Preparation method of tea adsorbent

Abstract

The invention discloses a preparation method of a tea adsorbent, which comprises the following steps: putting 40-400 parts of activated carbon powder, 14-350 parts of sodium persulfate and 2-50 parts of ferrous sulfate into a mixing stirrer, and carrying out high-speed mixing and stirring at normal temperature for 15-45 minutes to obtain a mixed solution; 5-50 parts of a binder is taken, the binder is composed of calcium chloride, starch and methyl cellulose, the mass ratio of the calcium chloride to the starch to the methyl cellulose is 1: 1: 1, 8 times by weight of water is added into the binder, the mixture is stirred to be uniform, and a binder solution is obtained and stands for use; putting the mixed solution into a granulator, adding a binder solution, fully stirring for 5-20 minutes, and carrying out rapid binding granulation for 1 minute to obtain wet particles of the tea adsorbent; and drying the wet particles of the tea adsorbent, and calcining for 30-60 minutes at a high temperature of 300 DEG C to obtain the tea adsorbent. The tea adsorbent prepared by the preparation method disclosed by the invention can effectively adsorb indoor formaldehyde.

Description

Technical Field

[0001] The invention relates to the technical field of activated carbon, and in particular to a method for preparing a tea adsorbent. Background Art

[0002] Whether tea is used as a beverage or to extract active substances such as tea polysaccharides and tea polyphenols, a large amount of industrial tea residue is produced, most of which are discarded as waste in the environment, causing a huge waste of resources. Tea residue contains a large amount of cellulose, hemicellulose, lignin, trace elements, etc., and is an ideal biomass precursor for preparing biochar. In addition to the advantage of a wide range of raw material sources, tea residue is one of the sources of plant raw materials. The physical and chemical properties of the prepared biochar, such as specific surface area and pore structure, are superior to other types of biochar. It can be used to adsorb pollutants in water, remove heavy metals, purify the air, etc. Therefore, preparing biochar with tea residue as raw material is one of the important ways to utilize its resources, and has broad application prospects.

[0003] Referring to an activated carbon adsorbent with good formaldehyde removal and odor removal effect disclosed in Chinese invention patent application CN104941605A, the carbon content of the sludge is increased by adding corn stalks and peanut shells to the sludge, the adsorption of the sludge is improved, and the activated carbon is activated by modifying zinc chloride with silicon dioxide and magnesium silicate, the number of pores of the sludge activated carbon is increased, and the adsorption performance and bactericidal property are improved. However, the formaldehyde adsorption rate of the adsorbent prepared by the above invention is low, which is 65%, and the effect of removing formaldehyde is poor, resulting in a high formaldehyde concentration in the air, and the air purification effect cannot be achieved. Summary of the invention

[0004] The invention provides a method for preparing a tea adsorbent, aiming to solve the problems that the existing adsorbent has a low formaldehyde adsorption rate and cannot achieve the air purification effect.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: A method for preparing a tea adsorbent comprises the following steps: S1, put 40-400 parts of activated carbon powder, 14-350 parts of sodium persulfate, and 2-50 parts of ferrous sulfate into a mixing and stirring machine, and mix and stir at high speed at room temperature for 15-45 minutes to obtain a mixed solution; S2, take 5-50 parts of a binder, the binder is composed of calcium chloride, starch and methyl cellulose, the mass ratio of calcium chloride, starch and methyl cellulose is 1:1:1, add 8 times the weight of water to the binder, stir evenly to obtain a binder solution, and let it stand for use; S3, the mixed solution is put into a granulator, and then the binder solution is added, and after being fully stirred for 5 to 20 minutes, a quick bonding granulation is performed for 1 minute to obtain wet granules of the tea adsorbent; S4. Dry the wet particles of the tea adsorbent, and then calcine them at 300° C. for 30 to 60 minutes to obtain the tea adsorbent.

[0006] Furthermore, the activated carbon powder in the above S1 is prepared by the following steps: (1) Dry the tea residue powder at 105 °C to constant weight and store it in a desiccator; (2) Mix tea dregs powder and phosphoric acid in a weight ratio of 1:3 and soak at room temperature for 6 to 15 hours; (3) Put the tea residue powder and phosphoric acid mixture into a crucible, then move it to a muffle furnace, heat it up at a rate of 10 °C / min, and carbonize and activate it at 550 °C for 1 h. (4) After cooling the mixture obtained in step (3) to room temperature, pour it into a (1+9) hydrochloric acid aqueous solution, and then repeatedly rinse it with distilled water until the pH of the solution is neutral; (5) The solution obtained in step (4) is dried at 100°C and then crushed to 200 meshes using a pulverizer to obtain activated carbon powder.

[0007] Furthermore, the tea residue powder in the above step (1) is a powder of ≤40 mesh obtained by washing Tieguanyin tea leaves with pure water, air drying, crushing and sieving.

[0008] Furthermore, in the above step (2), the concentration of phosphoric acid is 35% to 60%.

