American researchers have developed a new method for capturing CO2 with its subsequent transformation into metal oxalates, which can be used as precursors for cement production.
It is noted that a chemist from the University of Michigan Charles McCrory and the research team he leads, together with the laboratory Jesus Velazquez at the University of California and Anastasia Aleksandrova’s lab at the University of California, Los Angeles, sought to transform CO2 for valuable material, while making cement production cheaper and more environmentally friendly.
«This research shows how we can take carbon dioxide, which is a waste product with zero or little value, and recycle it into something valuable. We’re not just taking carbon dioxide and burying it; we’re taking it from different point sources and reusing it for something useful», — Charles McCrory emphasizes.
In particular, the most common types of cement are portlandcement, which is made from limestone and calcium silicates. Its production is associated with relatively high energy consumption and significant carbon footprint. The researchers note that one of the types of materials that can be used as an alternative cement precursor is metal oxalates, simple salts.
The scientists add that lead can be used as a catalyst to facilitate chemical reactions to convert CO2 for metal oxalates. However, this requires a large amount of lead catalysts, which is dangerous for the environment and human health.
Scientists used polymers to monitor the chemical environment immediately surrounding lead catalysts. They managed to reduce the required amount of lead to one part per billion. The researchers showed that by controlling the microenvironment surrounding the lead catalyst in the chemical reaction that converts carbon dioxide to oxalates, they could significantly reduce the amount of lead required for the process.
In order to get oxalates, scientists use a set of electrodes. On one of them, CO2 is converted to oxalate. The other metal electrode is oxidized and releases metal ions, which bind to the oxalate ions and precipitate it from the solution as solid metal oxalate.
A team of researchers led by Jesus Velasquez hypothesized that lead in trace amounts could be used to control oxalate synthesis reactions. McCrory claims that once carbon dioxide is converted to solid metal oxalate, it will not re-enter the atmosphere under normal conditions.
The researchers are working on electrolysis to produce carbon dioxide on a large scale. The next steps will be to further study how to scale up the part of the process that produces the solid product.
The results of the study were published in the journal Advanced Energy Materials
Source: TechXplore
Spelling error report
The following text will be sent to our editors: