] In order to overcome the problem of difficulty in treating waste sulfuric acid, the present invention provides a waste sulfuric acid recovery process based on isopropyl bromide recovery.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A waste sulfuric acid recovery process based on isopropyl bromide recovery comprises the following steps:

[0008] Step 1, mixing sulfuric acid waste liquid, activated carbon and hydrogen peroxide, heating and stirring to obtain pretreated sulfuric acid waste liquid;

[0009] Step 2, adding an organic solvent to the pretreated sulfuric acid waste liquid for extraction;

[0010] Step 3: The extracted sulfuric acid waste liquid is subjected to resin adsorption, and then concentrated by vacuum distillation to obtain concentrated sulfuric acid.

[0011] As a further embodiment of the present invention, the specific surface area of ​​the activated carbon in step 1 is 1000-1200m 2 / g.

[0012] As a further embodiment of the present invention, in step 1, the usage ratio of the sulfuric acid waste liquid, the activated carbon and the hydrogen peroxide is 30 mL: 0.05-0.06 g: 1-1.25 mL.

[0013] As a further solution of the present invention, the temperature is raised to 30-70° C. in step 1. Certain temperature conditions will promote the catalytic oxidation reaction. When the reaction temperature is 30-70° C., hydrogen peroxide has an excellent catalytic oxidation effect on waste sulfuric acid, and the utilization rate of hydrogen peroxide is greatly improved.

[0014] As a further embodiment of the present invention, the volume ratio of the organic solvent to the pretreated sulfuric acid waste liquid in step 2 is 3:2.

[0015] As a further embodiment of the present invention, the organic solvent in step 2 is one of chloroform and carbon tetrachloride.

[0016] As a further embodiment of the present invention, the vacuum distillation in step 3 includes primary vacuum distillation concentration and secondary vacuum distillation concentration.

[0017] As a further embodiment of the present invention, in step 3, the temperature during the first-stage vacuum distillation and concentration is 150-160°C; and the temperature during the second-stage vacuum distillation and concentration is 320-340°C.

[0018] As a further embodiment of the present invention, the resin in step 3 is a macroporous adsorption resin.

[0019] As a further embodiment of the present invention, the macroporous adsorption resin is at least one of macroporous adsorption resin DH-1, macroporous adsorption resin DH-2, and macroporous adsorption resin D001.

[0020] Beneficial effects of the present invention:

[0021] In the present invention, activated carbon and hydrogen peroxide are used to carry out catalytic oxidation reaction on waste sulfuric acid. On the one hand, activated carbon is used as a catalyst for hydrogen peroxide oxidation to remove organic impurities in waste sulfuric acid, so that hydrogen peroxide is easily decomposed on the surface to produce hydroxyl radicals with strong oxidizing properties, thereby promoting the catalytic oxidation of waste sulfuric acid; on the other hand, activated carbon is used as an adsorbent to adsorb and remove organic impurities, thereby enhancing the removal effect of organic matter. Subsequently, the pretreated sulfuric acid waste liquid is extracted, adsorbed by resin, and distilled and concentrated to obtain a sulfuric acid solution with high purity, thereby realizing the recycling of sulfuric acid.

[0022] The waste sulfuric acid recovery process provided in the present invention has a simple process, effectively reduces environmental pressure, avoids waste of resources, solves the problem of high treatment cost and difficulty in treating waste sulfuric acid, and is conducive to further realizing the resource utilization of waste sulfuric acid. DETAILED DESCRIPTION

[0023] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] The indicators of sulfuric acid waste liquid adopted in the present invention are as follows:

[0025]

[0026] Example 1

[0027] The present embodiment provides a waste sulfuric acid recovery process based on isopropyl bromide recovery, comprising the following steps:

[0028] Step 1: 30L of sulfuric acid waste liquid, 0.05kg of activated carbon (specific surface area of ​​1000m 2 / g) and 1L of hydrogen peroxide, and then heated to 30°C and stirred to obtain a pretreated sulfuric acid waste liquid;

[0029] Step 2, adding 20L of carbon tetrachloride to the pretreated sulfuric acid waste liquid for extraction;

[0030] Step 3, subjecting the extracted sulfuric acid waste liquid to macroporous resin adsorption DH-1, and then sequentially subjecting the first-stage vacuum distillation concentration and the second-stage vacuum distillation concentration to a temperature of 150° C. and a temperature of 320° C. to obtain concentrated sulfuric acid.