[0009] From the above description of the structure of the present invention, it can be seen that the present invention has the following advantages: The present invention uses tea residue as a raw material to prepare activated carbon powder, which is combined with sodium persulfate and ferrous sulfate to prepare a tea adsorbent. The tea residue activated carbon has the advantages of a wide source of raw materials, and a specific surface area and a pore structure that are superior to other types of biochar. The adsorbent prepared by the present invention has a strong ability to remove formaldehyde in the environment and has broad application prospects.

[0010] The test found that the product of the present invention can remove formaldehyde in the environment at room temperature within 120 minutes at a rate of 91.6%, which is 26.6-53.4% ​​higher than ordinary activated carbon adsorbents on the market, and can effectively adsorb indoor formaldehyde. DETAILED DESCRIPTION

[0011] The specific implementation of the present invention is described below. In order to fully understand the present invention, many details are described below, but for those skilled in the art, the present invention can be implemented without these details. For well-known components, methods and processes, they are not described in detail below.

[0012] Embodiment 1 A method for preparing a tea adsorbent comprises the following steps: S1. Put 160 parts of activated carbon powder, 14 parts of sodium persulfate and 2 parts of ferrous sulfate into a mixing mixer, and mix and stir at high speed at room temperature for 30 minutes to obtain a mixed solution; S2, take 12 parts of the binder, add 8 times the weight of water to the binder, stir evenly to obtain a binder solution, and let it stand for use; S3, the mixed solution is put into a granulator, and then the binder solution is added, and after being fully stirred for 5 minutes, a quick bonding granulation is performed for 1 minute to obtain wet granules of the tea adsorbent; S4. Dry the wet particles of the tea adsorbent, and then calcine them at 300° C. for 30 minutes to obtain the tea adsorbent.

[0013] High-temperature calcination volatilizes the starch and cellulose in the binder through high temperature, so that the phosphorylated tea residue activated carbon is fully combined with other functional components adsorbed by it, and the original pore size is further expanded.

[0014] In step S1, the binder is made of calcium chloride, starch and methyl cellulose, and the mass ratio of calcium chloride, starch and methyl cellulose is 1:1:1.

[0015] The activated carbon powder in S1 is prepared by the following steps: (1) Dry the tea residue powder at 105 °C to constant weight and store it in a desiccator; (2) Mix tea residue powder and phosphoric acid in a weight ratio of 1:3 and soak at room temperature for 12 h; (3) Put the tea residue powder and phosphoric acid mixture into a crucible, then move it to a muffle furnace, heat it up at a rate of 10 °C / min, and carbonize and activate it at 550 °C for 1 h. (4) After cooling the mixture obtained in step (3) to room temperature, pour it into a (1+9) hydrochloric acid aqueous solution, and then repeatedly rinse it with distilled water until the pH of the solution is neutral; (5) The solution obtained in step (4) is dried at 100°C and then crushed to 200 meshes using a pulverizer to obtain activated carbon powder.

[0016] The tea residue powder in step (1) is a powder of less than or equal to 40 mesh obtained by washing, air-drying, crushing and sieving Tieguanyin tea corners with pure water. From an economic point of view, in order to select a phosphoric acid concentration with a higher yield and more products, the phosphoric acid concentration in step (2) is fixed at 45%. The tea adsorbent prepared in the embodiment can remove formaldehyde in the environment at room temperature within 120 minutes. The removal rate can reach 91.6%.

[0017] Embodiment 2 A method for preparing a tea adsorbent comprises the following steps: S1, put 80 parts of activated carbon powder, 7 parts of sodium persulfate, and 1 part of ferrous sulfate into a mixing mixer, and mix and stir at high speed at room temperature for 30 minutes to obtain a mixed solution; S2, take 6 parts of the binder, add 8 times the weight of water to the binder, stir evenly to obtain a binder solution, and let it stand for use; S3, the mixed solution is put into a granulator, and then the binder solution is added, and after being fully stirred for 10 minutes, a quick bonding granulation is performed for 1 minute to obtain wet granules of the tea adsorbent; S4. Dry the wet particles of the tea adsorbent, and then calcine them at 300° C. for 45 minutes to obtain the tea adsorbent.

[0018] High-temperature calcination volatilizes the starch and cellulose in the binder through high temperature, so that the phosphorylated tea residue activated carbon is fully combined with other functional components adsorbed by it, and the original pore size is further expanded.

[0019] In step S1, the binder is made of calcium chloride, starch and methyl cellulose, and the mass ratio of calcium chloride, starch and methyl cellulose is 1:1:1.

