Diatom pure aldehyde shaving board and preparation method thereof

Abstract

The present application relates to a kind of diatom net aldehyde shaving board and its preparation method, belong to timber processing technical field.A kind of preparation method of diatom net aldehyde shaving board, comprising the following steps: S1, preparation active lignin-active diatomite compound;S2, take active lignin-active diatomite compound, epoxy resin adhesive and fine wood shaving are stirred evenly, obtain surface layer slurry;S3, take active lignin-active diatomite compound, epoxy resin adhesive and coarse wood shaving are stirred evenly, obtain core layer slurry;S4, take surface layer slurry, core layer slurry, surface layer slurry are sequentially added curing agent, sequentially layered paving, hot-pressing forming, diatom net aldehyde shaving board is obtained.The present application solves the technical problem that the hardness of the existing shaving board containing diatomite component is low, and the effect of adsorbing external formaldehyde is poor.

Description

Technical Field

[0001] This invention relates to a particleboard product and its preparation method, specifically to a diatomaceous earth aldehyde-removing particleboard and its preparation method. Background Technology

[0002] The raw materials for making particleboard include wood or wood fiber materials and adhesives. Urea-formaldehyde resin or phenolic resin is commonly used as the adhesive. Urea-formaldehyde resin has a low curing temperature and good bonding effect on particleboard made from various plant materials such as wheat straw and rice husks. Its hot-pressing temperature is 195–210℃, and it is widely used in production. However, both its use in particleboard manufacturing and subsequent use release free formaldehyde, polluting the environment. While phenolic resin has advantages such as high bonding strength, water resistance, heat resistance, wear resistance, and good chemical stability, its use in particleboard manufacturing and subsequent use also releases free formaldehyde, polluting the environment.

[0003] Diatomaceous earth is a porous material with low cost, large specific surface area, and stable chemical properties. There are precedents for incorporating diatomaceous earth into particleboard to produce low-formaldehyde particleboard. However, existing diatomaceous earth-containing particleboard has low hardness and poor adsorption of external formaldehyde. Summary of the Invention

[0004] The main objective of this invention is to provide a diatomaceous earth-based formaldehyde-removing particleboard and its preparation method, which solves the technical problems of existing particleboards containing diatomaceous earth having low hardness and poor adsorption effect on external formaldehyde.

[0005] To achieve the above objectives, the present invention provides a method for preparing diatomaceous earth aldehyde-removing particleboard, comprising the following steps:

[0006] S1. Preparation of active lignin-active diatomaceous earth complex;

[0007] S2. Take the active lignin-active diatomaceous earth composite, epoxy resin adhesive and fine wood shavings and mix them evenly to obtain the surface slurry.

[0008] S3. Take the active lignin-active diatomaceous earth composite, epoxy resin adhesive and coarse wood shavings and mix them evenly to obtain the core layer slurry.

[0009] S4. Take the surface slurry, core slurry and surface slurry in sequence, add the curing agent, lay them in layers in sequence, and hot press to form, and you will get diatomaceous earth aldehyde-free particleboard.

[0010] As a preferred embodiment, in step S1, the preparation method of the active lignin-active diatomaceous earth composite includes the following steps:

[0011] A. Take 7-8 parts by weight of diatomaceous earth and 2-3 parts by weight of lignin and add them to a mixed solution of phosphoric acid and sulfuric acid. After soaking, filter to obtain the filter residue.

[0012] B. Take the filter residue, heat it at 300-400℃ for 6-8 hours, cool it, and then heat it at 600-700℃ for 2-3 hours to obtain intermediate product I;

[0013] C. Take hydrochloric acid to wash intermediate product I, then wash with water until the residual liquid is free of chloride ions, dry at 400-500℃, cool and pass through a 40-60 mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0014] As a preferred embodiment, in step A, the method for preparing the phosphoric acid-sulfuric acid mixed solution is as follows:

[0015] Take 20 volume parts of 30wt% sulfuric acid solution and 10 volume parts of 10wt% phosphoric acid solution and mix them to obtain the phosphoric acid-sulfuric acid mixed solution.

