Waste potato-derived fulvic acid slow-release fully-degradable mulching film as well as preparation method and application thereof

Abstract

The invention provides a waste potato-derived fulvic acid slow-release full-degradable mulching film as well as a preparation method and application thereof, and belongs to the technical field of agricultural environment. Waste potatoes are prepared into a solution, then the solution is compounded with potassium sulfate, tartaric acid and fulvic acid according to a certain proportion to form a mixed solution, and the waste potato source fulvic acid slow-release type fully-degradable mulching film is prepared through uniform spreading and microwave irradiation. According to the invention, resource utilization of the waste potatoes is realized; meanwhile, the prepared mulching film is good in mechanical performance, and the actual application requirement is met. The prepared mulching film has good heat preservation and soil moisture conservation effects, fulvic acid is slowly released, and the film-fertilizer dual-function effect is achieved. In addition, after the mulching film is degraded, soil components are improved.

Description

Technical Field

[0001] This invention relates to a slow-release, fully degradable mulch film derived from waste potatoes, its preparation method, and its application, belonging to the field of agricultural environmental technology. Background Technology

[0002] Used plastic film is prone to aging and breakage, and is difficult to recycle (less than 66.67%), easily causing white pollution. Therefore, there is an urgent need to develop biodegradable plastic film to replace traditional polyethylene plastic film.

[0003] Meanwhile, potatoes are an important global crop and one of the world's most important staple crops. It is estimated that approximately 450,000 tons of potatoes are discarded annually, mostly at the household level. This not only wastes resources but also causes serious environmental pollution, urgently requiring the development of new methods for resource utilization. Because potatoes are rich in starch (approximately 12%-25%), carbohydrates (approximately 17%), protein (approximately 2.5%), and lipids (approximately 0.2%), and are rich in potassium and iron, they could be processed into a slow-release, fully biodegradable mulch film, maximizing their nutritional value while simultaneously addressing the pollution problems associated with traditional polyethylene mulch films. Summary of the Invention

[0004] The purpose of this invention is to solve the problem of aging and fragility of plastic film, which is difficult to recycle in the prior art.

[0005] To address the aforementioned problems, the present invention provides a slow-release, fully degradable mulch film derived from waste potatoes, along with its preparation method and application.

[0006] In a first aspect, the present invention provides a method for preparing a slow-release, fully degradable mulch film derived from waste potatoes, comprising the following steps: Step 1): Cut the waste potatoes into pieces and crush them into liquid waste potatoes; Step 2): Add deionized water to the liquid waste potatoes obtained in Step 1) by stirring to obtain a waste potato solution; Step 3): Add potassium sulfate, tartaric acid and fulvic acid to the waste potato solution obtained in Step 2) by stirring to obtain a mixed solution; Step 4): Spread the mixed solution obtained in Step 3) evenly on a ceramic plate, and after microwave irradiation, directly form a waste potato-derived slow-release fully degradable mulch film.

[0007] Preferably, in step 2), the mass of liquid waste potatoes is 100-200g; the volume of deionized water is 50-100mL; the stirring temperature is 20-30℃; the stirring speed is 100-200rpm; and the stirring time is 5-10 minutes.

[0008] Preferably, in step 3), the amount of potassium sulfate is 2-4g; the amount of tartaric acid is 2-4g; the amount of fulvic acid is 5-10g; the stirring temperature is 30-40℃; the stirring speed is 100-200rpm; and the stirring time is 10-20 minutes.

[0009] Preferably, the paving speed in step 4) is 0.2-0.4 L / min; the ceramic plate area is 1-2 m². 2 The microwave irradiation settings are 160W, 2450MHz; the irradiation time is 10-15 minutes; and the area of ​​the plastic film is 1-2m². 2 The thickness of the plastic film is 0.2-0.4 mm.

[0010] In a second aspect, the present invention provides a waste potato-derived slow-release fully degradable mulch film prepared by the above-described preparation method.

[0011] In a third aspect, the present invention provides an application of the above-mentioned waste potato-derived slow-release fully degradable mulch film in planting.

