Study on Degradation of Foamed Plastic Meal Cases (2)

This experiment is divided into two parts: chemical biodegradation and solid-phase experiments, and the degradation of plastic fragments is observed. Chemical biodegradation is the use of the principle of similar dissolution of organic substances. First, the polystyrene lunch boxes are dissolved in a non-toxic aqueous solution of raspberry ketone or vanillin (8). In vivo use, so as to achieve the purpose of degradation. The solid-phase experiment, that is, the soil-buried experiment, is based on the weight loss and breakage of plastic fragments buried in the soil after a certain period of time as an indicator to assess the degradability. In this experiment, the solid phase was divided into soil buried and activated sludge landfill. The microorganisms in this experiment used well-run municipal sewage sludge as a microbiological provenance (9).

1. Chemical dissolution:
A: Benzene Molecular formula: C6H6
B: Raspberry Ketone Molecular formula: C10H12O2
C: Vanillin Molecular formula: C8H8O3
In this experiment, benzene was used as a comparative solvent to observe the solubility of polystyrene.
Principle of realization: Using the principle of similar compatibility of organic substances, the polystyrene lunch box is first dissolved in a solution containing non-toxic raspberry ketone or vanillin, and it is observed whether the microorganisms will eat the organic dispersion in the water to achieve degradation. The goal. Microorganisms were aerated for a period of two to three days with the sludge from the Tianshan Sewage Treatment Plant as the source of microorganisms. The supernatant was discarded and the gelatinous layer in the sludge was removed.

Solvent configuration: Take six 60ml beakers numbered E, F, G, H, I, J. Add 5 ml of propylene glycol solution containing raspberry ketone 1 (g) to an E beaker, dilute with 20 ml of distilled water, and vortex well to separate the solution. The top layer is raspberry ketone. After the F beaker is used as above, add 10 ml of the colloidal dispersion containing microorganisms; add 5 ml of propylene glycol solution containing vanillin 1 (g) to the G beaker, dilute with 20 ml of distilled water, shake well, and layer the solution. The upper layer is Vanillin. After the H beaker was subjected to the above operation, 10 ml of a colloidal dispersion containing microorganisms was added. Two (g) each of raspberry ketone and vanillin were taken and put into 20 ml of anhydrous ethanol, respectively, and fully dissolved. The I-beaker was a solution containing raspberry ketone, and the J-beaker was a solution containing raspberry ketone.

Experimental method: Take 2cm×2cm×0.2cm plastic boxes and take 2 plastic boxes and put them into a beaker with a proper amount of benzene and carbon tetrachloride. Take the remaining plastic boxes 6 boxes, respectively E, F, G, H, I, J, with a filter paper to cover the mouth of the beaker to prevent volatilization, standing for 24 hours to observe the phenomenon.

2. Soil Burial Experiments In the soil burial experiment in this experiment, polystyrene soil boxes were embedded in 10 cm soil layers in the ground where the soil was dry and the plants grew well. The degradability was observed. In the first stage, only non-degradable plastics were embedded, and in the second stage, degradable plastics were added for comparison. The test materials embedded in the soil were square, 4cm × 4cm × 0.2cm in size, dried at 60°C for 1 hour, weighed and recorded one by one, one tablet was taken every 7 days, washed, dried, weighed, and the weight was recorded. Happening.

3. Activated sludge landfill The active sludge in this experiment was taken as the microbiological provenance of the sewage sludge from Tianshan Sewage Plant. After the collection, aeration was carried out for two to three days. Each 12-hour rotation was allowed to stand and the supernatant liquid was discarded. Polystyrene was buried. Ethylene lunch box to observe its biodegradability. The test material for the activated sludge landfill test is rectangular, 12cm×6cm×0.2cm in size, dried at 60°C for 1 hour, weighed and recorded one by one, and taken out every 7 days, washed, dried and weighed. Record weightlessness.

four. experiment procedure;

Chemical dissolution:
Take 2cm×2cm×1cm foam plastics and put them into test tubes containing appropriate amounts of benzene and carbon tetrachloride, respectively. It can be found that the foam is completely dissolved in the solvent and a small amount of bubbles are generated. The solution in the test tube is viscous.

Solvent dissolution time phenomenon
E F G H I insoluble

J is insoluble
The viscous oily liquid produced on the surface of the beakers of E, F, G, H drops in absolute ethanol, resulting in white flakes or filiform confinements.

The use of chemical methods to degrade disposable lunch boxes, although short in duration and effective, will produce many unknown by-products that will affect the environment.