[0016] The amount of the phosphoric acid-sulfuric acid mixed solution used is 25-30 parts by volume;

[0017] The ratio of parts by weight to parts by volume is g:mL.

[0018] As a preferred embodiment, in step C, the concentration of the hydrochloric acid is 0.1 mol / L, 100 volumes of the hydrochloric acid are used for each wash, and the number of hydrochloric acid washes is 3-4.

[0019] As a preferred embodiment, in step S2, the amount of active lignin-active diatomaceous earth composite is 2-4 parts by weight, the amount of epoxy resin adhesive is 8-12 parts by weight, the amount of fine wood shavings is 84-90 parts by weight, and the total weight of active lignin-active diatomaceous earth composite, epoxy resin adhesive and fine wood shavings is 100g.

[0020] As a preferred embodiment, in step S3, the amount of active lignin-active diatomaceous earth composite is 2-4 parts by weight, the amount of epoxy resin adhesive is 8-12 parts by weight, the amount of coarse wood shavings is 84-90 parts by weight, and the total weight of active lignin-active diatomaceous earth composite, epoxy resin adhesive and coarse wood shavings is 100g.

[0021] As a preferred embodiment, in steps S2 and S3, the epoxy resin adhesive is epoxy resin E44.

[0022] As a preferred embodiment, in step S4, the curing agent is an isocyanate curing agent, and the amount of the curing agent is 1-2 parts by weight.

[0023] As a preferred embodiment, in step S4, the temperature of the hot pressing is 200-220℃ and the pressure is 3-5MPa.

[0024] The present invention also provides a diatomaceous earth formaldehyde-removing particleboard.

[0025] The beneficial effects achieved by this invention are as follows:

[0026] This invention uses a unique method to treat lignin and diatomaceous earth to obtain an active lignin-active diatomaceous earth composite. Using the active lignin-active diatomaceous earth composite as part of the raw material to prepare particleboard can improve the formaldehyde removal efficiency of particleboard, purify formaldehyde in the air, and thus avoid the harm of formaldehyde to human health.

[0027] The active lignin-active diatomaceous earth composite prepared by this invention, when used in conjunction with epoxy resin adhesive, can give particleboard stronger static bending strength, elastic modulus and internal bonding strength. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0029] This invention discloses a diatomaceous earth aldehyde-removing particleboard and its preparation method, comprising the following steps:

[0030] S1. Preparation of active lignin-active diatomite complex

[0031] Step A: Take 7-8g of diatomaceous earth and 2-3g of lignin and add them to 25-30mL of phosphoric acid-sulfuric acid mixed solution (the phosphoric acid-sulfuric acid mixed solution is prepared by mixing 20mL of 30wt% sulfuric acid solution and 10mL of 10wt% phosphoric acid solution), soak for a while (about 1-2 hours), then filter to obtain filter residue;

[0032] Step B: Take the filter residue, heat it at 300-400℃ for 6-8 hours, cool it, and then heat it at 600-700℃ for 2-3 hours to obtain intermediate product I;

[0033] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3-4 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400-500℃, cool and pass through a 40-60 mesh sieve to obtain the lignin-active diatomaceous earth composite.

[0034] In the preparation of the active lignin-active diatomaceous earth composite of the present invention, after treatment with a phosphoric acid-sulfuric acid mixed solution, followed by secondary high-temperature heating, and then washing and drying, the adsorption capacity of active lignin-active diatomaceous earth can be improved, and the mechanical properties of particleboard can also be enhanced.

[0035] S2. Take 2-4g of active lignin-active diatomaceous earth composite, 8-12g of epoxy resin E44 and 84-90g of fine wood shavings and stir them evenly to obtain a surface slurry. The total weight of active lignin-active diatomaceous earth composite, epoxy resin adhesive and fine wood shavings is 100g.

