14 DAY TRIAL // Bio-oil is an ecological product and it will be cheap enough to compete with fossil oil in plastic manufacture, according to a team of scientists from the University of Massachusetts-Amherst, and featuring visiting scientists from Southeast University in China and the University of Nottingham, UK.
Today, pyrolysis oil obtained from biomass is basically used for electricity production and heating, but the team of scientists also proved that it could be converted into feedstock chemicals for manufacturing plastics, and at a far lower price.
George Huber, leader of the Massachusetts team, explained that “there are mainly six major petrochemicals that provide the whole plastics industry with its feedstock.
“We've worked out a way to make the same chemicals from biomass that you make from crude oil today, and we think we can be competitive with $60 per barrel oil using this technology.”
When the statement was taken, the price of the crude oil barrel was around $80, so spending $20 less and being eco-friendly is worth the shot.
Previously, scientists have used zeolite catalysts to make feedstock materials from pyrolysis oil, like aromatic and olefinic hydrocarbons, but the problem was that the yields were quite low.
The innovation brought up by the Massachusetts team was the addition of a hydrogenation step before the zeolite conversion, rising the quantity of the produced chemicals by three.
The procedure uses ruthenium and platinum for the hydrogenation, and then a commercial zeolite catalyst to convert the hydrogenated pyrolysis oil to the target molecules, which are all standard catalysts.
By joining these procedures, the scientists only need a partial hydrogenation, which makes high temperature hydrogenation and catalyst coking, unnecessary.
A fluidized bed reactor that recycles all coked zeolite catalyst, can be used for the zeolite step at the end, and scientists can even adjust the conditions to obtain different products, according to the demands.
The only thing that could limit this technology, according to Huber, could be the price of hydrogen, RSC reports.
Chris Saffron, an expert in converting biomass into fuels and chemicals at Michigan State University, adds that cost will not be the only limiting factor, and explains that pyrolysis oil is made in rural communities, and it will need hydrogenation before transport, due to its reactivity.
Huber suggests that splitting water using renewable energy sources could be a viable solution, or the necessary hydrogen could be acquired from more biomass.
“The fact that one can convert biomass to hydrocarbon fuels that could drop into existing infrastructure, is encouraging,” Saffron adds.
Huber adds that “there are several improvements we need to make, from designing better catalysts to designing more efficient reactors and improving process innovation,” but he adds that the paper is like “a roadmap of what needs to happen”.