Method for preparing eutectic molecular sieve by using yellow phosphorus slag and application thereof

Abstract

The present application relates to a kind of methods for preparing eutectic molecular sieve with yellow phosphorus slag, specifically, after dry yellow phosphorus slag is ground and sieved, yellow phosphorus slag powder is obtained;Yellow phosphorus slag powder and NaOH are mixed uniformly, placed in a muffle furnace and calcined, removed and placed in water for rapid cooling, solid-liquid separation, NaAlO2 is added in liquid, stirred and mixed uniformly, then transferred to a reaction kettle for hydrothermal crystallization reaction, solid-liquid separation, and the eutectic molecular sieve is obtained by washing and drying the solid;The eutectic molecular sieve is used for adsorbing heavy metals in wastewater, and the material has good adsorption performance for heavy metal pollutants in wastewater, which can realize the purpose of waste treatment.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solid waste secondary utilization, and particularly relates to a method for preparing eutectic molecular sieves from yellow phosphorus slag and application thereof. BACKGROUND

[0002] Yellow phosphorus is an important basic industrial raw material and is widely used in chemical industry, agriculture, food, medical treatment and other fields. However, various solid wastes, mainly including yellow phosphorus slag, mud phosphorus, electric dust and the like, are generated in the production process of yellow phosphorus. About 8-12 tons of yellow phosphorus slag are generated per ton of yellow phosphorus. Most enterprises usually adopt the treatment method of stacking when treating the solid waste containing phosphorus. This not only occupies a large amount of land, but also pollutes underground water and soil under the action of rainwater, and the elements in the yellow phosphorus slag may also cause radioactive pollution during storage, affecting plant growth and human health. Therefore, developing a suitable method to realize the resource recycling of yellow phosphorus slag and developing functional materials from the yellow phosphorus slag to treat heavy metal pollutants in wastewater can not only realize the environment-friendly, but also avoid resource waste and achieve good economic benefits.

[0003] At present, the comprehensive utilization of yellow phosphorus slag includes recovery of valuable components (waste heat, silicon, calcium, rare earth metals), environmental remediation (wastewater treatment, soil remediation, carbon capture and utilization). The acid leaching method for extracting rare earth metals from yellow phosphorus slag has the advantages of high leaching rate and simultaneous leaching of multiple metals. However, due to the low content of rare earth elements in the yellow phosphorus slag, the cost of simply extracting rare earth elements is relatively high, and the complex process may cause the transfer of pollution, resulting in high actual treatment cost. Overall, various processes for recovering valuable components from yellow phosphorus slag have certain recovery capacity and good development prospects, but they are still in the academic research stage and have not been industrialized.

[0004] Based on the above problems, the comprehensive utilization and clean utilization of yellow phosphorus slag are necessary. SUMMARY

[0005] The application provides a method for preparing eutectic molecular sieves from yellow phosphorus slag, and the method is applied to adsorb heavy metal pollutants in wastewater.

[0006] In order to solve the above technical problems, the application adopts the following technical scheme:

[0007] 1. Dry the yellow phosphorus slag at 60-80 DEG C for 36-48 h, mechanically ball mill for 2-4 h, and sieve to obtain yellow phosphorus slag powder;

[0008] 2. Mix the yellow phosphorus slag powder and NaOH, grind uniformly, and then pour the sample into a nickel crucible, wherein the mass ratio of NaOH to yellow phosphorus slag powder is 3-7.5:1;

[0009] 3. Put the nickel crucible in the muffle furnace at 400-700 DEG C calcination 3-5h, take out and place in water rapid cooling 5-30min, after water immersion, solid-liquid separation, the mass volume ratio g:mL of yellow phosphorus slag powder and water is 1:90-110;

[0010] 4. Add NaAlO2 in the liquid, the volume mass ratio mL:g of the liquid and NaAlO2 is 220-240:1, after stirring uniformly at room temperature, transfer to the reaction kettle for hydrothermal crystallization at 100 DEG C for 8-24h, solid-liquid separation, and the solid is washed and dried to obtain the eutectic molecular sieve;

[0011] 5. The eutectic molecular sieve prepared by the above method is applied to adsorb heavy metals in wastewater, and the experimental results show that the purpose of removing Cu 2+ in wastewater can be achieved.