[0036] S3. Take 2-4g of active lignin-active diatomaceous earth composite, 8-12g of epoxy resin e44 and 84-90g of coarse wood shavings and stir them evenly to obtain core layer slurry. The total weight of active lignin-active diatomaceous earth composite, epoxy resin adhesive and coarse wood shavings is 100g.

[0037] S4. Take 1-2g of isocyanate curing agent and add it to each of the surface slurry, core slurry and surface slurry. Lay them in layers in sequence and hot press them into shape. The hot pressing temperature is 200-220℃, the pressure is 3-5MPa and the hot pressing time is 3-4min. After hot pressing, let it stand at room temperature for 24h to obtain diatomaceous earth formaldehyde-free particleboard.

[0038] Example 1

[0039] This embodiment is a diatomaceous earth formaldehyde-removing particleboard and its preparation method, including the following steps:

[0040] S1. Preparation of active lignin-active diatomite complex

[0041] Step A: Add 7g of diatomaceous earth and 2g of lignin to 25mL of phosphoric acid-sulfuric acid mixed solution, soak for 1 hour, and then filter to obtain the filter residue;

[0042] Step B: Take the filter residue, heat it at 300°C for 6 hours, cool it, and then heat it at 600°C for 2 hours to obtain intermediate product I;

[0043] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 40-mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0044] S2. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of fine wood shavings and stir them evenly to obtain the surface slurry.

[0045] S3. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0046] S4. Take 1g of isocyanate curing agent and add it to each of the surface slurry, core slurry and surface slurry. Lay them in layers in sequence, and hot press them to form. The hot pressing temperature is 200℃, the pressure is 3MPa and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain diatomaceous earth formaldehyde-free particleboard.

[0047] Example 2

[0048] This embodiment is a diatomaceous earth formaldehyde-removing particleboard and its preparation method, including the following steps:

[0049] S1. Preparation of active lignin-active diatomite complex

[0050] Step A: Add 8g of diatomaceous earth and 3g of lignin to 30mL of phosphoric acid-sulfuric acid mixed solution, soak for about 2 hours, and then filter to obtain the filter residue;

[0051] Step B: Take the filter residue, heat it at 400°C for 8 hours, cool it, and then heat it at 700°C for 3 hours to obtain intermediate product I;

[0052] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 4 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 500℃, cool and pass through a 60-mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0053] S2. Take 4g of active lignin-active diatomaceous earth composite, 12g of epoxy resin e44 and 84g of fine wood shavings and stir them evenly to obtain the surface slurry.

[0054] S3. Take 4g of active lignin-active diatomaceous earth composite, 12g of epoxy resin e44 and 84g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0055] S4. Take 2g of isocyanate curing agent from each of the surface slurry, core slurry, and surface slurry, lay them in layers in sequence, and hot press them into shape. The hot pressing temperature is 220℃, the pressure is 5MPa, and the hot pressing time is 4min. After hot pressing, let it stand at room temperature for 24h to obtain diatomaceous earth formaldehyde-free particleboard.

[0056] Example 3

[0057] This embodiment is a diatomaceous earth formaldehyde-removing particleboard and its preparation method, including the following steps:

[0058] S1. Preparation of active lignin-active diatomite complex

[0059] Step A: Add 7g of diatomaceous earth and 3g of lignin to 25mL of phosphoric acid-sulfuric acid mixed solution, soak for 2 hours, and then filter to obtain filter residue;

[0060] Step B: Take the filter residue, heat it at 300°C for 8 hours, cool it, and then heat it at 600°C for 3 hours to obtain intermediate product I;

[0061] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 500℃, cool and pass through a 40-mesh sieve to obtain the active lignin-active diatomaceous earth complex.

[0062] S2. Take 4g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44, and 88g of fine wood shavings and mix them evenly.

