The climate crisis is arguably the biggest crisis mankind has ever faced. Except for the necessity to cut our CO2 emissions drastically and quickly, climate science also teaches us that we will need to remove already emitted CO2 from the atmosphere. One possible approach to achieve this goal is to react the CO2 from the atmosphere with certain minerals to form stable compounds. A particularly interesting candidate is olivine, an Earth abundant MgSiO4 mineral, that can react in contact with water and CO2 to MgCO3, a very stable mineral that can fix CO2 basically forever. However, natural ‘weathering’ of olivine is a very slow process and takes hundreds to thousands of years for olivine pebbles of a few mm in diameter. The reason for the slowness of this process is related primarily to the formation of passivation layers, which is rather poorly understood . To overcome this problem, in the first place, a better understanding of the microscopic processes governing the formation of these layers is required. To this end, we are setting up a new research line to investigate the conversion of olivine to stable carbon-rich compounds. As a part of this process, your role in the Masters Project is to setup a characterization platform based in microfluidics in combination confocal Raman microscopy with the ultimate goal to follow the conversion of olivine in situ.
An olivine pebble and its Raman spectrum accompanied by a 2D Raman intensity map.
The specific goal of this Master assignment is to contribute to the development of this setup and to the establishment and validation of the required measurement technologies. You will set up a simple microfluidic chip that allows to pass aqueous fluids and CO2 at variable temperature and pressure (e.g. up to 100°C; 50bar) and you will perform confocal Raman spectroscopy measurements to determined the CO2 content and local pH of the fluid based on the Raman spectroscopy measurements. The goal is that we will be able to follow the evolution of the fluid composition during the conversion (‘enhanced weathering’) reaction of olivine inside the chip. Depending on your interests, you can become more involved in the fluidics and materials screening part and/or in the confocal Raman microscopy and data analysis part.
In addition to the standard learning objectives for a master’s project (research planning, academic writing, data presenting, how to work in a lab environment, etc.), you will:
· Learn how to setup up a microfluidics platform for materials research under high pressure and temperature conditions
· Learn about high resolution Raman spectroscopy measurement and data analysis
· Learn about aqueous electrolyte and their properties (which are ubiquitous in nature and technology)
· Have basic chemical-lab training (preparing solutions and surfaces, etc.)
· Depending on your interest, you may write analysis code in Python or Matlab
· Daily Supervision: Vincenzo Alagia (email@example.com)
· Supervision: Prof. Dr. Frieder Mugele (firstname.lastname@example.org)
: E.H. Oelkers et al., Chemical Geology 2018 (recent review on olivine)
: S. Nair et al., National Science Review 2020 (an illustration of PCF Raman methodology)
: T. Geisler et al., Nature Materials 2019 (high resolution Raman for in situ glass corrosion)