Biocide?

[dkwflight]

Hi group

What if any biocides do you use to keep things from growing in your stocks of WVO?
Dennis.

[Tom]

I've got the Pri-D biocide, but I have not used it in wvo yet. Also I got a question yesterday will wvo go "bad" if just left to sit?

[solarguy]

WVO will go "bad" or "worse".  It can become (or get more so) rancid.  This smells a lot like really frangrant dog vomit and is a real treat to make fuel of any kind from.

Also, the fatty acid content of used oil will go higher, which makes the straight stuff worse for your injection system, and makes conversion to biodiesel less efficient and  a big pain in the  a$$.

Both of these effects are worse/faster if the oil has much water contamination, has lots of access to 02,  and at warmer versus cooler storage temps.

Filtered, dried, cool stored wvo in full containers with little/no air might last a considerable time, measured in years.  More with biocide, which I am slowly reading up on.

Good luck and have fun!

troy

[Halfnuts]

What you're talking about is rancidity.  There are two types with different causes, one called hydrolytic rancidity is caused by the growth of microbes that are busy eating the oil and producing volatile organic acids as waste products.  Butyric acid is the "dog vomit" smell most likely.  The other mechanism is called oxidative rancidity, caused by exposure to oxygen in the air. 

Filter through a coalescing-tpe water separating oil filter to remove any water, or heat the oil to kill the bugs and use a biocide like Stabil, and you should be able to store the WVO for some time.  Keep a tight lid on the container and you'll control the oxidative rancidity.  BHA and BHT are used in foods to control oxidative rancidity and can be used for stabilizing fuel as well.  Transesterification via methoxide to produce biodiesel will get rid of the hydrolytic rancidity problem by removing water and the free fatty acids and glycerol components, as well as by making the oil too alkaline to support growth.  The residual alcohol should also keep anything from growing. 

Halfnuts

[dkwflight]

Hi I know most organic materials and some inorganics are basicly unstable in combination with air and water.
So.. the first step is to dry it!
Next is to keep oxygen from it!
Next maybe a UV light? They aren getting cheaper in th A/C industry, I know. A UV light may be the cheapest alternative to keep vegetable oils fresh or at least from spoiling.
Dennis

[Halfnuts]

Light too!  Don't forget light!  UV can be good for keeping bugs from growing in water, and can fry bacteria that cling to dry surfaces like A/C ducts, but I wouldn't automatically assume the same about veggie oils.  UV might not penetrate oil at all even though it appears transparent to our eyes which can't see UV.  Remember vegetable oils are natural materials and will break down on exposure to air, water and light much faster than mineral (Dino) oils will.  And some organic chemical reactions are enabled or accelerated by high energy light such as UV, so I would't try it until I had more informaiton. 

Get the water out of the oil until it is clear, filter it thoroughly, store it in air-tight containers, and then use it up quickly.  Again, veggie oil is natural, it's not a pure substance, but is composed of many oils and oil-soluble materials that were pressed out of the original feedstock.  As such there are all kinds of things in the environment that will degrade it back to where it came from, CO2 and H2O.  The clock starts ticking as soon as the oil is harvested.

Halfnuts

[SHIPCHIEF]

I read the label on Biobore JF.
Use gloves, face mask, protective clothing. Avoid exposure, do not reuse container, do not dispose of container in land fill, etc. etc. Heck, if you read between the lines it says: DO NOT USE THIS PRODUCT!!!!
I'm with Halfnuts here. Use natural processes like filtering, water removal, air tight storage and use it up quick.
Scott E