[0063] S3. Take 2g of active lignin-active diatomaceous earth composite, 12g of epoxy resin e44 and 86g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0064] S4. Take 1g of isocyanate curing agent from each of the surface slurry, core slurry, and surface slurry, lay them in layers in sequence, and hot press them into shape. The hot pressing temperature is 220℃, the pressure is 3MPa, and the hot pressing time is 4min. After hot pressing, let it stand at room temperature for 24h to obtain diatomaceous earth aldehyde-free particleboard.

[0065] Example 4

[0066] This embodiment is a diatomaceous earth formaldehyde-removing particleboard and its preparation method, including the following steps:

[0067] S1. Preparation of active lignin-active diatomite complex

[0068] Step A: Add 8g of diatomaceous earth and 2g of lignin to 30mL of phosphoric acid-sulfuric acid mixed solution, soak for 1 hour, and then filter to obtain the filter residue.

[0069] Step B: Take the filter residue, heat it at 400°C for 6 hours, cool it, and then heat it at 700°C for 2 hours to obtain intermediate product I;

[0070] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 4 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 60-mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0071] S2. Take 2g of active lignin-active diatomaceous earth composite, 12g of epoxy resin e44 and 86g of fine wood shavings and stir them evenly to obtain the surface slurry.

[0072] S3. Take 4g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 88g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0073] S4. Take 2g of isocyanate curing agent from each of the surface slurry, core slurry, and surface slurry, lay them in layers in sequence, and hot press them into shape. The hot pressing temperature is 200℃, the pressure is 5MPa, and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain diatomaceous earth formaldehyde-free particleboard.

[0074] Comparative Example 1

[0075] This comparative example is a method for preparing activated carbon formaldehyde-removing particleboard, including the following steps:

[0076] S1. Preparation of activated diatomaceous earth

[0077] Step A: Add 7g of diatomaceous earth to 25mL of phosphoric acid-sulfuric acid mixed solution, soak for 1 hour, and then filter to obtain the filter residue;

[0078] Step B: Take the filter residue, heat it at 300°C for 6 hours, cool it, and then heat it at 600°C for 2 hours to obtain intermediate product I;

[0079] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 40-mesh sieve to obtain the active diatomaceous earth. Take 2 g of lignin and mix it with the obtained active diatomaceous earth to obtain a lignin-active diatomaceous earth complex.

[0080] S2. Take 2g of lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of fine wood shavings and stir them evenly to obtain the surface slurry.

[0081] S3. Take 2g of lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0082] S4. Take 1g of isocyanate curing agent and add it to each of the surface slurry, core slurry and surface slurry. Lay them in layers in sequence, and hot press them to form. The hot pressing temperature is 200℃, the pressure is 3MPa and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain particleboard.

[0083] Comparative Example 2

[0084] This comparative example is a method for preparing activated carbon formaldehyde-removing particleboard, including the following steps:

[0085] S1. Preparation of active lignin

[0086] Step A: Add 2g of lignin to 25mL of phosphoric acid-sulfuric acid mixed solution, soak for 1 hour, and then filter to obtain the filter residue;

[0087] Step B: Take the filter residue, heat it at 300°C for 6 hours, cool it, and then heat it at 600°C for 2 hours to obtain intermediate product I;

[0088] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 40-mesh sieve to obtain the active lignin. Take 7 g of diatomaceous earth and mix it with the obtained active lignin to obtain the active lignin-diatomaceous earth complex.

[0089] S2. Take 2g of active lignin-diatomaceous earth composite, 8g of epoxy resin e44 and 90g of fine wood shavings and stir them evenly to obtain surface slurry.

[0090] S3. Take 2g of active lignin-diatomaceous earth composite, 8g of epoxy resin e44 and 90g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0091] S4. Take 1g of isocyanate curing agent and add it to each of the surface slurry, core slurry and surface slurry. Lay them in layers in sequence, and hot press them to form. The hot pressing temperature is 200℃, the pressure is 3MPa and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain particleboard.