[0020] The activated carbon powder in S1 is prepared by the following steps: (1) Dry the tea residue powder at 105 °C to constant weight and store it in a desiccator; (2) Mix tea residue powder and phosphoric acid in a weight ratio of 1:3 and soak at room temperature for 12 h, where the phosphoric acid concentration is 31%; (3) Put the tea residue powder and phosphoric acid mixture into a crucible, then move it to a muffle furnace, heat it up at a rate of 10 °C / min, and carbonize and activate it at 550 °C for 1 h. (4) After cooling the mixture obtained in step (3) to room temperature, pour it into a (1+9) hydrochloric acid aqueous solution, and then repeatedly rinse it with distilled water until the pH of the solution is neutral; (5) The solution obtained in step (4) is dried at 100°C and then crushed to 200 meshes using a pulverizer to obtain activated carbon powder.

[0021] Embodiment 3 A method for preparing a tea adsorbent comprises the following steps: S1, put 320 parts of activated carbon powder, 28 parts of sodium persulfate, and 4 parts of ferrous sulfate into a mixing mixer, and mix and stir at high speed at room temperature for 45 minutes to obtain a mixed solution; S2, take 21 parts of the binder, add 8 times the weight of water to the binder, stir evenly to obtain a binder solution, and let it stand for use; S3, the mixed solution is put into a granulator, and then the binder solution is added, and after being fully stirred for 20 minutes, a quick bonding granulation is performed for 1 minute to obtain wet granules of the tea adsorbent; S4. Dry the wet particles of the tea adsorbent, and then calcine them at 300° C. for 30 minutes to obtain the tea adsorbent.

[0022] High-temperature calcination volatilizes the starch and cellulose in the binder through high temperature, so that the phosphorylated tea residue activated carbon is fully combined with other functional components adsorbed by it, and the original pore size is further expanded.

[0023] In step S1, the binder is made of calcium chloride, starch and methyl cellulose, and the mass ratio of calcium chloride, starch and methyl cellulose is 1:1:1.

[0024] The activated carbon powder in S1 is prepared by the following steps: (1) Dry the tea residue powder at 105 °C to constant weight and store it in a desiccator; (2) Mix tea residue powder and phosphoric acid in a weight ratio of 1:3 and soak at room temperature for 12 h, where the phosphoric acid concentration is 50%; (3) Put the tea residue powder and phosphoric acid mixture into a crucible, then move it to a muffle furnace, heat it up at a rate of 10 °C / min, and carbonize and activate it at 550 °C for 1 h. (4) After cooling the mixture obtained in step (3) to room temperature, pour it into a (1+9) hydrochloric acid aqueous solution, and then repeatedly rinse it with distilled water until the pH of the solution is neutral; (5) The solution obtained in step (4) is dried at 100°C and then crushed to 200 meshes using a pulverizer to obtain activated carbon powder.

[0025] The above is only a specific implementation of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial changes to the present invention using this concept shall be deemed as an infringement of the protection scope of the present invention.

Claims

1. A method for preparing a tea adsorbent, characterized in that: The following steps are involved: S1, put 40-400 parts of activated carbon powder, 14-350 parts of sodium persulfate, and 2-50 parts of ferrous sulfate into a mixing and stirring machine, and mix and stir at high speed at room temperature for 15-45 minutes to obtain a mixed solution; S2, take 5-50 parts of a binder, the binder is composed of calcium chloride, starch and methyl cellulose, the mass ratio of calcium chloride, starch and methyl cellulose is 1:1:1, add 8 times the weight of water to the binder, stir evenly to obtain a binder solution, and let it stand for use; S3, the mixed solution is put into a granulator, and then the binder solution is added, and after being fully stirred for 5 to 20 minutes, a quick bonding granulation is performed for 1 minute to obtain wet granules of the tea adsorbent; S4. Dry the wet particles of the tea adsorbent, and then calcine them at 300° C. for 30 to 60 minutes to obtain the tea adsorbent.

2. The method for preparing the tea adsorbent according to claim 1, characterized in that: The activated carbon powder described in S1 is prepared by the following steps: (1) Dry the tea residue powder at 105 °C to constant weight and store it in a desiccator; (2) Mix tea dregs powder and phosphoric acid in a weight ratio of 1:3 and soak at room temperature for 6 to 15 hours; (3) Put the tea residue powder and phosphoric acid mixture into a crucible, then move it to a muffle furnace, heat it up at a rate of 10 °C / min, and carbonize and activate it at 550 °C for 1 h. (4) After cooling the mixture obtained in step (3) to room temperature, pour it into a (1+9) hydrochloric acid aqueous solution, and then repeatedly rinse it with distilled water until the pH of the solution is neutral; (5) The solution obtained in step (4) is dried at 100°C and then crushed to 200 meshes using a pulverizer to obtain activated carbon powder.

3. The method for preparing the tea adsorbent according to claim 2, characterized in that: In step (1), the tea residue powder is obtained by washing Tieguanyin tea leaves with pure water, air drying, crushing and sieving to obtain a powder with a mesh size of less than or equal to 40.

4. The method for preparing the tea adsorbent according to claim 2, characterized in that: The concentration of phosphoric acid in step (2) is 35% to 60%.