Much of what society depends on in the modern day has its roots in fossil fuels, including electricity, transport, heating, and plastic production. However, fossil fuels are a finite resource with coal, gas and oil projected to reach depletion within 42 years' time (New York Circular City Initiative, https://www.circularnyc.org/). In addition to fuels, we mine and consume a large amount of metals and minerals, which are also non-renewable resources. This may seem a less urgent situation until we realise that our smartphones are laden with rare earth metals, many of which are running out.
What if we could recover metals from waste we produce, waste which would otherwise have been put into landfill, and, furthermore, transform it into something useful? This will form part of my project to develop circular economy approaches, addressing the problem of our current and mostly linear economy. I will be transforming struvite, a problematic waste mineral produced as a consequence of waste-water treatment (WWT), into industrially useful layered double hydroxide (LDH) materials. The magnesium within the struvite will be a metal precursor for the LDH synthesis. I will aim to synthesise these using green chemistry principles and utilising various sources of waste throughout.
LDH's have potential applications in many different fields. Here, I will focus on their role as catalysts in reactions such as biofuel and green hydrogen production, as well as carbon capture and transformation. Furthermore, I will try and design the synthesis and use of the LDH with Northumbrian Water Groups' WWT plant in mind, creating a circular economy approach in which the waste they produce has been transformed to something they can once again use. This will help the company attain its net zero waste target.
A novel approach to LDH synthesis is being taken in this project, alongside the use of the LDH to create renewable resources and circular economy pathways.