[0092] Comparative Example 3

[0093] This comparative example is a method for preparing activated carbon formaldehyde-removing particleboard, including the following steps:

[0094] S1. Preparation of active lignin-active diatomite complex

[0095] Step A: Add 7g of diatomaceous earth and 2g of lignin to 25mL of 30wt% sulfuric acid solution, soak for 1 hour, and then filter to obtain the filter residue.

[0096] Step B: Take the filter residue, heat it at 300°C for 6 hours, cool it, and then heat it at 600°C for 2 hours to obtain intermediate product I;

[0097] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 40-mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0098] S2. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of fine wood shavings and stir them evenly to obtain the surface slurry.

[0099] S3. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0100] S4. Take 1g of isocyanate curing agent and add it to each of the surface slurry, core slurry and surface slurry. Lay them in layers in sequence, and hot press them to form. The hot pressing temperature is 200℃, the pressure is 3MPa and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain particleboard.

[0101] Comparative Example 4

[0102] This comparative example is a method for preparing activated carbon formaldehyde-removing particleboard, including the following steps:

[0103] S1. Preparation of active lignin-active diatomite complex

[0104] Step A: Add 7g of diatomaceous earth and 2g of lignin to 25mL of 10wt% phosphoric acid solution, soak for 1 hour, and then filter to obtain the filter residue.

[0105] Step B: Take the filter residue, heat it at 300°C for 6 hours, cool it, and then heat it at 600°C for 2 hours to obtain intermediate product I;

[0106] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 40-mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0107] S2. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of fine wood shavings and stir them evenly to obtain the surface slurry.

[0108] S3. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0109] S4. Take 1g of isocyanate curing agent and add it to each of the surface slurry, core slurry and surface slurry. Lay them in layers in sequence, and hot press them to form. The hot pressing temperature is 200℃, the pressure is 3MPa and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain particleboard.

[0110] Comparative Example 5

[0111] This comparative example is a method for preparing activated carbon formaldehyde-removing particleboard, including the following steps:

[0112] S1. Preparation of active lignin-active diatomite complex

[0113] Step A: Add 7g of diatomaceous earth and 2g of lignin to 25mL of phosphoric acid-sulfuric acid mixed solution, soak for 1 hour, and then filter to obtain the filter residue;

[0114] Step B: Take the filter residue, heat it at 300°C for 6 hours, rapidly increase the temperature to 600°C, and heat it at 600°C for 2 hours to obtain intermediate product I;

[0115] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 40-mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0116] S2. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of fine wood shavings and stir them evenly to obtain the surface slurry.

[0117] S3. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0118] S4. Take 1g of isocyanate curing agent and add it to each of the surface slurry, core slurry and surface slurry. Lay them in layers in sequence, and hot press them to form. The hot pressing temperature is 200℃, the pressure is 3MPa and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain particleboard.

[0119] Comparative Example 6

[0120] This comparative example is a method for preparing activated carbon formaldehyde-removing particleboard, including the following steps:

[0121] S1. Preparation of active lignin-active diatomite complex

[0122] Step A: Add 7g of diatomaceous earth and 2g of lignin to 25mL of phosphoric acid-sulfuric acid mixed solution, soak for 1 hour, and then filter to obtain the filter residue;

[0123] Step B: Take the filter residue, heat it at 300°C for 6 hours, cool it, and then heat it at 600°C for 2 hours to obtain intermediate product I;

[0124] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 40-mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0125] S2. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e51 and 90g of fine wood shavings and stir them evenly to obtain surface slurry.

[0126] S3. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e51 and 90g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0127] S4. Take 1g of isocyanate curing agent and add it to each of the surface slurry, core slurry and surface slurry. Lay them in layers in sequence, and hot press them to form. The hot pressing temperature is 200℃, the pressure is 3MPa and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain particleboard.

