Treatment method of wastewater containing nitric acid, sulfuric acid and nitrophenol energetic compounds

Abstract

The invention provides a treatment method of wastewater containing nitric acid, sulfuric acid and nitrophenol energetic compounds, and belongs to the field of solvent treatment. The method comprises the following steps: adsorbing wastewater containing nitric acid, sulfuric acid and nitrophenol energetic compounds by using resin to obtain adsorbed resin and filtrate; the resin is a polymer microporous spherical compound obtained by suspension polymerization of styrene and divinylbenzene; eluting the adsorbed resin by using a solvent medium to obtain an eluent; and drying the eluent. The resin obtained by suspension polymerization of styrene and divinylbenzene is used for adsorbing energetic compounds such as 2-nitrophloroglucinol, 2, 4-dinitro phloroglucinol and trinitro phloroglucinol in the wastewater, so that the safety of the subsequent process of distilling and recovering nitric acid and sulfuric acid can be effectively ensured; nitrophenol compounds can be collected and utilized as reactants of the next process, concentrated nitric acid and concentrated sulfuric acid in waste liquid can be recycled and utilized, and environmental pressure is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of solvent treatment, and in particular to a method for treating wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds, a preparation method thereof and an application thereof. Background Art

[0002] At present, there is no special treatment process for wastewater containing nitric acid, sulfuric acid and nitro-phenol compounds in the market. The wastewater containing nitric acid, sulfuric acid and nitro-phenol compounds is the waste liquid of the intermediate product in the synthesis of highly insensitive explosives. The amount used in the production process is large, and it is difficult to treat and discharge later. It is urgent to find a suitable method to treat the waste liquid of the intermediate product. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a method for treating wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds. The treatment method provided by the present invention has fast efficiency, high yield, low energy consumption, low separation cost, high purity of the recovered nitro-phenol compounds, and is simple and easy to operate, and is suitable for industrial production.

[0004] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0005] The present invention provides a method for treating wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds, comprising the following steps:

[0006] Adsorbing the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds with resin to obtain the adsorbed resin and filtrate; the resin is a macroporous spherical compound obtained by suspension polymerization of styrene and divinylbenzene;

[0007] Eluting the adsorbed resin with a solvent medium to obtain an eluate;

[0008] Drying the eluate.

[0009] Preferably, the mass ratio of styrene to divinylbenzene is 9:1.

[0010] Preferably, the particle size of the resin is 325-1350 μm, the water content is 20-30 wt%, the wet apparent density is 0.65-0.75 g / mL, the wet true density is 1.00-1.11 g / mL, and the specific surface area ≥ 1050 m 2 / g.

[0011] Preferably, the adsorption comprises the following steps: applying pressure to the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds to make the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds pass through a filter, and the filter contains the resin.

[0012] Preferably, the pressure applied is 0.12 to 0.15 MPa.

[0013] Preferably, the flow rate of the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds flowing out of the filter is 0.9 to 1.2 BV / h.

[0014] Preferably, the dosage of the resin is 1 to 1.1 BV.

[0015] Preferably, the COD content of the filtrate is < 150 mg / L.

[0016] Preferably, the solvent medium is an alcohol solvent, water or an alkaline solution.

[0017] Preferably, the parameters of the elution include: the flow rate is 1.5 to 2.0 BV / h, the volume ratio of the solvent medium to the resin is 1:1, and the pressure is 0.13 to 0.15 MPa.

[0018] The present invention provides a method for treating wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds, comprising the following steps: adsorbing the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds with a resin to obtain an adsorbed resin and a filtrate; the resin is a macroporous spherical compound obtained by suspension polymerization of styrene and divinylbenzene; eluting the adsorbed resin with a solvent medium to obtain an eluate; drying the eluate.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention provides a method with high efficiency, high yield, low energy consumption, low separation cost and high purity of the recovered nitro-phenol compounds, which is applicable to the separation, recovery and reuse of nitro-phenol compound waste liquid, is simple and easy to implement, and is suitable for industrial production; the present invention uses the resin obtained by suspension polymerization of styrene and divinylbenzene to adsorb energetic compounds such as 2-nitroresorcinol, 2,4-dinitroresorcinol and picric acid in the wastewater, which can effectively solve the safety problems in the subsequent distillation and recovery of nitric acid and sulfuric acid, can collect and utilize the nitro-phenol compounds as reactants for the next process, can recover and reuse the nitric acid and sulfuric acid in the waste liquid, and can be recycled to reduce the environmental pressure. Specific embodiments

[0021] The present invention provides a method for treating wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds, comprising the following steps:

[0022] Adsorbing the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds with a resin to obtain an adsorbed resin and a filtrate; the resin is a macroporous spherical compound obtained by suspension polymerization of styrene and divinylbenzene;

[0023] The adsorbed resin is eluted with a solvent medium to obtain an eluate.

