Adsorbent for azole organic wastewater treatment and preparation method and application thereof

Abstract

This invention provides an adsorbent for treating azole-containing organic wastewater, its preparation method, and its application. The adsorbent comprises a zeolite molecular sieve and metal components I and II supported on the zeolite molecular sieve, wherein metal component I is selected from at least one of Cu, Fe, and Zn, and metal component II is selected from at least one of Ca, Ce, and La. This adsorbent, used in the adsorption treatment of azole-containing organic wastewater, has the advantages of being inexpensive, recyclable, and having low biotoxicity in the effluent. Furthermore, this invention also provides a method for treating azole-containing organic wastewater.

Description

Technical Field

[0001] This invention relates to an adsorbent and its preparation method. This invention also relates to a method for treating azole-based organic wastewater. Background Technology

[0002] Wastewater from industries such as pesticides, pharmaceuticals, and explosives contains large amounts of organic azole pollutants, which are structurally stable and difficult to degrade. To leverage the advantages of biological treatment—low ​​toxicity, low investment, and low treatment costs—it is necessary to find effective pretreatment methods to treat organic azole pollutants in wastewater. Zeolite molecular sieves, with their well-developed pore structure and large specific surface area, are common adsorbents. Through physical and chemical modification, their adsorption performance for specific substances can be improved.

[0003] Invention CN113003834A discloses a method for treating wastewater from the production of pyrazole pesticides, which recovers pyrazole compounds by adsorption using macroporous resin. However, this method is only applicable to the recovery of single pyrazole components and is not suitable for wastewater containing complex components.

[0004] CN110354824A discloses an adsorbent for the adsorption treatment of wastewater containing wetting agents. The adsorbent contains a variety of active groups and can remove oil, COD, heavy metals and SS from water. However, the adsorbent does not have a significant advantage in the adsorption of azole organic matter and is difficult to regenerate. Summary of the Invention

[0005] To address the problems of high energy consumption and poor biodegradability of effluent in existing technologies for treating azole-containing organic wastewater, this invention first provides a novel adsorbent and its preparation method. This adsorbent, used in the adsorption treatment of azole-containing organic wastewater, has the advantages of being inexpensive, recyclable, and producing effluent with low biotoxicity. Furthermore, this invention also provides a method for treating azole-containing organic wastewater.

[0006] The present invention provides an adsorbent for treating azole organic wastewater, comprising a zeolite molecular sieve and metal component I and metal component II supported on the zeolite molecular sieve, wherein metal component I is selected from at least one of Cu, Fe, and Zn, and metal component II is selected from at least one of Ca, Ce, and La.

[0007] According to some embodiments of the present invention, the mass content of metal component I, calculated as metal element, is greater than 0 and less than 20 g / kg, preferably 0.5-10 g / kg, and more preferably 1-3 g / kg.

[0008] According to some embodiments of the present invention, the mass content of metal component II, calculated as metal element, is greater than 0 and less than 20 g / kg, preferably 0.5-10 g / kg, and more preferably 1-3 g / kg.

[0009] According to some embodiments of the present invention, the mass ratio of metal component I to metal component II is 0.1-10, preferably 0.5-2.

[0010] According to some embodiments of the present invention, the zeolite molecular sieve is ZSM-5 molecular sieve, SAPO-34 molecular sieve, NaY molecular sieve, USY molecular sieve, X-type molecular sieve, or Y-type molecular sieve. Preferably, the zeolite molecular sieve is ZSM-5 molecular sieve.

[0011] The method for preparing the adsorbent provided by the present invention includes the following steps: 1) soaking the zeolite molecular sieve in a hydrochloric acid or ammonium salt solution; 2) soaking the zeolite molecular sieve treated in step 1) in a salt solution of metal component II and calcining it to obtain a catalyst precursor; 3) soaking the catalyst precursor obtained in step 2) in a salt solution of metal component I and calcining it.

[0012] According to the present invention, in step 1), soaking with an ammonium salt solution is preferred, as it is more effective than hydrochloric acid solution. According to some embodiments of the present invention, in step 1), the ammonium salt content in the aqueous ammonium salt solution is 1-5 wt%. In some embodiments, the aqueous ammonium salt solution is an aqueous ammonium nitrate solution.

[0013] According to some embodiments of the present invention, in step 1), the soaking time is 8-12 hours.

