EAST LANSING, Mich. (WLNS) — Close to 90% of U.S. plastic waste ends up in landfills, incinerators, or as pollution in the environment. Muhammad Rabnawaz, a Michigan State University professor recently inducted into the National Academy of Inventors, has shown how table salt could help.
“This is really exciting,” Rabnawaz said Thursday in an MSU news release. “We need simple, low-cost solutions to take on a big problem like plastics recycling.”
Rabnawaz describes his findings in a recent paper, “Revolutionizing Plastics Chemical Recycling with Table Salt.”
Pyrolysis is a process that breaks down plastics into a mix of simpler, carbon-based compounds, which manifest in the three forms of gas, liquid oil and solid wax.
Rabnawaz said the wax component is often undesirable, but can account for more than half of the products of current pyrolysis methods. Catalysts are helpful, but can often be toxic or too expensive to use in managing waste plastics. “No company in the world has that kind of cash to burn,” Rabnawaz said.
Rabnawaz and his team have now shown that table salt alone can eliminate the wax byproduct.
The major byproduct that the team produced while using table salt in pyrolysis was liquid oil that contains hydrocarbon molecules similar to what’s in diesel fuel.
Researchers also demonstrated how the salt catalyst is reusable. “You can recover salt by simply washing the obtained oil with water,” Rabnawaz said.
Based on a preliminary analysis, his team has estimated that a commercial pyrolysis reactor could triple its profits, just by adding salt–thereby, potentially solving the economic barrier to recycling more plastics.
It may go to show that, in the 21st century, even table salt could be revolutionary.