[0024] The eluate is dried.

[0025] In the present invention, a resin is used to adsorb wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds, to obtain an adsorbed resin and a filtrate; the resin is a macroporous spherical compound obtained by suspension polymerization of styrene and divinylbenzene.

[0026] In the present invention, the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds (raw water) is preferably the waste liquid generated during the synthesis of energetic compounds. The content of acid in the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds is preferably 390,000 - 430,000 mg / L, the content of nitrate is preferably 14,500 - 16,000 mg / L, the content of sulfate is preferably 400,000 - 430,000 mg / L, the content of nitro-phenol compounds is preferably 1,700 - 2,000 ppm, the COD content is preferably 350 - 500 mg / L, the ammonia nitrogen content is preferably 3,800 - 4,500 mg / mL, the chromaticity is preferably 15 - 20 degrees (the solution is light yellowish green after being diluted 100 times), and the turbidity is preferably 9 - 10 (NTU).

[0027] In the present invention, the mass ratio of styrene to divinylbenzene is preferably 9:1.

[0028] In the present invention, the particle size of the resin is preferably 325 - 1350 μm, the water content is preferably 20 - 30 wt%, the wet apparent density is preferably 0.65 - 0.75 g / mL, the wet true density is preferably 1.00 - 1.11 g / mL, and the specific surface area is preferably ≥1050 m 2 / g.

[0029] In the present invention, the initiator for the suspension polymerization is preferably benzoyl peroxide (BPO), the dispersant is preferably cellulose. The suspension polymerization process preferably includes a first-stage kettle reaction and a second-stage kettle reaction. The temperature of the first-stage kettle reaction is preferably 80 - 83 °C, and the heat preservation time is preferably 2.5 - 3 h. The temperature of the second-stage kettle reaction is preferably 90 - 95 °C, and the heat preservation time is preferably 6 h.

[0030] In the present invention, the adsorption preferably includes the following steps: applying pressure to the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds, and passing the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds through a filter containing the resin.

[0031] In the present invention, the pressure applied is preferably 0.12 - 0.15 MPa, more preferably 0.13 - 0.14 MPa.

[0032] In the present invention, the flow rate of the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds flowing out of the filter is preferably 0.9 - 1.2 BV / h, more preferably 1 - 1.1 BV / h.

[0033] In the present invention, the dosage of the resin is preferably 1 - 1.1 BV.

[0034] In the present invention, the COD content of the filtrate is preferably < 150 mg / L.

[0035] In the present invention, the filtrate is preferably directly discharged after distilling and recovering sulfuric acid and nitric acid. The present invention has no special limitation on the specific manner of the distillation and recovery, and the methods well-known to those skilled in the art can be adopted.

[0036] In the present invention, the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds is preferably placed in a stock solution tank, and the filter is filled with resin. The filter is connected to an increasing pump, a flow meter, a stock solution tank and a filtrate tank. The increasing pump is turned on, and the set pressure value is 0.12 - 0.15 MPa, so that the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds is sucked from the stock solution tank, passes through the filter and flows to the filtrate tank until it is observed that the color of the resin in the filter has all turned dark brown and the filtrate index does not meet the requirement that the COD content < 150 mg / L, then the adsorption is stopped. The filtrate is directly discharged after distilling and recovering sulfuric acid and nitric acid.

[0037] In the present invention, the flow meter is preferably an intelligent electromagnetic digital display flow meter.

[0038] In the present invention, the single-column treatment capacity of the filter is preferably 4 - 6 BV.

[0039] In the present invention, the materials of the stock solution tank and the filtrate tank are both preferably high-density polyethylene; the material of the filter is Hastelloy or glass material, and the filter is preferably continuous adsorption and continuous desorption to fully save the waste liquid treatment time.

[0040] After obtaining the adsorbed resin, the present invention elutes the adsorbed resin with a solvent medium to obtain an eluate.

[0041] In the present invention, the solvent medium is preferably an alcohol solvent, water or an alkali solution.

[0042] In the present invention, the alcohol solvent is preferably methanol or ethanol, and the ethanol is preferably an ethanol solution not less than 95 vol%.

[0043] In the present invention, the alkali solution is preferably a sodium hydroxide solution, and the mass fraction of the sodium hydroxide solution is preferably 6% - 8%.

