"Shall I put on my white lab coat for you?"

"Yes!", oh, er, I mean yes please, if you wouldn't mind Sir!

That was a brief exchange between me and Professor David Mullin in his tiny two-room laboratory at Tulane University in New Orleans.

As a TV guy I'm slightly embarrassed to admit to you that when your guest is a scientist and he's offering to put on a white coat for an on-camera interview - well - let's just say - that's a gift from God - it really is. We're all about images in TV you see - very important.

David had agreed to talk to me about a new vehicle biofuel he's producing from old newspapers and plant waste that gives motorists the same mileage as petrol but pumps far fewer pollutants into the atmosphere.

The fuel is called Butanol - a four-carbon alcohol, in contrast to ethanol, which is a two-carbon alcohol.

DAVID - "Ho daddy! It's Butanol, it smells like Butanol"

ME - "It's not bad"

DAVID - "Yeah, I mean you know, I wouldn't drink it"

Big industry makes Butanol from other chemicals for use in the paint industry but David's raw materials are recycled newspapers and agricultural plant waste that contains cellulose - the thing that makes plants stand up!  David told me more.

"The hard part of plants, it's a structural feature of plants, all plants from the smallest plants to the largest plants have cellulose as one of their structural features."

What David has come up with is a secret formula for producing the Butanol.

In laymen's terms: when the plant waste and newspapers are mashed into a grey broth - bacteria's added - 90 hours pass by - and Butanol's ready to be distilled out of the sludge that's left behind. (Plant waste is more crucial than newspapers by the way, that source will dry up one day of course, as the digital advance continues.)

David says, if you drain your tank of petrol, the clear Butanol liquid can go into a Ford, Fiat or Ferrari (please add your vehicle here - it doesn't have to begin with an F) right away without the need to modify their engines and without damaging them.

He says road tests prove Butanol returns the same kilometres per litre as petrol ... but with much less pollution.

There's just one problem, David explained.

"The development of technologies for scaling up this process so that you could produce billions of gallons, instead of just millions of gallons, produce billions of gallons."

In other words, how to produce enough Butanol to supply the global chemical industry plus enough to drive the world's engines?

David tells me several US corporations - with a wary eye on what happens when oil eventually runs out - are expressing interest in his work and that's what keeps him going. 

"I feel that this is a very important project, I hope to be able to help people - when this technology is fully developed to the point where I can drive down to the gas station and load - ha ha - my car up with Butanol ... for two dollars a gallon maybe"

David laughs ... but underneath he's really serious about this ... and as far as this correspondent can tell he's at the tipping point of actually doing something really big for mankind.