Super porous material increases efficiency for carbon capture

Carbon capture and storage is a method that catches carbon emissions from the air to store it underground in geological rock formations. CCS is important in the mitigation of CO₂ emissions produced from the use of fossil fuels in electricity generation and industrial processes because even though the Earth naturally removes some of those emissions, humans produce it at larger rates than the Earth can handle.

A team of Australian researchers from Monash University and the CSIRO has achieved a new efficiency record for CCS using a super porous crystalline compound of metal ions filled with tiny magnets. The researchers designed the absorbent material called M-74 CPT@PTMSP that can capture CO₂ from several sources including directly from the air. The new material has delivered a record low energy cost of 1.29 MJ kg^-1_CO2, about 45% below commercially deployed materials.

The new material used is a type of metal organic frameworks (MOFs), crystalline porous absorbents with exceptional capacity to store guest molecules. For MOFs to be used in CCS applications, it is essential that the materials can be easily fabricated with good stability and performance since they tend to be unstable in wet conditions; thus, additional coating is needed to induce hydrophobicity to allow handling in ambient conditions.

The results from the research team signify a breakthrough for CCS technology and could fast track the adoption of MOFs for energy-efficient capture.

However, as I wrote in my previous post, CCS is a mitigation strategy and many scientists warn that the technology will not be enough to offset climate change effects.

The pandemic and CO₂ emissions

While the COVID-19 pandemic and worldwide lockdowns have resulted in a drastic decrease of CO₂ emissions in just a few months, the emissions are already rising again as countries resume their normal activities. Emissions are projected to rebound at 5% in 2021 and return to trend thereafter through 2023.

Because of the lockdowns, we have also seen a contraction in the economy during this time which translated into a reduction in energy-related activities which account for nearly 90% of global CO₂ emissions. Those activities include industrial, commercial, aviation and others; but those industries are also acutely impacted by the pandemic and their recovery is going to be gradual. Although the pandemic and its effect on CO₂ emissions is expected to delay projected emission levels, emissions keep rising.

The economic recession does not look like it is going to accelerate the energy transition either. On the contrary, environmental standards in the US and other countries have been lowered with the intention to accelerate the economic rebound. The government’s decision was made with total disregard of the effects this will have on climate change and pollution; and consequently, how detrimental it is to human health. Therefore, carbon mitigation technologies like CCS will continue to be relevant as carbon emissions increase.

Sources:

M.M Sadiq et al. Engineered Porous Nanocomposites That Deliver Remarkably Low Carbon Capture Energy Costs (2020), Institution of Mechanical Engineers, IHS Markit

Featured image: Photo by Marcin Jozwiak on Unsplash