[0014] According to some embodiments of the present invention, in step 1), the soaking temperature is 20-60°C.

[0015] According to some embodiments of the present invention, in step 2), the soaking time is 8-12 hours.

[0016] According to some embodiments of the present invention, in step 2), the soaking temperature is 40-80°C.

[0017] According to some embodiments of the present invention, in step 3), the calcination temperature is 200-300°C and the calcination time is 1-2 hours.

[0018] According to some embodiments of the present invention, in step 3), the soaking is ultrasonic-assisted soaking.

[0019] According to some embodiments of the present invention, in step 3), the soaking time is 2-4 hours.

[0020] According to some embodiments of the present invention, in step 3), the soaking temperature is 20-80°C.

[0021] According to some embodiments of the present invention, in step 3), the calcination temperature is 300-600°C and the calcination time is 2-4 hours.

[0022] According to some embodiments of the present invention, the salt solution of metal component I includes at least one of a halide (such as a chloride, bromide, etc.), a nitrate, and a sulfate of metal component I. In some embodiments, the salt solution of metal component I includes CuSO4.

[0023] According to some embodiments of the present invention, the salt solution of metal component II includes at least one of a halide (such as a chloride, bromide, etc.), nitrate, and sulfate of metal component I. In some embodiments, the salt solution of metal component I includes Ce(NO3)3.

[0024] The present invention provides a method for treating azole-containing organic wastewater, which includes adsorbing the azole-containing organic wastewater with the adsorbent described in the present invention.

[0025] According to some embodiments of the present invention, in the adsorption treatment, the pH value of the azole-containing organic wastewater can be controlled to be 6-8, the adsorption time can be 2-4 hours, the adsorption temperature can be 20-60℃, and the stirring speed can be 50-200 r / min.

[0026] According to some embodiments of the present invention, the treatment method further includes soaking the adsorbent after adsorption treatment in hydrogen peroxide for desorption. Preferably, the soaking temperature is 2-6 hours and the soaking time is 40-100°C.

[0027] According to some embodiments of the present invention, the concentration of hydrogen peroxide is 5-10 wt%.

[0028] Using the technical solution of this invention, under the conditions of reaction temperature 40℃, reaction time 2h, pH value 8, stirring speed 100r / min, and adsorbent usage of 10g per liter of wastewater, taking pyrazole simulated wastewater as an example, using the adsorbent of this invention (e.g., Cu / Ce bimetallic supported zeolite molecular sieve as adsorbent), the degradation rate of azole organic matter and TOC in the pyrazole simulated wastewater both reached 80%, and the wastewater B / C ratio increased from 0.01 to 0.4, significantly improving the biodegradability of the wastewater. After the adsorbent was desorbed by soaking in 8w% hydrogen peroxide at 60℃ for 4h, it was reused three times, and the degradation rate of azole organic matter and TOC did not decrease significantly, achieving good technical results. Attached Figure Description

[0029] Figure 1 The images show the Py-IR (pyridine infrared) spectra of the modified zeolite molecular sieve adsorbent A (1) prepared in Example 1 and the raw material zeolite molecular sieve (2) used in Example 1. Detailed Implementation

[0030] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0031] In this invention, the pyridine infrared spectrum was detected by a ThermoFisherNicolet 6700FT-IR spectrometer.

[0032] Example 1

[0033] Adsorbent preparation

[0034] 50g of ZSM-5 molecular sieve was soaked in a 1% ammonium nitrate aqueous solution at 40℃ for 8 hours, filtered, washed with water, and then soaked in 50ml of Ce(NO3)3·6H2O aqueous solution containing 0.05g Ce at 80℃ for 8 hours. It was then calcined at 240℃ for 2 hours, and then soaked in CuSO4·5H2O aqueous solution containing 0.05g Cu at 60℃. The solution was then ultrasonically assisted in soaking for 3 hours in an ultrasonic oscillator, calcined at 400℃ for 4 hours, and ground to obtain modified zeolite molecular sieve adsorbent A. Detailed information about the adsorbent is shown in Table 1.

[0035] Adsorbent applications:

[0036] Pyrazole-simulated wastewater (pyrazole concentration: 2128 mg / L) and modified zeolite molecular sieve adsorbent A were added to the reactor for adsorption treatment. The adsorbent dosage was 10 g / L of wastewater. The pH was adjusted to 8, the temperature was 40℃, the reactor stirring speed was 100 r / min, and the adsorption time was 2 h. The reaction results are shown in Table 2.

