The National Institute of Standards and Technology, Gaithersburg, MD has found out a way to reduce the energy demand in plastic manufacturing by using a class of materials that can filter impurities more efficiently than the conventional manufacturing process. The findings were published in the May 19th edition of the Science journal.
According to the research report, materials called metal-organic frameworks (MOFs) can effectively remove the contaminated acetylene from ethylene, the material from which most of the world’s plastics are made. It also suggested that filtering out acetylene with MOFs would produce ethylene at a higher purity according to the industry demands. This study will also sidestep the current need for converting acetylene to ethylene through an expensive catalytic process.
Polyethylene is plastic that is widely used in the manufacture of water bottles, grocery bags, and household appliances. It is a pliable material made by stringing together long chains of a simpler molecule called ethylene. Worldwide demand for plastic makes ethylene the most produced organic compound in the world. Every year more than 100 million tons of ethylene is manufactured.
However, the newly made ethylene is not pure enough to become plastic because the refinement process also creates a substantial amount of acetylene. This can ruin the catalysts that enable ethylene molecules to be strung together. The conventional industrial solution is to convert this undesirable acetylene into ethylene, as well, but this step requires the use of palladium, an expensive metal. It also consumes a significant amount of energy.