Catalyst which converts bio-diesel waste into chemicals

In a finding that can have positive implications for the industrial catalysts industry, scientists have found a catalyst that can convert bio-diesel waste into useful chemicals.

Rice University chemical engineer Michael Wong, who has spent a decade amassing evidence that palladium-gold nanoparticles are excellent catalysts for cleaning polluted water, found that these particles could convert bio-diesel waste into valuable chemicals.

His study examined whether palladium-gold nanocatalysts could convert glycerol, a waste by-product of bio-diesel production, into high value chemicals.

In scientific parlance, the data from the study produced a "volcano plot", a graph with a sharp spike that depicts a "Goldilocks effect", a "just right" balance of palladium and gold that is about 10 times faster at converting glycerol than catalysts of either metal alone.

In chemistry, the role of the catalyst is much like that of a matchmaker. Catalysts cause other compounds to react with one another, often by bringing them into close proximity, but the catalysts themselves don't take part in the reaction.

Wong and colleagues have shown that covering 60-80 percent of the gold's surface area with palladium typically produces the ideal catalyst - though the exact percentage varies for different reactions.

"We found that the gold in our catalysts helps stabilise the palladium and prevents it from degrading. The catalysts in our tests had extremely high durability.

"Our best catalyst produced a glycerol product with higher purity and in less time than anything else we found in the literature," Wong explained.

The study will appear in a forthcoming issue of the journal Chemical Science.