'Ultraselective' process creates p-xylene from biomass

Chemical engineering at the University of Massachusetts Amherst have developed a process for making p-xylene, an important ingredient of common plastics, at 90 percent yield from lignocellulosic biomass.

According to researchers Wei Fan, Paul Dauenhauer and colleagues, this is the highest yield achieved to date.

The biomass-derived p-xylene can be mixed with petroleum-based plastics

The chemical industry currently produces p-xylene from more expensive petroleum. Xylene chemicals are used to produce a plastic called PET.

The new process could make the same chemical from lower-cost, renewable biomass. It is described as “ultraselective” because of its ability to achieve 90 percent selectivity for the desired product.

“The biomass-derived p-xylene can be mixed with petroleum-based plastics, and consumers will not be able to tell the difference. But manufacturers and chemical companies will be able to operate more sustainably and at lower cost in the future because of this discovery,” said Dauenhauer.

The UMass Amherst team’s discovery reveals the impact of nano-structured catalyst design on renewable chemical processes.

Led by Fan, they examined a large number of nano-porous catalytic materials, including zeolites, investigating their capability for producing p-xylene. A specific material identified as ‘zeolite beta’ was found to be optimal.

“We discovered that the performance of the biomass reaction was strongly affected by the nanostructure of the catalyst, which we were able to engineer and achieve 90 percent yield,” Fan said.

This discovery is part of a larger effort by the campus’s Catalysis Center for Energy Innovation to create breakthrough technologies for producing biofuels and chemicals from lignocellulosic biomass.