Preparation method of self-cleaning stepped ring filler

Abstract

This invention relates to a method for preparing a self-purifying stepped ring packing, belonging to the field of water pollution purification materials. The method comprises the following steps: after acid washing and activation of ceramic stepped rings, a neodymium-niobium-zinc precursor is sprayed onto the surface of the ceramic stepped rings using a thermal spraying method. A series of drying and calcination processes are then performed to coat the surface of the ceramic stepped rings with a neodymium-niobium-zinc composite oxide active coating. The coating accounts for 3.6% to 3.9% of the total mass of the self-purifying stepped ring packing and exhibits high activity in decomposing organic pollutants. This packing can stably remove organic pollutants from wastewater over a long period, requiring minimal maintenance and regeneration during use, and has broad application prospects in practical wastewater treatment.

Description

Technical Field

[0001] This invention belongs to the field of water pollution purification materials, specifically relating to a method for preparing a self-purifying stepped ring packing. Background Technology

[0002] Industrial wastewater contains a wide variety of organic compounds, some of which pose serious threats to humans and the environment. Such industrial wastewater must undergo a rigorous pollution purification process before being discharged.

[0003] Common methods for treating organic wastewater typically require the use of various types of packing materials, depending on the wastewater treatment process and the type and concentration of pollutants in the water. The function of the packing materials is to adsorb and intercept pollutants in the wastewater; however, this results in a large amount of pollutants covering the surface of the packing materials, thus affecting their continued effectiveness. Microorganisms in biological treatment processes can decompose organic pollutants attached to the packing materials, but they lack sufficient purification capacity for highly toxic organic wastewater. Water treatment packing materials with self-purification capabilities have broad application prospects in practical wastewater treatment processes. Summary of the Invention

[0004] In view of the problems existing in the prior art, the present invention aims to provide a method for preparing a self-cleaning stepped ring packing, which can be used for the purification treatment of organic pollutants in water.

[0005] A method for preparing a self-cleaning stepped ring packing includes the following process steps:

[0006] Step 1: Activate the ceramic stepped ring

[0007] The ceramic stepped ring was immersed in 0.1 mol / L hydrochloric acid solution, heated to 75°C and held for 60 min to remove impurities from the ceramic stepped ring. The surface of the ceramic stepped ring was roughened by dissolving some of the alumina components on the surface of the ceramic stepped ring. It was then washed with pure water and dried at 110°C for 6 h to obtain the activated ceramic stepped ring.

[0008] Step 2: Preparation of Nd:niobium-zinc precursor

[0009] (1) Add 3.5–3.7 g of emulsifier OP-7, 5.2–5.8 g of neodymium nitrate hexahydrate (NdN3O9·6H2O), and 4.7–5.1 g of [unspecified ingredient] to 150 mL of pure water. Niobium acid (C 10 H5NbO 20 ), stir to form solution A;

[0010] (2) Add 6.5–7.3 mL of triethanolamine and 15–17 g of zinc stearate (C) to 200 mL of ethanol. 36 H70 O4Zn), stir to form solution B;

[0011] (3) Mix solution A and solution B and stir until homogeneous to form neodymium-niobium-zinc precursor;

[0012] Step 3: Apply composite oxide coating

[0013] (1) Heat the neodymium-niobium-zinc precursor to 60°C and spray it onto the surface of the activated ceramic step ring in step 1 at a flow rate of 10 mL / min using a constant flow pump until the surface of the activated ceramic step ring is completely and evenly coated.

[0014] (2) The activated ceramic stepped rings after spraying are dried at 120℃ for 6 hours, then calcined at 350~370℃ for 2 hours, and then calcined at 520~560℃ for 3 hours to obtain the self-cleaning stepped ring filler.

[0015] The ceramic stepped ring is made of alumina ceramic, with an outer diameter of 25–76 mm and a specific surface area of ​​75–210 m². 2 / m 3 The porosity is 73%–78%, and the bulk weight is 530–650 kg / m³. 3 .

[0016] The self-cleaning stepped ring packing has a neodymium-niobium-zinc composite oxide active coating coated on the surface of the ceramic stepped ring. The coating accounts for 3.6% to 3.9% of the total mass of the self-cleaning stepped ring packing. The mass percentages of neodymium oxide, niobium oxide, and zinc oxide in the coating are 39.0% to 39.3%, 22.3% to 22.8%, and 37.9% to 38.7%, respectively.

[0017] The specific surface area of ​​the self-cleaning stepped ring packing is 105-233 m². 2 / m 3 The porosity is 75%–77%.