[0044] When the solvent medium is preferably an alcohol solvent, the temperature of the solvent medium is preferably 10 - 30°C; when the solvent medium is preferably water, the temperature of the solvent medium is preferably 40 - 50°C, and the higher the temperature of the water, the easier the desorption; when the solvent medium is preferably an alkali solution, the temperature of the solvent medium is preferably 10 - 30°C.

[0045] In the present invention, the parameters of the elution preferably include: the outflow rate is 1.5 - 2.0 BV / h, the volume ratio of the solvent medium to the resin is 1:1, and the pressure is 0.13 - 0.15 MPa.

[0046] In the present invention, the function of the elution is to separate and collect energetic compounds such as 2-nitroresorcinol, 2,4-dinitroresorcinol, and trinitroresorcinol adsorbed on the resin.

[0047] In the present invention, it is preferred to let the solvent medium flow out of the filter, and the eluted liquid is reused until it is observed that the color of the resin returns to its original color, and then the elution is stopped.

[0048] In the present invention, the number of times of reuse is preferably 6 - 8 times.

[0049] In the present invention, the outflow rate of the eluent is preferably 1.5 - 2.0 BV / h.

[0050] After obtaining the eluent, the present invention dries the eluent and preferably collects nitrophenol compounds.

[0051] In the present invention, the drying is preferably natural air drying.

[0052] In the present invention, it is preferred to place the eluted liquid in a drying pool for the drying.

[0053] In the present invention, the thickness of the drying pool is preferably 30 cm, and the volume is preferably 2 - 3 m 3 .

[0054] In the present invention, the drying pool is preferably lined with a high-density polyethylene waterproof and anti-seepage layer.

[0055] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the embodiments in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0056] The resins used in the embodiments of the present invention are all high-molecular microporous spherical compounds obtained by suspension polymerization of styrene and divinylbenzene. When preparing, the mass ratio of styrene to divinylbenzene is 9:1. The particle size of the resin is 325 - 1350 μm, the water content is 25 wt%, the wet apparent density is 0.70 g / mL, the wet true density is 1.10 g / mL, and the specific surface area is 1100 m 2 / g. The appearance is light yellow spherical particles; the initiator for suspension polymerization is benzoyl peroxide (BPO), and the dispersant is cellulose. The process of suspension polymerization includes a first-stage kettle reaction and a second-stage kettle reaction. The temperature of the first-stage kettle reaction is 80°C, and the heat preservation time is 3 h. The temperature of the second-stage kettle reaction is 90°C, and the heat preservation time is preferably 6 h.

[0057] Example 1

[0058] (1) Take 3000 mL of resin and place it in a filter composed of serially connected chromatography columns, compact and clamp it. A filter is composed of 6 serially connected 500 mL (6 BV value) chromatography columns. Take 2.0 L of wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds and place it in the stock solution barrel. Turn on the booster pump with a pressure of 0.12 MPa. The wastewater passes through each chromatography column in turn and flows out from the liquid outlet.

[0059] (2) After 1.2 L of the filtered liquid flows out, analyze and detect the filtrate in real time every 500 mL. After the treatment volume reaches 1.5 L, it is found that the filtrate index does not meet the COD content < 150 mg / L, and the color of the resin changes significantly, then stop filtering.

[0060] (3) Collect the filtrate for later use, and perform subsequent distillation to recover nitric acid and sulfuric acid for treatment;

[0061] (4) Take 6 L of 95 vol% ethanol solution and place it in the analytical solution barrel. Turn on the booster pump and flow it into and out of the filter at a flow rate of 1.5 BV / h times the speed, and flow it into the analytical solution barrel until the color of the chromatography column becomes significantly lighter. After repeating 6 times, collect it for later use.

[0062] (5) Concentrate and collect the eluent after repeating 6 times, place it in the drying pool, air-dry it naturally, and collect 30 g of nitro-phenol compounds.

[0063] (6) Place the filtrate in batches in a 5 L distillation flask to obtain dilute nitric acid with a mass fraction of 18% and sulfuric acid with a mass fraction of 65%.

[0064] Example 2

[0065] (1) Place 3000 mL of resin in a filter composed of a series of chromatography columns, compact and clamp it. A filter is composed of 6 series-connected 500 mL (6 BV value) chromatography columns. Place 2.0 L of wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds in the stock solution tank. Turn on the booster pump with a pressure of 0.15 MPa. The wastewater passes through each chromatography column in sequence and flows out from the outlet.

[0066] (2) After 1.2 L of the filtered liquid has flowed out, analyze and detect the filtrate in real time every 500 mL. After the treatment volume reaches 1.8 L, it is found that the filtrate index does not meet the requirement of COD content < 150 mg / L, and the color of the resin changes significantly. Stop filtration.