[0012] Compared with the prior art, the present application has the following advantages:

[0013] The present application uses industrial solid waste yellow phosphorus slag as raw material, and a eutectic molecular sieve material with FAU and LTA eutectic types is prepared by a simple alkali fusion-water immersion-hydrothermal crystallization method. The present application has the advantages of wide raw material sources, simple operation, no need to add seeds or templates in the synthesis process, high utilization rate of yellow phosphorus slag, and cost saving. The material has good adsorption performance on heavy metal pollutants in wastewater, and can achieve the purpose of waste treatment. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is the XRD pattern of yellow phosphorus slag;

[0015] Figure 2 It is the XRD pattern of the molecular sieve material prepared in Example 1 of the present application.

[0016] Figure 3 It is the SEM image of the zeolite molecular sieve prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0017] In order to better understand the specific content of the present application, the present application is described in detail through the following specific examples, but the protection scope of the present application is not limited to the following content. Example 1

[0018] (1) Take the yellow phosphorus slag and place it in an electric oven for constant temperature drying at 60 DEG C for 45h, mechanically ball mill for 4h, and then pass through a 180 mesh sieve to prepare yellow phosphorus slag powder. The XRD pattern of the yellow phosphorus slag is shown in Figure 1 ;

[0019] (2) Mix 2g of yellow phosphorus slag powder with 15g of NaOH in a mortar, and quickly stir and mix in the mortar, pour into a nickel crucible after grinding for 5min;

[0020] (3) After calcining the nickel crucible in the muffle furnace at 600℃ for 5h, the product was quickly placed in 200mL water for rapid cooling, and the solid-liquid was separated after the water immersion for 20min;

[0021] (4) NaAlO2 0.3g was added in 72mL solution, and after stirring at room temperature for 3h, it was transferred to the reaction kettle for hydrothermal crystallization at 100℃ for 8h to obtain the eutectic molecular sieve; the prepared molecular sieve was analyzed, and the XRD pattern thereof is shown in Figure 2 , and according to the PDF standard card in the pattern, it can be seen that the synthesized zeolite molecular sieve simultaneously exists in FAU and LTA type structures, indicating that the method synthesizes a FAU and LTA eutectic zeolite molecular sieve; in order to more intuitively describe the morphology and structure of the synthesized eutectic zeolite molecular sieve, SEM analysis was performed, and the results are shown in Figure 3 , which exists in the octahedral structure of FAU type zeolite, and also exists in irregular morphology and FAU and LTA coexisting morphology (red marked part in Figure 3 ).

[0022] (5) The eutectic molecular sieve was applied in Cu 2+ adsorption, 0.04g of the molecular sieve material was placed in 50mL, pH5, 150mg / L Cu 2+ solution, and adsorbed to saturation in a shaker at room temperature at 120r / min, and the adsorption capacity of the molecular sieve was 240.6mg / g. Example 2

[0023] (1) The yellow phosphorus slag was placed in an electric oven at 70℃ for constant temperature drying for 40h, mechanically ball milled for 2h, and then sieved through a 180 mesh sieve to prepare the yellow phosphorus slag powder;

[0024] (2) 2g of the yellow phosphorus slag powder was mixed with 12g of NaOH in a mortar, and quickly stirred and mixed, and then poured into a nickel crucible after grinding for 5min;

[0025] (3) After calcining the nickel crucible in the muffle furnace at 600℃ for 5h, the product was quickly placed in 200mL water for rapid cooling, and the solid-liquid was separated after the water immersion for 20min;

[0026] (4) NaAlO2 0.3g was added in 72mL solution, and after stirring at room temperature for 3h, it was transferred to the reaction kettle for hydrothermal crystallization at 100℃ for 12h to obtain the eutectic molecular sieve;

[0027] (5) The eutectic molecular sieve was applied in Cu 2+ adsorption, 0.04g of the molecular sieve material was placed in 50mL, pH5, 150mg / L Cu 2+In the solution, the adsorption capacity of the molecular sieve is 232.5 mg / g at room temperature in a 120 r / min oscillator. Example 3