[0018] Compared with the prior art, the advantages of the present invention are as follows:

[0019] This invention involves acid-washing and activating ceramic stepped rings, then using a thermal spraying method to apply a neodymium-niobium-zinc precursor to the surface of the ceramic stepped rings. Following a series of drying and calcination processes, a neodymium-niobium-zinc composite oxide active coating is applied to the acid-washed and activated ceramic stepped ring surface, ensuring a tight bond between the coating and the ceramic stepped ring surface. The relative proportions of neodymium oxide, niobium oxide, and zinc oxide in the neodymium-niobium-zinc composite oxide are precisely controlled to achieve high activity in decomposing organic pollutants. The self-cleaning stepped ring packing exhibits good porosity and flow performance, along with excellent high-temperature resistance and corrosion resistance. This packing can stably remove organic pollutants from wastewater over a long period without requiring frequent maintenance and regeneration, making it a promising candidate for practical wastewater treatment. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Reagents or instruments used, unless otherwise specified, are all commercially available products.

[0021] Example 1

[0022] A method for preparing a self-cleaning stepped ring packing includes the following process steps:

[0023] Step 1: Activate the ceramic stepped ring

[0024] (1) Immerse a ceramic stepped ring with an outer diameter of 76 mm in a 0.1 mol / L hydrochloric acid solution, heat the solution to 75 °C and keep it at that temperature for 60 min to remove impurities from the ceramic stepped ring, and make the surface of the ceramic stepped ring rough by dissolving some of the surface alumina components; wash the ceramic stepped ring treated above with pure water and dry it at 110 °C for 6 h to obtain an activated ceramic stepped ring.

[0025] Step 2: Preparation of Nd:niobium-zinc precursor

[0026] (1) Add 3.5g of emulsifier OP-7, 5.2g of nitrate hexahydrate (NdN3O9·6H2O), and 4.7g of [unclear text] to 150mL of pure water. Niobium acid (C 10 H5NbO 20 ), stir to form solution A;

[0027] (2) Add 6.5 mL of triethanolamine and 15 g of zinc stearate (C) to 200 mL of ethanol. 36 H 70 O4Zn), stir to form solution B;

[0028] (3) Mix solution A and solution B and stir until homogeneous to form neodymium-niobium-zinc precursor;

[0029] Step 3: Apply composite oxide coating

[0030] (1) Heat the neodymium-niobium-zinc precursor from step 2 to 60°C and spray it onto the surface of the activated ceramic step ring from step 1 at a flow rate of 10 mL / min using a constant flow pump until the surface of the activated ceramic step ring is completely and evenly coated.

[0031] (2) The activated ceramic stepped rings after spraying are dried at 120℃ for 6 hours, then calcined at 350℃ for 2 hours, and then calcined at 520℃ for 3 hours to obtain the self-cleaning stepped ring filler.

[0032] The neodymium-niobium-zinc composite oxide active coating on the surface of the ceramic stepped rings accounts for 3.6% of the total mass of the self-cleaning stepped ring packing; the specific surface area of ​​the self-cleaning stepped ring packing is 10⁵ m². 2 / m 3 The porosity is 75%.

[0033] Example 2

[0034] A method for preparing a self-cleaning stepped ring packing includes the following process steps:

[0035] Step 1: Activate the ceramic stepped ring

[0036] (1) Immerse a ceramic stepped ring with an outer diameter of 50 mm in a 0.1 mol / L hydrochloric acid solution, heat the solution to 75 °C and keep it at that temperature for 60 min to remove impurities from the ceramic stepped ring, and make the surface of the ceramic stepped ring rough by dissolving some of the surface alumina components; wash the ceramic stepped ring treated above with pure water and dry it at 110 °C for 6 h to obtain an activated ceramic stepped ring.

[0037] Step 2: Preparation of Nd:niobium-zinc precursor

[0038] (1) Add 3.5g of emulsifier OP-7, 5.3g of neodymium nitrate hexahydrate (NdN3O9·6H2O), and 4.8g of [unclear text] to 150mL of pure water. Niobium acid (C 10 H5NbO 20 ), stir to form solution A;

[0039] (2) Add 6.7 mL of triethanolamine and 15.5 g of zinc stearate (C) to 200 mL of ethanol. 36 H 70 O4Zn), stir to form solution B;

[0040] (3) Mix solution A and solution B and stir until homogeneous to form neodymium-niobium-zinc precursor.

[0041] Step 3: Apply composite oxide coating

[0042] (1) Heat the neodymium-niobium-zinc precursor from step 2 to 60°C and spray it onto the surface of the activated ceramic step ring from step 1 at a flow rate of 10 mL / min using a constant flow pump until the surface of the activated ceramic step ring is completely and evenly coated.