[0037] Adsorbent regeneration:

[0038] The adsorbent A after the above adsorption treatment was desorbed by soaking in hydrogen peroxide under the following conditions: temperature 60℃, time 4h, and H2O2 concentration 8w%. The desorbed adsorbent was reused three times.

[0039] Example 2

[0040] Adsorbent preparation

[0041] 50g of ZSM-5 molecular sieve was soaked in a 1% ammonium nitrate aqueous solution at 40℃ for 8 hours, filtered, washed with water, and then soaked in 50ml of a LaCl3 aqueous solution containing 0.05g of La at 80℃ for 8 hours. It was then calcined at 240℃ for 2 hours, and then soaked in a FeSO4·7H2O aqueous solution containing 0.05g of Fe at 60℃. The solution was then ultrasonically assisted in soaking for 3 hours in an ultrasonic oscillator, calcined at 400℃ for 4 hours, and ground to obtain modified zeolite molecular sieve adsorbent B. Detailed information about the adsorbent is shown in Table 1.

[0042] Adsorbent applications:

[0043] Pyrazole-simulated wastewater (pyrazole concentration: 2098 mg / L) and modified zeolite molecular sieve adsorbent B were added to the reactor for adsorption treatment. The adsorbent dosage was 10 g / L of wastewater. The pH was adjusted to 7.5, the temperature was 40℃, the reactor stirring speed was 80 r / min, and the adsorption time was 2 h. The reaction results are shown in Table 2.

[0044] Adsorbent regeneration:

[0045] The adsorbent after the above adsorption treatment was desorbed by soaking in hydrogen peroxide under the following conditions: temperature 60℃, time 4h, and H2O2 concentration 8w%. The desorbed adsorbent was reused.

[0046] Example 3

[0047] Adsorbent preparation

[0048] 50g of ZSM-5 molecular sieve was soaked in a 1w% ammonium nitrate aqueous solution at 40℃ for 8 hours, filtered, washed with water, and then soaked in 50ml of a CaCl2 aqueous solution containing 0.05g Ca at 80℃ for 8 hours. It was then calcined at 240℃ for 2 hours, and then soaked in a ZnSO4 aqueous solution containing 0.05g Zn at 60℃. The solution was then ultrasonically assisted in soaking for 3 hours in an ultrasonic oscillator, calcined at 400℃ for 4 hours, and ground to obtain modified zeolite molecular sieve adsorbent C. Detailed information about the adsorbent is shown in Table 1.

[0049] A mixture of simulated wastewater (containing organic compounds such as pyrazole, imidazole, thiazole, acetic acid, acrylic acid, and butanediol; TOC: 1002 mg / L; azole concentration: 2128 mg / L) and modified zeolite molecular sieve adsorbent C were added to the reactor for adsorption treatment. The adsorbent dosage was 10 g / L of wastewater. The pH was adjusted to 6, the temperature was 40℃, the reactor stirring speed was 150 r / min, and the adsorption time was 2 h. The reaction results are shown in Table 2.

[0050] Adsorbent regeneration:

[0051] The adsorbent after the above adsorption treatment was desorbed by soaking in hydrogen peroxide under the following conditions: temperature 60℃, time 4h, and H2O2 concentration 8w%. The desorbed adsorbent was reused.

[0052] Comparative Example 1

[0053] Preparation of adsorbent

[0054] The ZSM-5 molecular sieve was washed with water and ground into adsorbent a. Detailed information about the adsorbent is shown in Table 1.

[0055] Adsorbent applications:

[0056] Pyrazole-simulated wastewater (pyrazole concentration: 2128 mg / L) and adsorbent a were added to the reactor for adsorption treatment. The adsorbent dosage was 10 g / L of wastewater. The pH was adjusted to 8, the temperature was 40℃, the reactor stirring speed was 100 r / min, and the adsorption time was 2 h. The reaction results are shown in Table 2.

[0057] Examples 4-12 and Comparative Examples 2-4

[0058] The only difference from Example 1 is the metal components I and II in the preparation of the adsorbent, the specific composition of which is shown in Table 1.

[0059] The reaction results are shown in Table 2.

