Kerstin Hockmann

I am an environmental geochemist at University of Bayreuth and passionate about exploring the biogeochemical cycling of iron and sulfur in our human-impacted environment.

+++ News: MSc position offered +++ 

Research interests

 

My research interests lie at the interface of soil mineralogy and environmental geochemistry. I use an integrated approach that investigates the mutual controls between mineralogical transformations and (trace) element mobility in systems affected by anthropogenic activities. 

Specifically, my research explores how changes in redox status and associated iron and sulfur cycling impact the behaviour of contaminants and nutrients in our environment.  I also try to understand how anthropogenic elements themselves control secondary iron and sulfur mineral transformations – an important, but often neglected perspective in contaminant research. 

Methodologically, I use field and laboratory experiments and combine them with advanced analytical tools including spectroscopic and microscopic methods to obtain a mechanistic description of soil chemical processes. My research thus provides a fundamental framework for the design of novel remediation approaches to protect our ground and surface water from contamination. 

Current projects

Interplay between iron and antimony geochemistry

Antimony is a highly toxic environmental contaminant that is of growing concern. Over recent decades, dramatic increases in the production of Sb, due largely to its importance as a flame-retardant in electronics and plastics, has led to many cases of Sb release into the environment. In natural systems, the mobility of Sb is strongly affected by coprecipitation and adsorption interactions with Fe(III) oxide minerals. As such, the mineralogical transformation of Fe(III) oxides play a major role in determining the environmental fate and mobility of Sb. This project therfore investigates the impact of iron oxide (trans)fromations on the speciation and mobility of antimony.

Schwertmannite  -  a novel sorbent for phosphate removal

Phosphate is a key nutrient in eutrophication and many efforts are undertaken to reduce its input into surface waters.  An iron-based adsorbent that may be an ideal candidate to remove phosphate from water is schwertmannite, a by-product from acid mine drainage treatment. In this project, we investigate the factors and kinetics controlling short-term phosphate incorporation into schwertmannite and the concomitant formation of secondary Fe phases such as microcrystalline Fe(III) oxides.

Release of antimony from synthetic clothes

This seemingly "exotic" project (at least in the context of my research) focuses on the potential for children clothes woven from synthetic fibers to release antimony. Antimony may be present in synthetic clothing fibers because it is used as a catalyst during their manufacture. In order to study exposure and potential negative health effects while children are using the garments, we determined total Sb concentrations in a range of clothing samples, and subjected the fabrics to extraction by artificial sweat and saliva.

Want to know more? 

Do you have a question or are you keen to find out more about my work? Are you interested in getting involved into my research or do you want to write your MSc or BSc project as part of one of my research projects? I'd love to hear from you and I'll always be happy to help.