[0012] Compared with the prior art, the present invention has the following beneficial effects: This invention enables the resource utilization of waste potatoes; simultaneously, the prepared mulch film has good mechanical properties, meeting the needs of practical applications. The prepared mulch film not only has excellent heat preservation and moisture retention effects, but also slowly releases humic acid, playing a dual role as both a film and fertilizer. Furthermore, the degradation of the mulch film improves soil composition. Attached Figure Description

[0013] Figure 1 A diagram of a slow-release humic acid mulch film derived from waste potatoes provided by this invention; Figure 2 This is a comparison diagram of the mechanical properties of the mulch film prepared in Example 2 of the present invention and traditional plastic mulch film; Figure 3 Comparison of the plastic film prepared in Example 2 of the present invention, blank (without film), and traditional plastic film applied to the field for 0 days and 30 days; Figure 4 A comparison diagram showing the heat preservation effect of the mulch film prepared in Example 2 of the present invention; Figure 5 This is a comparison chart of plant germination rate and yield data for the mulch film prepared in Example 2 of the present invention; Figure 6 A comparison chart of plant height and root length data of the mulch film prepared in Example 2 of the present invention; Figure 7 Comparison of plant height and root length of the mulch film prepared in Example 2 of the present invention; Figure 8 The graph shows the slow-release humic acid curve of the mulch film prepared in Example 2 of this invention. Figure 9 Three-dimensional fluorescence images of the mulch film prepared in Example 2 of this invention at 0, 10, 20, 40, 60 and 70 days. Detailed Implementation

[0014] To make the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings: This invention provides a slow-release, fully degradable mulch film derived from waste potatoes, its preparation method, and its application. Waste potatoes are prepared into a solution, which is then mixed with potassium sulfate, tartaric acid, and fulvic acid in a specific ratio to form a mixed solution. This solution is then uniformly spread and microwave-irradiated to obtain the slow-release, fully degradable mulch film derived from waste potatoes. This invention achieves the resource utilization of waste potatoes; simultaneously, the prepared mulch film not only has good heat preservation and moisture retention effects but also slowly releases fulvic acid, playing a dual role as both a film and fertilizer. Furthermore, the degradation of the mulch film improves soil composition.

[0015] Example 1: (1) Cut the waste potatoes into pieces and crush them into liquid waste potatoes; (2) Take 100g of liquid waste potato, stir and add 50mL of deionized water, stir at 20-30℃ (100rpm) for 5 minutes to obtain waste potato solution; (3) Add 2g potassium sulfate, 2g tartaric acid and 5g fulvic acid to the waste potato solution obtained in (2) and stir at 30-40℃ (100rpm) for 10 minutes to obtain a mixed solution; (4) Spread the mixed solution obtained in (3) evenly on a 1m... 2 The ceramic plate was irradiated with microwaves (160W, 2450MHz) for 10 minutes, and then a film (1m) was directly formed. 2 (thickness 0.2mm) (5) The film was laid flat on the soil surface planted with Shanghai bok choy and covered with soil around it. The results of the harvest on the 30th day showed that compared with the uncovered group, the treatment increased the emergence rate of Shanghai bok choy by 42.8%, biomass by 215%, and plant height by 69.4%. It also increased the available nitrogen, available phosphorus, available potassium and organic matter in the soil by 23.4%, 14.4%, 13.3% and 18.2%, respectively. The humic acid was completely released in 60 days and the film was completely degraded in 120 days.

[0016] Example 2: (1) Cut the waste potatoes into pieces and crush them into liquid waste potatoes; (2) Take 150g of liquid waste potato, stir and add 75mL of deionized water, stir at 20-30℃ (200rpm) for 8 minutes to obtain waste potato solution; (3) Add 3g potassium sulfate, 3g tartaric acid and 7.5g fulvic acid to the waste potato solution obtained in (2) and stir at 30-40℃ (200 rpm) for 15 minutes to obtain a mixed solution; (4) Spread the mixed solution obtained in (3) evenly on a 1.5m... 2 The ceramic plate was irradiated with microwaves (160W, 2450MHz) for 12 minutes, and then a film (1.5m thick) was directly formed. 2 (thickness 0.3mm), such as Figure 1 As shown; the prepared mulch film has good mechanical properties (e.g. Figure 2 ), to meet the needs of practical applications; (5) Lay the film flat on the soil surface where Shanghai bok choy is planted, and cover it with soil around it, such as Figure 3 As shown; the heat preservation effect is better than that of traditional plastic film (e.g.) within 60 days. Figure 4 ); Harvest results on day 30 are as follows Figure 5-7 As shown: Compared with the uncovered group (blank), the group with flat-laid mulch film (product) showed a 59.9% higher emergence rate, a 235% increase in biomass, and a 108.3% increase in plant height in Shanghai bok choy. Soil available nitrogen, available phosphorus, available potassium, and organic matter increased by 37.6%, 51.7%, 45.7%, and 41.4%, respectively (as shown in Table 1). Fulvic acid was completely released within 70 days (e.g., ...). Figure 8 , Figure 9 The membrane completely degraded in 150 days.

