Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Civil and Environmental Engineering

First Advisor

Suzette Burckhard


Adsorption, Desorption, Lead, Microplastics, Visual Minteq, Wastewater


Microplastics are an emerging concern due to their harmful effect to organisms and their ability to facilitate transport of contaminants including heavy metals. Microplastics can enter the environment through wastewater treatment plants, landfill leachate, and littering. Once in the environment microplastics can be distributed throughout rivers, the ocean, and lakes. In order to understand the adsorption of heavy metals to microplastics a geochemical modeling study was completed using Visual Minteq. Lab tests were completed to better understand what constituents are available in wastewater at four different locations: influent, clarifiers, digesters, and effluent. These constituents were then used to observe how adsorption of lead to plastic was affected under different conditions. The conditions that were tested were: without any additions, with DOC present, with DOC and lead present, with DOC, lead, and a plastic adsorption surface present, with lead and a plastic adsorption surface present, with lead, and a pH sweep. It was concluded that lead can be affected by both DOC and a plastic adsorption surface but the adsorption to plastic is not affected by DOC. Additionally, it was discovered the pH does not affect adsorption of lead to a plastic surface, but instead more species occur at a high pH reducing lead’s concentration.

Library of Congress Subject Headings

Microplastics -- Environmental aspects.
Heavy metals -- Absorption and adsorption.
Sewage -- Purification -- Adsorption.
Sewage disposal plants.
Water -- Pollution.

Number of Pages



South Dakota State University



Rights Statement

In Copyright