Ferrihydrite coating reduces microplastic induced soil water repellency


Loading...

Date

2023-06-01

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

Addition of microplastics (MP) to soil has the potential to increase soil water repellency. However, coating of MP with soil abundant substances e.g., iron compounds, can reduce this effect. Here, we tested if pre-coating or in situ coating of MP with ferrihydrite (Fh) reduces soil water repellency. We applied hotspots of pristine and coated MP (20-75 mu m, PS and PET) to sand and imaged capillary rise via neutron radiography. Capillary rise experiments in wetting-drying cycles were conducted using water and Fh suspension. Pristine MP hotspots were not wettable. Capillary rise of water into coated MP hotspots differed in wettability depending on polymer type. While coated PS was still non-wettable, water imbibed into the coated PET hotspot. Capillary rise of Fh suspensions in wetting and drying cycles also showed varying results depending on polymer type. MP hotspots were still non-wettable and local water content increased only marginally. Our results indicate that Fh coating of MP changes MP surface wettability depending on polymer type and therefore counteracts the hydrophobic properties of pristine MP. However, MP coating is likely to be slowed down by the initial hydrophobicity of pristine MP. Dynamics of MP coating and increasing wettability are key factors for biotic and abiotic degradation processes.

Publication status

published

Editor

Book title

Volume

25 (6)

Pages / Article No.

1094 - 1101

Publisher

Royal Society of Chemistry

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Organisational unit

09732 - Carminati, Andrea / Carminati, Andrea check_circle

Notes

Funding

Related publications and datasets