[0128] Comparative Example 7

[0129] This comparative example is a method for preparing activated carbon formaldehyde-removing particleboard, including the following steps:

[0130] S1. Preparation of active lignin-active diatomite complex

[0131] Step A: Add 7g of diatomaceous earth and 2g of lignin to 25mL of phosphoric acid-sulfuric acid mixed solution, soak for 1 hour, and then filter to obtain the filter residue;

[0132] Step B: Take the filter residue, heat it at 300°C for 6 hours, cool it, and then heat it at 600°C for 2 hours to obtain intermediate product I;

[0133] Step C: Take 100 mL of 0.1 mol / L hydrochloric acid to wash intermediate product I 3 times, then wash with distilled water until the residual liquid is free of chloride ions, dry at 400℃, cool and pass through a 40-mesh sieve to obtain the active lignin-active diatomaceous earth composite.

[0134] S2. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of fine wood shavings and stir them evenly to obtain the surface slurry.

[0135] S3. Take 2g of active lignin-active diatomaceous earth composite, 8g of epoxy resin e44 and 90g of coarse wood shavings and stir them evenly to obtain core layer slurry.

[0136] S4. Take the surface slurry, core slurry and surface slurry and add 1g of curing agent T31 to each, lay them in layers in sequence, and hot press them into shape. The hot pressing temperature is 200℃, the pressure is 3MPa and the hot pressing time is 3min. After hot pressing, let it stand at room temperature for 24h to obtain particleboard.

[0137] Activated carbon formaldehyde-removing particleboard with dimensions of 2440mm×1220mm×10mm was prepared using the methods described in Examples 1-4 and Comparative Examples 1-7. The static bending strength (MOR), modulus of elasticity (MOE), internal bonding strength, 24h absorption thickness expansion rate, and formaldehyde purification efficiency of the activated carbon formaldehyde-removing particleboard prepared in each example and comparative example were measured under dry conditions. The results are shown in Table 1.

[0138] Table 1. Summary of Test Results for Activated Carbon Formaldehyde-Removing Particleboard

[0139]

[0140] As shown in Table 1, the activated carbon formaldehyde-removing particleboard prepared in Examples 1-4 has good physical and mechanical properties. According to GB / T 4897-2015, the activated carbon formaldehyde-removing particleboard prepared in Examples 1-4 meets the requirements of heavy-duty particleboard (P4 type) used in a dry state.

[0141] In Comparative Example 1, only activated diatomaceous earth and unactivated lignin were added, resulting in a decrease in the mechanical properties and formaldehyde purification efficiency of the particleboard. Activated lignin, obtained by soaking lignin in a phosphoric acid-sulfuric acid mixed solution and then heating it, can improve the adhesive properties of epoxy resin E44. Activated lignin also has a certain adsorption capacity, which can improve the formaldehyde purification efficiency of the particleboard.

[0142] In Comparative Example 2, only active lignin and unactivated diatomaceous earth were added, which reduced the mechanical properties and formaldehyde purification efficiency of the particleboard. Activated diatomaceous earth, which is obtained by soaking diatomaceous earth in a phosphoric acid-sulfuric acid mixed solution and then heating it, can also improve the adhesive properties of epoxy resin E44. Activated diatomaceous earth also has a certain adsorption effect, which can improve the formaldehyde purification efficiency of particleboard.

[0143] In Comparative Examples 3 and 4, the particleboard produced by soaking in sulfuric acid solution or phosphoric acid solution in step A showed a decrease in mechanical properties and a significant decrease in formaldehyde purification efficiency. Soaking in a mixed phosphoric acid-sulfuric acid solution can enhance the activation performance of diatomaceous earth and lignin.

[0144] In step B of Comparative Example 5, after the first addition was completed, the temperature was rapidly increased before the second addition was carried out without cooling. The mechanical properties of the particleboard produced by this method decreased slightly, but the formaldehyde purification efficiency decreased significantly. Cooling and then heating again can improve the adsorption capacity of diatomaceous earth and lignin.