[0060] Example 13

[0061] Adsorbent preparation:

[0062] 50g of ZSM-5 molecular sieve was soaked in a 1% hydrochloric acid aqueous solution at 60℃ for 8 hours, filtered, washed with water, and then soaked in 50ml of Ce(NO3)3·6H2O aqueous solution containing 0.05gCe at 80℃ for 8 hours. It was then calcined at 240℃ for 2 hours, and then soaked in CuSO4·5H2O aqueous solution containing 0.05gCu at 40℃. The solution was then ultrasonically assisted in soaking for 3 hours in an ultrasonic oscillator, calcined at 400℃ for 4 hours, and ground to obtain a modified zeolite molecular sieve adsorbent. Detailed information about the adsorbent is shown in Table 1.

[0063] Adsorbent applications:

[0064] Pyrazole-simulated wastewater (pyrazole concentration: 2098 mg / L) and modified zeolite molecular sieve adsorbent B were added to the reactor for adsorption treatment. The adsorbent dosage was 10 g / L of wastewater. The pH was adjusted to 7.5, the temperature was 40℃, the reactor stirring speed was 80 r / min, and the adsorption time was 2 h. The reaction results are shown in Table 2.

[0065] Adsorbent regeneration:

[0066] The adsorbent after the above adsorption treatment was desorbed by soaking in hydrogen peroxide under the following conditions: temperature 60℃, time 4h, and H2O2 concentration 8w%. The desorbed adsorbent was reused.

[0067] Example 14

[0068] Adsorbent preparation:

[0069] 50g of ZSM-5 molecular sieve was soaked in a 1% hydrochloric acid aqueous solution at 40℃ for 8 hours, filtered, washed with water, and then soaked in 50ml of a mixed aqueous solution containing 0.05g Ce of Ce(NO3)3·6H2O and 0.05g Cu of CuSO4·5H2O. The solution was soaked at 80℃ for 8 hours, calcined at 240℃ for 4 hours, and then ground to obtain a modified zeolite molecular sieve adsorbent. Detailed information about the adsorbent is shown in Table 1.

[0070] Adsorbent applications:

[0071] Pyrazole-simulated wastewater (pyrazole concentration: 2098 mg / L) and modified zeolite molecular sieve adsorbent B were added to the reactor for adsorption treatment. The adsorbent dosage was 10 g / L of wastewater. The pH was adjusted to 7.5, the temperature was 40℃, the reactor stirring speed was 80 r / min, and the adsorption time was 2 h. The reaction results are shown in Table 2.

[0072] Adsorbent regeneration:

[0073] The adsorbent after the above adsorption treatment was desorbed by soaking in hydrogen peroxide under the following conditions: temperature 60℃, time 4h, and H2O2 concentration 8w%. The desorbed adsorbent was reused.

[0074] Example 15

[0075] Adsorbent preparation:

[0076] 50g of ZSM-5 molecular sieve was soaked in a 1% hydrochloric acid aqueous solution at 60℃ for 8 hours, filtered, washed with water, and then soaked in a CuSO4·5H2O aqueous solution containing 0.05g Cu at 40℃. The solution was then ultrasonically assisted for 3 hours in an ultrasonic oscillator, calcined at 400℃ for 4 hours, and then soaked in 50ml of a Ce(NO3)3·6H2O aqueous solution containing 0.05g Ce for 8 hours at 80℃. The solution was then calcined at 240℃ for 2 hours and ground to obtain a modified zeolite molecular sieve adsorbent. Detailed information about the adsorbent is shown in Table 1.

[0077] Adsorbent applications:

[0078] Pyrazole-simulated wastewater (pyrazole concentration: 2098 mg / L) and modified zeolite molecular sieve adsorbent B were added to the reactor for adsorption treatment. The adsorbent dosage was 10 g / L of wastewater. The pH was adjusted to 7.5, the temperature was 40℃, the reactor stirring speed was 80 r / min, and the adsorption time was 2 h. The reaction results are shown in Table 2.

[0079] Adsorbent regeneration:

[0080] The adsorbent after the above adsorption treatment was desorbed by soaking in hydrogen peroxide under the following conditions: temperature 60℃, time 4h, and H2O2 concentration 8w%. The desorbed adsorbent was reused.