[0028] (1) The yellow phosphorus slag was placed in an electric oven at 80°C for constant temperature drying for 36 h, mechanically ball-milled for 2 h, and then sieved through a 180-mesh sieve to prepare yellow phosphorus slag powder;

[0029] (2) 2 g of the yellow phosphorus slag powder was mixed with 10 g of NaOH in a mortar, and the mixture was quickly stirred and mixed for 5 min, and then poured into a nickel crucible;

[0030] (3) The nickel crucible was placed in a muffle furnace at 600°C for calcination for 5 h, and then the product was quickly placed in 200 mL of water for rapid cooling, and the solid-liquid separation was performed after the water immersion for 15 min;

[0031] (4) In 72 mL of the solution, 0.3 g of NaAlO2 was added, and the stirring was performed at room temperature for 3 h, and then the stirring solution was transferred into a reaction kettle for hydrothermal crystallization at 100°C for 12 h to obtain the eutectic molecular sieve;

[0032] (5) The eutectic molecular sieve was applied in Cu 2+ adsorption, 0.04 g of the molecular sieve material was placed in 50 mL of Cu 2+ solution with pH 5 and a Cu2+ concentration of 150 mg / L, and the adsorption was performed to saturation at room temperature in a 120 r / min oscillator, and the adsorption capacity of the molecular sieve was 228.8 mg / g. Example 4

[0033] (1) The yellow phosphorus slag was placed in an electric oven at 80°C for constant temperature drying for 40 h, mechanically ball-milled for 3 h, and then sieved through a 200-mesh sieve to prepare yellow phosphorus slag powder;

[0034] (2) 2 g of the yellow phosphorus slag powder was mixed with 10 g of NaOH in a mortar, and the mixture was quickly stirred and mixed for 5 min, and then poured into a nickel crucible;

[0035] (3) The nickel crucible was placed in a muffle furnace at 600°C for calcination for 5 h, and then the product was quickly placed in 200 mL of water for rapid cooling, and the solid-liquid separation was performed after the water immersion for 15 min;

[0036] (4) In 72 mL of the solution, 0.3 g of NaAlO2 was added, and the stirring was performed at room temperature for 3 h, and then the stirring solution was transferred into a reaction kettle for hydrothermal crystallization at 100°C for 12 h to obtain the eutectic molecular sieve;

[0037] (5) The eutectic molecular sieve was applied in Cu 2+ adsorption, 0.04 g of the molecular sieve material was placed in 50 mL of Cu 2+In the solution, the adsorption capacity of the molecular sieve is 217.5 mg / g at room temperature in a shaker at 120 r / min until saturation.

[0038] As can be seen from the above examples, the application uses solid waste yellow phosphorus slag as raw material, and a molecular sieve is prepared through a simple alkali fusion-water immersion-hydrothermal crystallization method. 2+ Good adsorption performance can be achieved.

[0039] The above merely describes preferred embodiments of the application, but is not intended to limit the scope of the application; if the application is modified or replaced equivalently without departing from the spirit and scope of the application, it should be covered in the protection scope of the claims of the application.

Claims

1. A eutectic molecular sieve prepared using yellow phosphorus slag for the removal of Cu from wastewater 2+ The application of this technology is characterized by: The preparation method of the eutectic molecular sieve is to ball-mill dried yellow phosphorus slag and sieve it to obtain yellow phosphorus slag powder; mix the yellow phosphorus slag powder and NaOH evenly, place it in a muffle furnace for calcination, take it out and place it in water for rapid cooling, separate the solid and liquid, add NaAlO2 to the liquid, stir and mix it evenly, transfer it to a reaction vessel for hydrothermal crystallization reaction, separate the solid and liquid, wash the solid, dry it, and obtain the desired product.

2. The application according to claim 1, characterized in that: The mass ratio of NaOH to yellow phosphorus slag powder is 3~7.5:

1.

3. The application according to claim 1, characterized in that: The roasting temperature is 400~700℃, the roasting time is 3~5h, and the water is rapidly cooled for 5~30min.

4. The application according to claim 1, characterized in that: The mass-to-volume ratio of yellow phosphorus slag powder to water (g:mL) is 1:90~110, and the volume-to-mass ratio of liquid to NaAlO2 after solid-liquid separation (mL:g) is 220~240:1.

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