Extraction method and extraction equipment for farmland soil microplastics

Abstract

The invention discloses an extraction method for farmland soil microplastics, which comprises the following steps: adding a flotation solution into a pretreated soil sample, uniformly stirring, and standing to obtain a precipitation layer and a non-precipitation layer which are distributed in a layered manner; attaching the surface of the metal container attached with the oil film to the surface of the non-precipitation layer for at least 10 seconds, and then taking out the metal container; or, the extracting solution layer within 1 cm below the liquid level of the non-precipitation layer flows through the surface of the metal container to which the oil film is attached for later use; leaching the oil film of the metal container with ethanol for at least two times, and collecting leacheate; and after ethanol in the leacheate is volatilized, identifying to obtain the farmland soil micro-plastic. The micro-plastic in the farmland soil can be simply, quickly, efficiently and accurately extracted, and the micro-plastic can be conveniently observed and identified by using a microscope and an infrared spectrum. The invention further discloses extraction equipment for the farmland soil micro-plastic, human intervention is reduced, and the effective extraction equipment is provided for simply, quickly, efficiently and accurately extracting the micro-plastic in the farmland soil.

Description

technical field [0001] The invention relates to the technical field of extracting microplastics, in particular to a method and equipment for extracting microplastics from farmland soil. Background technique [0002] Over the past few decades, plastic waste has been accumulating in the earth's environment and has become an environmental issue of global concern. Although traditionally seen as a macro problem (i.e. large pieces of plastic), the problem of plastic pollution is also evident on a smaller scale. The concept of "Microplastics" was first proposed in 2004. It mainly refers to plastic particles with a particle size of less than 5mm. Microplastics come from a wide range of sources and are easy to migrate with the soil. Large specific surface area; relatively stable properties, can exist in the environment for a long time, and is difficult to degrade. Since this concept was proposed, the pollution of these small polymers to marine organisms has been an important resear...

AI Technical Summary

Problems solved by technology

The existing microplastics extraction methods mainly have the following disadvantages: (1) the saturated flotation liquid may have the problem of crystal precipitation, which is easy to interfere with the screening of microplastics; (2) the material filtered by the filter membrane may adhere to the filter membrane In fact, during the filtration process, the number of transfers of microplastics is increased, which can easily lead to the reduction of microplastics and interfere with the final determination of the abundance and type of microplastics in a certain quality.

Not conducive to a true and accurate assessment of the health risks of microplastics

[0004] Therefore, when studying the accumulation of toxic substances such as heavy metals, persistent organic pollutants, and antibiotics in farmland soil and the health risk assessment of microplastics, the existing methods have a great influence on the properties of microplastics themselves.

Microplastics cannot be efficiently separated from soil, and a fast and convenient method and equipment are urgently needed to extract microplastics from soil

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