A method for preparing plastic particles using waste aluminum-plastic composite

Abstract

The present application belongs to the technical field of plastic particle recycling and preparation, and relates to a method for preparing plastic particles from waste aluminum-plastic composite. The addition of fatty alcohol polyoxyethylene ether can cause the breaking of bubbles during the separation of aluminum and plastic, and the hydrophobic end of the quaternary ammonium cationic surfactant can be distributed on the surface of the bubbles, so that the hydrophobic end becomes hydrophilic and enters the water phase, thereby achieving the effect of defoaming. Under the adsorption bridging and adsorption electric neutralization of the quaternary ammonium cationic surfactant, the dye molecules can be destabilized and separated from water, thereby achieving the effect of decolorizing the dye molecules on the surface of the plastic, and greatly reducing the content of impurities on the surface of the separated aluminum and plastic. The preparation method is simple, the prepared plastic particles have few impurities, and the method is suitable for large-scale environmental protection industrial production.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of plastic particle recycling and preparation, and relates to a method for preparing plastic particles from waste aluminum-plastic composites. BACKGROUND

[0002] With the rapid development of China's economy, the industrialization and urbanization process is accelerating, and the resource consumption is increasing year by year, so the environmental pressure and resource bottleneck are becoming increasingly prominent. In recent years, the consumption level of paper-plastic-aluminum composite packaging has gradually increased, and the proportion of paper-plastic-aluminum composite packaging in municipal solid waste is becoming larger and larger.

[0003] Since the paper-plastic-aluminum composite packaging is still mixed in household garbage, it is difficult to be classified and recycled separately, and a perfect garbage classification mechanism has not been formed in China so far, and the raw materials of paper-plastic-aluminum are long fiber pulp, polyethylene and high-quality aluminum foil, which have good recycling value after being used once. However, the plastic particles obtained by the current film granulation contain many dye impurities, which limits the application of the plastic particles. SUMMARY

[0004] The purpose of the present application is to solve the above-mentioned problems existing in the prior art, and a method for preparing plastic particles from waste aluminum-plastic composites is provided.

[0005] The purpose of the present application can be realized by the following technical scheme: a method for preparing plastic particles from waste aluminum-plastic composites, the method comprising the following steps: preheating the waste aluminum-plastic composite, while introducing a softening gas, then adding an aluminum-plastic separating agent for uniform stirring, then performing aluminum-plastic separation, then performing centrifugal crushing, and finally performing extrusion granulation.

[0006] In the above-mentioned method for preparing plastic particles from waste aluminum-plastic composites, the preheating temperature is 100-120 DEG C, and the time is 3-5 h.

[0007] In the above-mentioned method for preparing plastic particles from waste aluminum-plastic composites, the softening gas is water vapor.

[0008] In the above-mentioned method for preparing plastic particles from waste aluminum-plastic composites, the mass ratio of the waste aluminum-plastic composite to the aluminum-plastic separating agent is (3-5): 1.

[0009] In the above-mentioned method for preparing plastic particles from waste aluminum-plastic composites, the aluminum-plastic separating agent comprises the following raw materials in mass fraction: 50-80 parts of sodium bicarbonate, 15-18 parts of sodium percarbonate, 20-30 parts of ethanol, 8-10 parts of fatty alcohol polyoxyethylene ether, 5-8 parts of bleaching agent, 0.05-0.1 parts of quaternary ammonium cationic surfactant, and 100-150 parts of water.

[0010] The addition of the fatty alcohol polyoxyethylene ether can cause the bubble to break in the aluminum-plastic separation process, and after being distributed on the surface of the bubble, the hydrophobic end of the quaternary ammonium cationic surfactant is attracted, so that it becomes hydrophilic and enters the water phase, thereby achieving the effect of defoaming.

[0011] In the method for preparing plastic particles from waste aluminum-plastic composite, the pH of the aluminum-plastic separation agent is 7.5-8.

[0012] In the method for preparing plastic particles from waste aluminum-plastic composite, the bleaching agent is sodium perborate.

[0013] In the method for preparing plastic particles from waste aluminum-plastic composite, the temperature in the extrusion granulation process is 150-180℃, and the time is 3-5h.

[0014] Compared with the prior art, the present application has the following beneficial effects: the addition of the fatty alcohol polyoxyethylene ether can cause the bubble to break in the aluminum-plastic separation process, and after being distributed on the surface of the bubble, the hydrophobic end of the quaternary ammonium cationic surfactant is attracted, so that it becomes hydrophilic and enters the water phase, thereby achieving the effect of defoaming. The quaternary ammonium cationic surfactant can make the dye molecules unstable and separate from water under the action of adsorption bridging and adsorption electric neutralization, thereby achieving the effect of decolorizing the dye molecules on the surface of the plastic and greatly reducing the impurity content on the surface of the separated aluminum-plastic. The preparation method is simple, the prepared plastic particles have less impurities, and is suitable for large-scale environmental protection industrial production. DETAILED DESCRIPTION

[0015] The following is a specific embodiment of the present application, which further describes the technical solutions of the present application, but the present application is not limited to these embodiments.