[0031] Example 2

[0032] The present embodiment provides a waste sulfuric acid recovery process based on isopropyl bromide recovery, comprising the following steps:

[0033] Step 1: 30L of sulfuric acid waste liquid, 0.055kg of activated carbon (specific surface area of ​​1000m 2 / g) and 1% hydrogen peroxide, and then heated to 45° C. and stirred to obtain a pretreated sulfuric acid waste liquid;

[0034] Step 2, adding 20L of carbon tetrachloride to the pretreated sulfuric acid waste liquid for extraction;

[0035] Step 3, subjecting the extracted sulfuric acid waste liquid to macroporous resin adsorption DH-1, and then sequentially subjecting the first-stage vacuum distillation concentration and the second-stage vacuum distillation concentration to a temperature of 150° C. and a temperature of 320° C. to obtain concentrated sulfuric acid.

[0036] Example 3

[0037] The present embodiment provides a waste sulfuric acid recovery process based on isopropyl bromide recovery, comprising the following steps:

[0038] Step 1: 30L of sulfuric acid waste liquid, 0.06kg of activated carbon (specific surface area of ​​1100m 2 / g) and 1.15 L of hydrogen peroxide, and then heated to 50° C. and stirred to obtain a pretreated sulfuric acid waste liquid;

[0039] Step 2, adding 20L and carbon tetrachloride to the pretreated sulfuric acid waste liquid for extraction;

[0040] Step 3, subjecting the extracted sulfuric acid waste liquid to macroporous resin adsorption DH-1, and then sequentially subjecting the first-stage vacuum distillation concentration and the second-stage vacuum distillation concentration to a temperature of 155° C. and a temperature of 330° C. to obtain concentrated sulfuric acid.

[0041] Example 4

[0042] The present embodiment provides a waste sulfuric acid recovery process based on isopropyl bromide recovery, comprising the following steps:

[0043] Step 1: 30L of sulfuric acid waste liquid, 0.06kg of activated carbon (specific surface area of ​​1000m 2 / g) and 1.25 L of hydrogen peroxide, and then heated to 65° C. and stirred to obtain a pretreated sulfuric acid waste liquid;

[0044] Step 2, adding 20L of chloroform to the pretreated sulfuric acid waste liquid for extraction;

[0045] Step 3, subjecting the extracted sulfuric acid waste liquid to macroporous resin adsorption DH-1, and then sequentially subjecting the first-stage vacuum distillation concentration and the second-stage vacuum distillation concentration to a temperature of 160° C. and a temperature of 340° C. to obtain concentrated sulfuric acid.

[0046] Comparative Example 1

[0047] This comparative example provides a waste sulfuric acid recovery process based on isopropyl bromide recovery, comprising the following steps:

[0048] Step 1, after mixing 30L of sulfuric acid waste liquid and 1L of hydrogen peroxide, heating to 30°C and stirring to obtain pretreated sulfuric acid waste liquid;

[0049] Step 2, adding 20L of carbon tetrachloride to the pretreated sulfuric acid waste liquid for extraction;

[0050] Step 3, subjecting the extracted sulfuric acid waste liquid to macroporous resin adsorption DH-1, and then sequentially subjecting the first-stage vacuum distillation concentration and the second-stage vacuum distillation concentration to a temperature of 150° C. and a temperature of 320° C. to obtain concentrated sulfuric acid.