[0145] Comparative Example 6 uses epoxy resin e51 as an adhesive. The formaldehyde purification efficiency of the resulting particleboard is not affected, but the mechanical properties are significantly reduced. This may be related to the properties of epoxy resin e51 itself, or it may be related to the fact that the active lignin-active diatomaceous earth composite cannot improve the adhesiveness of epoxy resin e51.

[0146] In Comparative Example 7, T31 was selected as the curing agent, and the resulting particleboard had good mechanical properties, but the formaldehyde purification efficiency was slightly reduced. T31 curing agent is a phenolic amine (PAA) epoxy curing agent with comprehensive performance, and this type of curing agent will affect the formaldehyde purification efficiency of the particleboard.

[0147] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A method for the production of diatomaceous aldehyde shaving board, characterized by, It comprises the following steps: S1, preparing active lignin-active diatomite compound; it comprises the following steps: A, taking 7-8 parts by weight of diatomite and 2-3 parts by weight of lignin into a mixed solution of phosphoric acid-sulfuric acid, filtering after soaking, and obtaining filter residue; B, taking the filter residue, heating at 300-400℃ for 6-8h, cooling, and heating at 600-700℃ for 2-3h to obtain intermediate product I; C, washing the intermediate product I with hydrochloric acid, washing with water until the residual liquid is free of chloride ions, drying at 400-500℃, and sieving through a 40-60 mesh sieve to obtain the active lignin-active diatomite compound; S2, stirring the active lignin-active diatomite compound, epoxy resin adhesive, and fine wood shaving uniformly to obtain surface layer slurry; S3, stirring the active lignin-active diatomite compound, epoxy resin adhesive, and coarse wood shaving uniformly to obtain core layer slurry; S4, adding curing agent to the surface layer slurry, core layer slurry, and surface layer slurry in sequence, layering in sequence, and hot pressing to form diatomite formaldehyde shaving board.

2. A process for the preparation of diatomic aldehyde shaving board according to claim 1, characterized in that, In step A, the preparation method of the mixed solution of phosphoric acid-sulfuric acid is as follows: Mixing 20 parts by volume of 30wt% sulfuric acid solution and 10 parts by volume of 10wt% phosphoric acid solution to obtain the mixed solution of phosphoric acid-sulfuric acid; The amount of the mixed solution of phosphoric acid-sulfuric acid is 25-30 parts by volume; The ratio of parts by weight to parts by volume is g:mL.

3. A process for the production of diatomic purified aldehyde shaving board according to claim 1 or 2, characterized in that, In step C, the concentration of the hydrochloric acid is 0.1mol / L, 100 parts by volume of the hydrochloric acid is used for each washing, and the number of washing times is 3-4 times.

4. A process for the preparation of diatomic aldehyde shaving board as claimed in claim 1, wherein, In step S2, the amount of the active lignin-active diatomite compound is 2-4 parts by weight, the amount of the epoxy resin adhesive is 8-12 parts by weight, and the amount of the fine wood shaving is 84-90 parts by weight.

5. A process for the preparation of diatomic aldehyde shaving board according to claim 1 or 4, characterized in that, In step S3, the amount of the active lignin-active diatomite compound is 2-4 parts by weight, the amount of the epoxy resin adhesive is 8-12 parts by weight, and the amount of the coarse wood shaving is 84-90 parts by weight.

6. A process for the production of diatomic purified aldehyde shaving board according to any one of claims 1-2 and 4, characterized by, In steps S2 and S3, the epoxy resin adhesive is epoxy resin e44.

7. A process for the production of diatomaceous aldehyde shaving board according to any one of claims 1-2 and 4, characterized in that, In step S4, the curing agent is isocyanate curing agent, and the amount of the curing agent is 1-2 parts by weight.

8. A process for the production of diatomic purified aldehyde shaving board according to any one of claims 1-2 and 4, characterized by, In step S4, the temperature of the hot pressing is 200-220℃, and the pressure is 3-5MPa.

9. A diatomaceous aldehyde-free shaving board, characterized by The diatomite formaldehyde shaving board is prepared by the preparation method of any one of claims 1-8.

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