[0043] (2) The sprayed activated ceramic stepped rings were dried at 120℃ for 6 hours, then calcined at 355℃ for 2 hours, and then calcined at 530℃ for 3 hours to obtain the self-cleaning stepped ring packing. The Nd:niobium-zinc composite oxide active coating on the surface of the ceramic stepped rings accounted for 3.7% of the total mass of the self-cleaning stepped ring packing; the specific surface area of ​​the self-cleaning stepped ring packing was 138 m². 2 / m 3 The porosity is 75%.

[0044] Example 3

[0045] A method for preparing a self-cleaning stepped ring packing includes the following process steps:

[0046] Step 1: Activate the ceramic stepped ring

[0047] (1) Immerse a ceramic stepped ring with an outer diameter of 50 mm in a 0.1 mol / L hydrochloric acid solution, heat the solution to 75 °C and keep it at that temperature for 60 min to remove impurities from the ceramic stepped ring, and make the surface of the ceramic stepped ring rough by dissolving some of the surface alumina components; wash the ceramic stepped ring treated above with pure water and dry it at 110 °C for 6 h to obtain an activated ceramic stepped ring.

[0048] Step 2: Preparation of Nd:niobium-zinc precursor

[0049] (1) Add 3.6g of emulsifier OP-7, 5.5g of neodymium nitrate hexahydrate (NdN3O9·6H2O), and 4.9g of [unclear text] to 150mL of pure water. Niobium acid (C 10 H5NbO 20 ), stir to form solution A;

[0050] (2) Add 6.9 mL of triethanolamine and 16 g of zinc stearate (C) to 200 mL of ethanol. 36 H 70 O4Zn), stir to form solution B;

[0051] (3) Mix solution A and solution B and stir until homogeneous to form neodymium-niobium-zinc precursor.

[0052] Step 3: Apply composite oxide coating

[0053] (1) Heat the neodymium-niobium-zinc precursor from step 2 to 60°C and spray it onto the surface of the activated ceramic step ring from step 1 at a flow rate of 10 mL / min using a constant flow pump until the surface of the activated ceramic step ring is completely and evenly coated.

[0054] (2) The sprayed activated ceramic stepped rings were dried at 120℃ for 6 hours, then calcined at 360℃ for 2 hours, and finally calcined at 540℃ for 3 hours to obtain the self-cleaning stepped ring packing. The Nd:niobium-zinc composite oxide active coating on the surface of the ceramic stepped rings accounted for 3.7% of the total mass of the self-cleaning stepped ring packing; the specific surface area of ​​the self-cleaning stepped ring packing was 186 m². 2 / m 3 The porosity is 76%.

[0055] Example 4

[0056] A method for preparing a self-cleaning stepped ring packing includes the following process steps:

[0057] Step 1: Activate the ceramic stepped ring

[0058] (1) Immerse a ceramic stepped ring with an outer diameter of 38 mm in a 0.1 mol / L hydrochloric acid solution, heat the solution to 75 °C and keep it at that temperature for 60 min to remove impurities from the ceramic stepped ring, and make the surface of the ceramic stepped ring rough by dissolving some of the surface alumina components; wash the ceramic stepped ring treated above with pure water and dry it at 110 °C for 6 h to obtain an activated ceramic stepped ring.

[0059] Step 2: Preparation of Nd:niobium-zinc precursor

[0060] (1) Add 3.6g of emulsifier OP-7, 5.6g of neodymium nitrate hexahydrate (NdN3O9·6H2O), and 4.9g of other ingredients to 150mL of pure water. Niobium acid (C 10 H5NbO 20 ), stir to form solution A;

[0061] (2) Add 7.1 mL of triethanolamine and 16 g of zinc stearate (C) to 200 mL of ethanol. 36 H 70 O4Zn), stir to form solution B;

[0062] (3) Mix solution A and solution B and stir until homogeneous to form neodymium-niobium-zinc precursor.

[0063] Step 3: Apply composite oxide coating

[0064] (1) Heat the neodymium-niobium-zinc precursor from step 2 to 60°C and spray it onto the surface of the activated ceramic step ring from step 1 at a flow rate of 10 mL / min using a constant flow pump until the surface of the activated ceramic step ring is completely and evenly coated.

[0065] (2) The sprayed activated ceramic stepped rings were dried at 120℃ for 6 hours, then calcined at 365℃ for 2 hours, and then calcined at 550℃ for 3 hours to obtain the self-cleaning stepped ring packing. The Nd:niobium-zinc composite oxide active coating on the surface of the ceramic stepped rings accounted for 3.8% of the total mass of the self-cleaning stepped ring packing; the specific surface area of ​​the self-cleaning stepped ring packing was 201 m². 2 / m 3 The porosity is 76%.

