Promising Plastic Manufacturing Process Could Save Earth Much

A brand new technology for manufacturing plastic is setting the horizon alight with its potential to dramatically reduce the costs and carbon emissions on this incendiary front.

Scientists at Exxon Mobil Corp. and the Georgia Institute of Technology have devised an alternative to the conventional way plastics are made that could potentially reduce the load dumped into the Earth's atmosphere by 45 million tons a year.

The breakthrough, published last week in the esteemed journal Science, has as its centrepiece a process that may help chemical plants shrink their carbon footprint and, in so doing, facilitate the world's goal to meet ambitious carbon-cutting targets.

This new process hinges on a carbon-based membrane that can separate molecules as small as a nanometre (a sheet of paper is 100,000 nanometres thick). The membrane acts as a filter to separate a chemical building block, para-xylene, from similarly sized hydrocarbon molecules.

The Exxon-Georgia Tech process, still in development, is 50 times more energy efficient than the current method—which uses high-energy heat, crystallization techniques that involve repeatedly freezing the molecules, or adsorption processes that require boiling and distilling hydrocarbon mixtures—to achieve the separation.

Molecular separation processes are essential to produce clean water, pharmaceuticals, chemicals, and fuels. The paper's authors say about 40% to 60% of the energy used in their production is spent on separation and purification processes.

"In effect, we'd be using a filter with microscopic holes to do what an enormous amount of heat and energy currently do in a chemical process similar to that found in oil refining," said Mike Kerby, corporate strategic research manager at Exxon Mobil, in a prepared statement.

The revised version could save US$2 billion annually and reduce carbon dioxide emissions by up to 45 million tons globally per year. That's the equivalent output of five million U.S. homes, Exxon said.

The worldwide shift to cleaner sources of electricity requires the exuberant participation of industrial manufacturers. After all, chemical plants account for about eight percent of current global energy demand. As more Third-World countries up their use of electronics and plastics, that fraction is projected to grow.