Tiny Biodiesel Reactors

Lee_in_KC writes "A professor of chemical engineering at Oregon State University developed a small reactor to directly convert vegetable oil to biodiesel. Goran Jovanovic reports his invention is approximately the size of a credit card. It pumps vegetable oil and alcohol through parallel channels to convert the oil into biodiesel almost instantly. Current mainstream methods to produce biodiesel take more than a day and also produces other byproducts which must be neutralized before disposal or use in other manufacturing processes."

Comments

better article

[Quixote]

You can find a much better article here.

I'm not sure how feasible this is. Also, as per the longer article (above), it does not eliminate the need for NaOH; unless I'm reading it wrong.

Re:better article

[NitsujTPU]

This is discussed in the article.

NaOH is the catalyst used in the reaction.

The microreactor under development by the university and the Oregon Nanoscience and Microtechnologies Institute eliminates the mixing, the standing time and maybe even the need for a catalyst.

Re:better article

[Hal_Porter]

You can run diesel engines on unrefined rapeseed oil if you tweak them a bit

http://en.wikipedia.org/wiki/Straight_vegetable_oi l
In the UK drivers using SVO have been prosecuted for failure to pay duty to Customs and Excise.

Biodiesel just means that you can run an umodified engine -

from
http://en.wikipedia.org/wiki/Biodiesel
Sometimes even unrefined vegetable oil is incorrectly called "biodiesel". Unlike unrefined vegetable oil, biodiesel does not require fuel pre-heating and filtration due to issues with coagulation, and also require no or minimal modification to the fuel system.

Re:better article

[Gordonjcp]

I've run a few cars on straight waste veg oil. You *do* have to pay fuel duty on it, but at a much lower rate than mineral diesel. You can run straight veg oil in pretty much all the PSA diesels (Peugeot / Renault / Citroën / some Volvo) if they have a Bosch fuel pump - the Lucas ones are more efficient but have tighter running clearances and the increased viscosity will damage them. I've had best results with the 2.5 turbodiesel as fitted to the Citroën CX and various trucks. The XUD-series engines work fairly well too.

In general running pure veg oil is a pain in the arse because it's very hard to get the engine started. If you weren't going to switch off for more than a few minutes it would be just fine (which might be practical for generators).

Re:Did I miss something, or..?

[Doytch]

Glycerin is not a problem in and of itself, it's the catalyst properties that are mixed in from the NaOH that end up creating useless glycerin that must be purified to be of use. Since this may eliminate the need for the catalyst, the glycerin can be used immediately without purification.

Cellular Reactions.

[Anonymous Coward]

"Essentially, the reactors, which can range in size from less than a square inch to several square inches, use tiny, parallel channels no larger in diameter than a human hair, to bring the alcohol and vegetable oil into contact with each other in the presence of a sodium hydroxide catalyst.

What results is not only a tiny stream of 100 percent biodiesel fuel, but also glycerin, the latter having uses in making soaps and even fossil fuel-free plastics.

The microreactors, each of which produces only a minute amount of biodiesel, are designed to be used with thousands of others of the same size in a single, integrated system."

Sounds like the mechanical equivalent of an organ.

Re:I'm waiting

[Cid Highwind]

There is a 100 mpg carburetor patent that an oil company is sitting on.

This story has been floating around since the 1950s, far longer than any patent term. Either EvilOilCo has a hundred-year patent to go with their hundren-mile-per-gallon car, or there never was such a device...

Re:Just what America needs...

[PapayaSF]

No, you're looking at it backwards: think of all the excess fat we have available for automobile fuel! Every liposuction could be like a little oil well....

What room temp IQ modded this troll?

[Flying pig]

This is a joke, and somebody who doesn't know organic chemistry from his ass thought it was a troll. Dear idiot, the sodium hydroxide combines with the added alcohol to form sodium methoxide, which then reacts with the oil. The NaOH is not in fact a catalyst, it is an intermediate reaction component. And yes, it is corrosive.

Don't they teach kids ANY organic chemistry nowadays? How are we to produce the next generation of recreational drug designers and home-made explosives producers that made the West what it is today?

Re:NaOH is a reactant not a catalyst

[0xC2]

You are half correct. The intended process is transesterification, which is direct (stepwise) substitution of the glycerol in fat with three molecules of alcohol (say for example ethanol). So one large triglyceride (a molecule of fat) is broken down to 3 fatty acid ethyl esters and one molecule of glycerin. This process is catalytic, and can be catalyzed by acid or base.

(BTW, oil = liquid fat).

The problematic side reaction is hydrolysis of the oil to fatty acids (i.e. saponification to soap), due to the presence of water in the crude oil. This side reaction is compounded by the difficulty of mixing the fat and alcohol during reaction (fat and alcohol not completely miscible), which reduces the efficiency of the catalytic transesterification, thereby increasing the extent of the unwanted side reaction (saponification to soap). Also crude oils contain fatty acids which could quickly neutralize a catalytic amount of sodium hydroxide (stopping the process).

Therefore the conventional (batchwise) process is to treat the fat with excess sodium hydroxide in a non-catalytic initial step; whatever water is present is consumed in a conventional, non-catalytic saponification to sodium salts of fatty acids, glycerin, and excess sodium hydroxide. Any fatty acid is converted to its sodium salt. All of which are easily removed from the fat (oil). The resulting purified fat is suitable for the catalytic transesterification process to biodiesel.

I'm a chemist, but haven't worked with these microreactors, so the following is guessing:

A microprocessor can increase the efficiency of the desired transesterification by allowing intimate mixing of the alcohol and the fat, which is half the battle in this case. Also, a continuous processor can have advantages over batch processing in that the reaction conditions (pH, temp, etc.) can be dynamically controlled.

My guess is that the fat (oil) would still require pre-treatment to remove water, fatty acids, and fine particles before entering the fuel cell.