[0067] (3) Collect the filtrate for standby, and perform subsequent distillation to recover nitric acid and sulfuric acid for treatment;

[0068] (4) Place 6 L of 95 vol% ethanol solution in the eluent tank. Turn on the booster pump and flow it into and out of the filter at a flow rate of 1.5 BV / h, and flow it into the eluent tank until the color of the chromatography column becomes significantly lighter. After repeating 7 times, collect it for use.

[0069] (5) Collect the eluent after repeating 7 times and place it in the drying pool. After natural air drying, collect 25 g of nitro-phenol compounds.

[0070] (6) Place the filtrate in batches in a 5 L distillation flask to obtain dilute nitric acid with a mass fraction of 25% and sulfuric acid with a mass fraction of 60%.

[0071] Example 3

[0072] (1) Place 3000 mL of resin in a filter composed of a series of chromatography columns, compact and clamp it. A filter is composed of 6 series-connected 500 mL (6 BV value) chromatography columns. Place 2.0 L of wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds in the stock solution tank. Turn on the booster pump with a pressure of 0.12 MPa. The wastewater passes through each chromatography column in sequence and flows out from the outlet.

[0073] (2) After 1.2 L of the filtered liquid has flowed out, analyze and detect the filtrate in real time every 500 mL. After the treatment volume reaches 1.8 L, it is found that the filtrate index does not meet the requirement of COD content < 150 mg / L, and the color of the resin changes significantly. Stop filtration.

[0074] (3) Collect the filtrate for standby, and perform subsequent distillation to recover nitric acid and sulfuric acid for treatment;

[0075] (4) Place 6 L of 95 vol% ethanol solution in the analytical solution bucket, turn on the booster pump, and flow into and out of the filter at a flow rate of 2 BV / h, and flow back into the analytical solution bucket until the color of the chromatography column becomes significantly lighter. After repeating the use 8 times, collect it for later use.

[0076] (5) Collect the eluent after repeating the use 8 times, place it in the drying pool, let it air dry naturally, and collect 35 g of nitrophenol compounds.

[0077] (6) Place the filtrate in batches in a 5 L distillation flask to obtain dilute nitric acid with a mass fraction of 16% and sulfuric acid with a mass fraction of 50%.

[0078] Table 1 shows the detection data of the water quality during the treatment processes of Examples 1 to 3. It can be seen from Table 1 that the present invention provides a process for the adsorption treatment of wastewater containing nitric acid, sulfuric acid and nitrophenol energetic compounds, which can recycle nitrophenol compounds, and at the same time obtain nitric acid and sulfuric acid with different concentrations for use in other products, greatly reducing the generation amount of waste solvents, thereby reducing production costs and environmental protection pressure.

[0079] Table 1 Detection Results of Water Quality during the Treatment Processes of Examples 1 to 3

[0080]

[0081]

[0082] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for treating wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds, characterized in that, It includes the following steps: Adsorb the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds with resin to obtain the adsorbed resin and filtrate; the resin is a high-molecular microporous spherical compound obtained by suspension polymerization of styrene and divinylbenzene; Elute the adsorbed resin with a solvent medium to obtain an eluate; Dry the eluate.

2. The processing method according to claim 1, wherein, The mass ratio of styrene to divinylbenzene is 9:

1.

3. The processing method according to claim 1 or 2, characterized in that, The particle size of the resin is 325 to 1350 μm, the water content is 20 to 30 wt%, the wet bulk density is 0.65 to 0.75 g / mL, the wet true density is 1.00 to 1.11 g / mL, and the specific surface area is ≥ 1050 m 2 / g.

4. The processing method according to claim 1, characterized in that The adsorption includes the following steps: Apply pressure to the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds to make the wastewater pass through a filter containing the resin.

5. The processing method according to claim 4, characterized in that, The pressure applied is 0.12 - 0.15 MPa.

6. The processing method according to claim 4, wherein The flow rate of the wastewater containing nitric acid, sulfuric acid and nitro-phenol energetic compounds flowing out of the filter is 0.9 - 1.2 BV / h.

7. The processing method according to claim 1 or 4, characterized in that, The dosage of the resin is 1 - 1.1 BV.

8. The processing method according to claim 1, characterized in that The COD content of the filtrate is < 150 mg / L.

9. The processing method according to claim 1, characterized in that, The solvent medium is an alcohol solvent, water or an alkaline solution.

10. The processing method according to claim 1, characterized in that The parameters of the elution include: the flow rate is 1.5 - 2.0 BV / h, the volume ratio of the solvent medium to the resin is 1:1, and the pressure is 0.13 - 0.15 MPa.

Images