[0017] Example 3: (1) Cut the waste potatoes into pieces and crush them into liquid waste potatoes; (2) Take 200g of liquid waste potato and add 100mL of deionized water. Stir at 20-30℃ (200 rpm) for 10 minutes to obtain waste potato solution; (3) Add 4g potassium sulfate, 4g tartaric acid and 10g fulvic acid to the waste potato solution obtained in (2) and stir at 30-40℃ (200 rpm) for 20 minutes to obtain a mixed solution; (4) Spread the mixed solution obtained in (3) evenly on a 2m... 2 The ceramic plate was irradiated with microwaves (160W, 2450MHz) for 15 minutes, and then a film (2m thick) was directly formed. 2 (thickness 0.4 mm). (5) The film was laid flat on the soil surface planted with Shanghai bok choy and covered with soil around it. The results of the harvest on the 30th day showed that compared with the uncovered group, the treatment increased the emergence rate of Shanghai bok choy by 45.9%, biomass by 220%, and plant height by 82.7%. It also increased the available nitrogen, available phosphorus, available potassium and organic matter in the soil by 31.1%, 23.7%, 17.8% and 21.1%, respectively. The humic acid was completely released in 80 days and the film was completely degraded in 180 days.

[0018] Among them, Example 2 showed the best results (it had the best effect on promoting soil growth and improvement). Table 1 shows a comparison of soil indicators using the mulch film prepared in Example 2, the blank (uncovered), and traditional plastic mulch film: Table 1. Comparison of soil indicators for the mulch film prepared using Example 2, blank (uncovered), and traditional plastic mulch film.

[0019] Application Example 1: The waste potato-derived slow-release fully degradable mulch film prepared in Example 2 was used in a field experiment. The prepared mulch film and traditional plastic mulch film were laid separately, and the soil without mulch film was used as a control experiment.

[0020] During the field experiment, the temperature and humidity of the soil 5cm below the surface were recorded at 18:00 every day, and the changes in temperature and humidity during this period were recorded.

[0021] Testing revealed that the soil temperature at a depth of 5 cm under the waste potato-derived slow-release humic acid fully degradable mulch was, on average, 0.36°C higher than that under no mulch and 0.13°C lower than that under traditional plastic mulch. Simultaneously, soil moisture under the mulch decreased more slowly than under no mulch. Furthermore, the fresh weight and plant height of Shanghai bok choy plants under the mulch were higher than those under both mulch and traditional plastic mulch. Notably, the root system of plants under the mulch was also longer than that under traditional plastic mulch, further demonstrating the release of nutrients such as humic acid from the prepared mulch. During the field experiment, rainfall in some weather conditions met the basic needs of plant growth, and degradation of the prepared mulch was also observed.

[0022] In summary, the waste potato-derived slow-release fulvic acid fully degradable mulch film of the present invention promotes plant growth, increases the content of available nitrogen, available phosphorus, available potassium and organic matter in the soil, slows down the release of fulvic acid, and the mulch film prepared in the end can be completely degraded.

[0023] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a slow-release, fully degradable mulch film derived from waste potatoes, characterized in that, Includes the following steps: Step 1): Cut the waste potatoes into pieces and crush them into liquid waste potatoes; Step 2): Add deionized water to the liquid waste potatoes obtained in Step 1) by stirring to obtain a waste potato solution; Step 3): Add potassium sulfate, tartaric acid and fulvic acid to the waste potato solution obtained in Step 2) by stirring to obtain a mixed solution; Step 4): Spread the mixed solution obtained in Step 3) evenly on a ceramic plate, and after microwave irradiation, directly form a waste potato-derived slow-release fully degradable mulch film.

2. The method for preparing the waste potato-derived slow-release fully degradable mulch film as described in claim 1, characterized in that, In step 2), the mass of liquid waste potatoes is 100-200g; the volume of deionized water is 50-100mL; the stirring temperature is 20-30℃; the stirring speed is 100-200rpm; and the stirring time is 5-10 minutes.

3. The method for preparing the waste potato-derived slow-release fully degradable mulch film as described in claim 1, characterized in that, In step 3), the amount of potassium sulfate is 2-4g; tartaric acid is 2-4g; fulvic acid is 5-10g; the stirring temperature is 30-40℃; the stirring speed is 100-200rpm; and the stirring time is 10-20 minutes.

4. The method for preparing the waste potato-derived slow-release fully degradable mulch film as described in claim 1, characterized in that, In step 4), the paving speed is 0.2-0.4 L / min; the area of ​​the ceramic plate is 1-2 m². 2 The microwave irradiation settings are 160W, 2450MHz; the irradiation time is 10-15 minutes; and the area of ​​the plastic film is 1-2m². 2 The thickness of the plastic film is 0.2-0.4 mm.

5. A waste potato-derived slow-release fully degradable mulch film prepared by the preparation method according to any one of claims 1-4.

6. The application of a waste potato-derived slow-release fully degradable mulch film as described in claim 5 in planting.

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