[0016] Example 1:

[0017] 480kg of waste aluminum-plastic composite was preheated at 120℃ for 5h while water vapor was introduced, then a separation agent was added in a mass ratio of 4:1 for uniform stirring, then aluminum-plastic separation was performed, then centrifugal crushing was performed, and finally extrusion granulation was performed in a double screw extruder, the temperature in the extrusion granulation process was 180℃, and the time was 4h.

[0018] The separation agent is composed of the following raw materials in mass fraction: 60 parts of sodium bicarbonate, 16 parts of sodium percarbonate, 25 parts of ethanol, 8 parts of fatty alcohol polyoxyethylene ether, 6 parts of sodium perborate, 0.08 parts of quaternary ammonium cationic surfactant, and 120 parts of water.

[0019] Example 2:

[0020] 480kg waste aluminum plastic composite is preheated at 120℃ for 5h while water vapor is passed in, then a separating agent is added in a mass ratio of 4:1 for uniform stirring, then aluminum plastic separation is carried out, then centrifugal crushing is carried out, and finally, extrusion granulation is carried out in a double screw extruder, the temperature in the extrusion granulation process is 180℃, and the time is 4h.

[0021] The separating agent is composed of the following mass fractions of raw materials: 50 parts of sodium bicarbonate, 15 parts of sodium percarbonate, 20 parts of ethanol, 8 parts of fatty alcohol polyoxyethylene ether, 5 parts of sodium perborate, 0.05 parts of quaternary ammonium cationic surfactant, and 100 parts of water.

[0022] Example 3:

[0023] 480kg waste aluminum plastic composite is preheated at 120℃ for 5h while water vapor is passed in, then a separating agent is added in a mass ratio of 4:1 for uniform stirring, then aluminum plastic separation is carried out, then centrifugal crushing is carried out, and finally, extrusion granulation is carried out in a double screw extruder, the temperature in the extrusion granulation process is 180℃, and the time is 4h.

[0024] The separating agent is composed of the following mass fractions of raw materials: 80 parts of sodium bicarbonate, 18 parts of sodium percarbonate, 30 parts of ethanol, 10 parts of fatty alcohol polyoxyethylene ether, 8 parts of sodium perborate, 0.1 parts of quaternary ammonium cationic surfactant, and 150 parts of water.

[0025] Table 1: Aluminum plastic separation results of examples 1-3

[0026] Example Plastic isolated (kg) Plastic impurity content (%) Example 1 350.16 0.23％ Example 2 349.3 0.25％ Example 3 345.19 0.26％

[0027] In summary, the addition of fatty alcohol polyoxyethylene ether in the present application can cause the breaking of bubbles during the aluminum plastic separation process, and after distribution on the surface of the bubbles, it can attract the hydrophobic end of the quaternary ammonium cationic surfactant, making it hydrophilic and entering the water phase, thereby achieving the effect of defoaming. At the same time, the ether bond in the fatty alcohol polyoxyethylene ether is not easily destroyed by acid or alkali, has high stability, is easily biodegradable, and will not cause additional pollution. The quaternary ammonium cationic surfactant in the present application can make the dye molecules unstable and separate from water under the action of adsorption bridging and adsorption electric neutralization, thereby achieving the effect of decolorizing the dye molecules on the surface of the plastic, greatly reducing the impurity content on the surface of the separated aluminum plastic.

[0028] The embodiments of the present application do not exhaust the technical range of the claimed technical scope of the present application, and the new technical solutions formed by the same or multiple technical features in the technical solutions of the embodiments are also within the scope of the claimed technical scope of the present application. Meanwhile, in all the listed or unlisted embodiments of the present application, the parameters in the same embodiment only represent one example (i.e. one feasible solution) of the technical solution, and there is no strict cooperation and limitation relationship between the parameters, wherein the parameters can be replaced with each other without violating the axioms and the statements of the present application, except for the specifically declared.

[0029] The technical means disclosed in the technical solutions of the present application is not limited to the technical means disclosed in the above technical means, and also includes the technical solutions composed of any combination of the above technical features. The above is the specific implementation of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements are also considered within the scope of the present application.

[0030] The specific embodiments described herein are merely illustrative of the present application. Those skilled in the art can make various modifications or supplements to the described specific embodiments or adopt similar ways to replace them, without departing from the spirit of the present application or exceeding the scope defined by the appended claims.

Claims

1. A method for preparing plastic granules using waste aluminum-plastic composites, characterized in that, The method includes the following steps: preheating the waste aluminum-plastic composite while introducing softening gas, then adding an aluminum-plastic separator and stirring evenly, then separating the aluminum and plastic, then centrifuging and crushing, and finally extruding and granulating. The preheating temperature is 100-120℃, and the time is 3-5 hours; The softened gas is water vapor; The mass ratio of waste aluminum-plastic composite to aluminum-plastic separator is (3-5):1; The aluminum-plastic separator comprises the following raw materials in the following mass fractions: 50-80 parts sodium bicarbonate, 15-18 parts sodium percarbonate, 20-30 parts ethanol, 8-10 parts fatty alcohol polyoxyethylene ether, 5-8 parts bleaching agent, 0.05-0.1 parts quaternary ammonium cationic surfactant, and 100-150 parts water; The pH of the aluminum-plastic separator is 7.5-8; The bleaching agent is sodium perborate; The temperature during the extrusion granulation process is 150-180℃, and the time is 3-5 hours.