[0081] Table 1. Adsorbent Details

[0082]

[0083]

[0084] Table 2. Reaction Results

[0085]

[0086]

[0087]

[0088]

[0089] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. The application of an adsorbent in the treatment of azole-based organic wastewater, said adsorbent comprising a zeolite molecular sieve and metal component I and metal component II supported on the zeolite molecular sieve, wherein, Metal component I is selected from at least one of Cu, Fe, and Zn, and metal component II is selected from at least one of Ca, Ce, and La. The zeolite molecular sieve is ZSM.

5. Molecular sieves, SAPO 34. At least one of the following: molecular sieve, NaY molecular sieve, USY molecular sieve, X-type molecular sieve, or Y-type molecular sieve; In the adsorbent, the mass content of metal component I, calculated as metal element, is 0.5-3 g / kg; In the adsorbent, the mass content of metal component II, calculated as metal element, is 0.5-3 g / kg; The mass ratio of metal component I to metal component II is 0.5-2:

1.

2. The application according to claim 1, wherein the method for preparing the adsorbent comprises the following steps: 1) Soak the zeolite molecular sieve in hydrochloric acid or ammonium salt solution; 2) The zeolite molecular sieve treated in step 1) is soaked in a salt solution of metal component II and then calcined to obtain a catalyst precursor; 3) The catalyst precursor obtained in step 2) is soaked in a salt solution of metal component I and then calcined.

3. The application according to claim 2, characterized in that, Step 1) The ammonium salt content in the ammonium salt aqueous solution is 1-5 wt%, and the soaking time is 8-12 hours; and / or Step 2) The soaking time is 8-12 hours; and / or the calcination temperature in Step 2) is 200-300℃, and the calcination time is 1-2 hours; and / or Step 3) The soaking is ultrasonic-assisted soaking, and the soaking time is 2-4 hours; and / or the calcination temperature in Step 3) is 300-600℃, and the calcination time is 2-4 hours.

4. A method for treating azole-containing organic wastewater, comprising adsorbing the azole-containing organic wastewater with an adsorbent. The adsorbent comprises a zeolite molecular sieve and metal components I and II supported on the zeolite molecular sieve, wherein, Metal component I is selected from at least one of Cu, Fe, and Zn, and metal component II is selected from at least one of Ca, Ce, and La. The zeolite molecular sieve is ZSM.

5. Molecular sieves, SAPO 34. At least one of the following: molecular sieve, NaY molecular sieve, USY molecular sieve, X-type molecular sieve, or Y-type molecular sieve; In the adsorbent, the mass content of metal component I, calculated as metal element, is 0.5-3 g / kg; In the adsorbent, the mass content of metal component II, calculated as metal element, is 0.5-3 g / kg; The mass ratio of metal component I to metal component II is 0.5-2:

1.

5. The processing method according to claim 4, characterized in that, In the adsorption treatment, the pH value of the azole-containing organic wastewater is controlled at 6-8, the adsorption time is 2-4 hours, the adsorption temperature is 20-60℃, and the stirring speed is 50-200 r / min.

6. The processing method according to claim 4, characterized in that, This also includes soaking the adsorbent after adsorption treatment in hydrogen peroxide to desorb it.

7. The processing method according to claim 6, characterized in that, Soaking temperature is 2-6 hours, soaking time is 40-100℃.

8. The processing method according to claim 6, characterized in that, The concentration of hydrogen peroxide is 5-10 wt%.

9. The treatment method according to any one of claims 4-8, wherein the preparation method of the adsorbent comprises the following steps: 1) Soak the zeolite molecular sieve in hydrochloric acid or ammonium salt solution; 2) The zeolite molecular sieve treated in step 1) is soaked in a salt solution of metal component II and then calcined to obtain a catalyst precursor; 3) The catalyst precursor obtained in step 2) is soaked in a salt solution of metal component I and then calcined.

10. The processing method according to claim 9, characterized in that, Step 1) The ammonium salt content in the ammonium salt aqueous solution is 1-5 wt%, and the soaking time is 8-12 hours; and / or Step 2) The soaking time is 8-12 hours; and / or the calcination temperature in Step 2) is 200-300℃, and the calcination time is 1-2 hours; and / or Step 3) The soaking is ultrasonic-assisted soaking, and the soaking time is 2-4 hours; and / or the calcination temperature in Step 3) is 300-600℃, and the calcination time is 2-4 hours.

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