[0066] Example 5

[0067] A method for preparing a self-cleaning stepped ring packing includes the following process steps:

[0068] Step 1: Activate the ceramic stepped ring

[0069] (1) Immerse a ceramic stepped ring with an outer diameter of 25 mm in a 0.1 mol / L hydrochloric acid solution, heat the solution to 75 °C and keep it at that temperature for 60 min to remove impurities from the ceramic stepped ring, and make the surface of the ceramic stepped ring rough by dissolving some of the surface alumina components; wash the ceramic stepped ring treated above with pure water and dry it at 110 °C for 6 h to obtain an activated ceramic stepped ring.

[0070] Step 2: Preparation of Nd:niobium-zinc precursor

[0071] (1) Add 3.7g of emulsifier OP-7, 5.8g of neodymium nitrate hexahydrate (NdN3O9·6H2O), and 5.1g of... to 150mL of pure water. Niobium acid (C 10 H5NbO 20 ), stir to form solution A;

[0072] (2) Add 7.3 mL of triethanolamine and 17 g of zinc stearate (C) to 200 mL of ethanol. 36 H 70 O4Zn), stir to form solution B;

[0073] (3) Mix solution A and solution B and stir until homogeneous to form neodymium-niobium-zinc precursor.

[0074] Step 3: Apply composite oxide coating

[0075] (1) Heat the neodymium-niobium-zinc precursor from step 2 to 60°C and spray it onto the surface of the activated ceramic step ring from step 1 at a flow rate of 10 mL / min using a constant flow pump until the surface of the activated ceramic step ring is completely and evenly coated.

[0076] (2) The sprayed activated ceramic stepped rings were dried at 120℃ for 6 hours, then calcined at 370℃ for 2 hours, and then calcined at 560℃ for 3 hours to obtain the self-cleaning stepped ring packing. The Nd:niobium-zinc composite oxide active coating on the surface of the ceramic stepped rings accounted for 3.9% of the total mass of the self-cleaning stepped ring packing; the specific surface area of ​​the self-cleaning stepped ring packing was 233 m². 2 / m 3 The porosity is 77%.

Claims

1. A method for preparing a self-cleaning stepped ring packing, characterized in that, The process includes the following steps: Step 1: Activate the ceramic stepped ring The ceramic stepped ring was immersed in 0.1 mol / L hydrochloric acid solution, heated to 75°C and held for 60 min to remove impurities from the ceramic stepped ring. The surface of the ceramic stepped ring was roughened by dissolving some of the alumina components on the surface of the ceramic stepped ring. It was then washed with pure water and dried at 110°C for 6 h to obtain the activated ceramic stepped ring. Step 2: Preparation of Nd:niobium-zinc precursor (1) Add 3.5–3.7 g of emulsifier OP-7, 5.2–5.8 g of neodymium nitrate hexahydrate (NdN3O9·6H2O), and 4.7–5.1 g of niobium oxalate (C) to 150 mL of pure water. 10 H5NbO 20 Stirring forms solution A; (2) Add 6.5–7.3 mL of triethanolamine and 15–17 g of zinc stearate (C) to 200 mL of ethanol. 36 H 70 O4Zn), stir to form solution B; (3) Mix solution A and solution B and stir until homogeneous to form neodymium-niobium-zinc precursor; Step 3: Apply a composite oxide coating (1) Heat the neodymium-niobium-zinc precursor to 60°C and spray it onto the surface of the activated ceramic step ring in step 1 at a flow rate of 10 mL / min using a constant flow pump until the surface of the activated ceramic step ring is completely and evenly coated. (2) The activated ceramic stepped rings after spraying are dried at 120℃ for 6 hours, then calcined at 350~370℃ for 2 hours, and then calcined at 520~560℃ for 3 hours to obtain the self-cleaning stepped ring filler.

2. The method for preparing a self-cleaning stepped ring packing according to claim 1, characterized in that, The ceramic stepped ring is made of alumina ceramic, with an outer diameter of 25–76 mm and a specific surface area of ​​75–210 m². 2 / m 3 The porosity is 73%–78%, and the bulk weight is 530–650 kg / m³. 3 .

3. The method for preparing a self-cleaning stepped ring packing according to claim 1, characterized in that, The self-cleaning stepped ring packing has a neodymium-niobium-zinc composite oxide active coating coated on the surface of the ceramic stepped ring. The coating accounts for 3.6% to 3.9% of the total mass percentage of the self-cleaning stepped ring packing. The mass percentages of neodymium oxide, niobium oxide, and zinc oxide in the coating are 39.0% to 39.3%, 22.3% to 22.8%, and 37.9% to 38.7%, respectively.

4. The method for preparing a self-cleaning stepped ring packing according to claim 1, characterized in that, The specific surface area of ​​the self-cleaning stepped ring packing is 105-233 m². 2 / m 3 The porosity is 75%–77%.