[0051] Comparative Example 2

[0052] This comparative example provides a waste sulfuric acid recovery process based on isopropyl bromide recovery, comprising the following steps:

[0053] Step 1: 30L of sulfuric acid waste liquid, 0.035kg of activated carbon (specific surface area of ​​1000m 2 / g) and 1L of hydrogen peroxide, and then heated to 30°C and stirred to obtain a pretreated sulfuric acid waste liquid;

[0054] Step 2, adding 20L of carbon tetrachloride to the pretreated sulfuric acid waste liquid for extraction;

[0055] Step 3, subjecting the extracted sulfuric acid waste liquid to macroporous resin adsorption DH-1, and then sequentially subjecting the first-stage vacuum distillation concentration and the second-stage vacuum distillation concentration to a temperature of 150° C. and a temperature of 320° C. to obtain concentrated sulfuric acid.

[0056] Comparative Example 3

[0057] This comparative example provides a waste sulfuric acid recovery process based on isopropyl bromide recovery, comprising the following steps:

[0058] Step 1: 30L of sulfuric acid waste liquid, 0.05kg of activated carbon (specific surface area of ​​1000m 2 / g) and 1L of hydrogen peroxide, and then heated to 30°C and stirred to obtain a pretreated sulfuric acid waste liquid;

[0059] Step 2, adding 15L of carbon tetrachloride to the pretreated sulfuric acid waste liquid for extraction;

[0060] Step 3, subjecting the extracted sulfuric acid waste liquid to macroporous resin adsorption DH-1, and then sequentially subjecting the first-stage vacuum distillation concentration and the second-stage vacuum distillation concentration to a temperature of 150° C. and a temperature of 320° C. to obtain concentrated sulfuric acid.

[0061] Performance tests were performed on Examples 1 to 4 and Comparative Examples 1 to 3, and the test results are shown in Table 1:

[0062] Table 1

[0063]

[0064] It can be seen from Table 1 that, compared with Comparative Examples 1-3, the effect of treating sulfuric acid waste liquid in Examples 1-4 is more excellent. It can be seen that the sulfuric acid waste liquid recovery process provided by the present invention can well recover and treat sulfuric acid waste liquid, further reduce environmental pollution, and improve resource utilization.

[0065] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0066] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A waste sulfuric acid recovery process based on isopropyl bromide recovery, characterized in that, The following steps are involved: Step 1, mixing sulfuric acid waste liquid, activated carbon and hydrogen peroxide, heating and stirring to obtain pretreated sulfuric acid waste liquid; Step 2, adding an organic solvent to the pretreated sulfuric acid waste liquid for extraction; Step 3: The extracted sulfuric acid waste liquid is subjected to resin adsorption, and then concentrated by vacuum distillation to obtain concentrated sulfuric acid.

2. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 1, characterized in that, The specific surface area of ​​the activated carbon in step 1 is 1000-1200m 2 / g.

3. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 1, characterized in that, In step 1, the usage ratio of sulfuric acid waste liquid, activated carbon and hydrogen peroxide is 30mL: 0.05-0.06g: 1-1.25mL.

4. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 1, characterized in that, In step 1, the temperature is raised to 30-70°C.

5. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 1, characterized in that: In step 2, the volume ratio of the organic solvent to the pretreated sulfuric acid waste liquid is 3:

2.

6. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 1, characterized in that: The organic solvent in step 2 is one of chloroform and carbon tetrachloride.

7. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 1, characterized in that: The vacuum distillation in step 3 includes primary vacuum distillation concentration and secondary vacuum distillation concentration.

8. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 1, characterized in that: In step 3, the temperature during the first-stage vacuum distillation concentration is 150-160° C.; the temperature during the second-stage vacuum distillation concentration is 320-340° C.

9. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 1, characterized in that: The resin in step 3 is a macroporous adsorption resin.

10. A waste sulfuric acid recovery process based on isopropyl bromide recovery according to claim 9, characterized in that: The macroporous adsorption resin is at least one of macroporous adsorption resin DH-1, macroporous adsorption resin DH-2, and macroporous adsorption resin D001.

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