Method for purifying recycled polyethylene

Abstract

The present invention provides a method for purifying recycled polyethylene. The method comprises obtaining recycled polyethylene; contacting it with a first fluid solvent to produce extracted recycled polyethylene; then dissolving the extracted recycled polyethylene in the solvent to produce a second fluid comprising polyethylene and suspended contaminants. a solution. The first solution was allowed to settle to produce a second solution comprising polyethylene and remaining contaminants. The second solution is purified by contacting the second solution with a solid medium to produce a third solution comprising more pure polyethylene. Finally, more pure polyethylene is isolated from the third solution.

Description

technical field [0001] The present invention generally relates to methods for purifying contaminated polymers through the use of pressurized solvents and solid media. More specifically, the present invention relates to methods for purifying recycled polymers, such as post-consumer and post-industrial recycled plastics, to produce colorless or clear, odorless virgin polymers. This method is particularly useful for polyethylene purification. Background technique [0002] Polymers, especially synthetic plastics, are ubiquitous in everyday life due to their relatively low production costs and well-balanced material properties. Synthetic plastics are used in a wide variety of applications such as packaging, automotive components, medical devices, and consumer products. To meet the high demands of these applications, tens of billions of pounds of synthetic plastics are produced globally each year. The vast majority of synthetic plastics are produced from increasingly scarce fos...

AI Technical Summary

Problems solved by technology

In previous methods, co-dissolution of other polymers and thus cross-contamination often occurred

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