I Have Just Registered And Am Very Interested, And Would Like To Know Where I Can Get koh, Is It Available At Supermarkets, Or A brand Name.
I Am In The Eastern Suburbs.
Would Be Trying To Make 1 Or 2 Litres At First Then Begin To Increase This To Finally Being Able To Make 60Litres Per Week.

In The Post Above I Ask Where To Get koh, I Have Since Discovered It Is Just Caustic Soda Flakes, But Please Correct Me If Iam Wrong.
And The Only Differance Between Naoh And koh Is The Amount Used.

Hi Dodge ,
NaoH is sodium hydroxide or "just caustic flakes" and also comes in a granular form looking like salt.. KoH or Potassium Hydroxide also comes in flakes.
If you use any old Caustic soda it could have all sorts of additives or impurities added.
Dont follow the america way and use "caustic soda", just because you can get it as draino at a super market.
We at the melbourne biodiesel club who are tried and tested at making biodiesel would recommend only use pure KoH. I do not have the contact of which chemical supplier we use at hand at the moment but can find out.
If you want a quality guaranteed chemical reaction to make biodiesel you must titrate the FFA's in your oil and use KoH only in the formulae
{(T + 3.5) x 3 } x V = K
T= titration value with NaoH standard solution.
V= Volume of oil to be reacted in litres.
K= weight in grams of KoH.
good luck.

When using NaoH the formulae is (T+3.5) x V = Na
where Na is the weight in grams of NaoH.

Just dont use NaoH.

Join the Melbourne Biodiesel club.
In the future we would also like to test a "standard solution" of KoH for titration. Although we have learned from industry standards NaoH is the "Standard solution" for titration. However KoH is the preferred alkaline for biodiesel reaction as it goes into methoxide solution easier, and always creates a better result.
And the grey water from water wash can be used as a fertilizer.
Cheers,, Darren.

Hi Darren,

I agree with everything you have said here for all of the reasons you have listed. However you have lost me with the equation you have written.


Why are you using a NaOH standard solution to titrate and then converting this amount to KOH. I think showing new users how to convert serves no purpose as there is no need to convert. You titrate with one or the other and you will be using the same, thus no need for conversion.

Just for the record - I am using 7 grams of KOH as a base and most oil I'm collecting is between 1-3grams titration.

Cheers
Joe

Yep Joe,
your right about why bother with the conversion,, just titrate with the right standard solution.
For the last nine months we have been using the same batch of standard solution and followed the old fashioned Chef's policy, "Dont **** with the recipe if it works well", But in the future we at the club will make a batch of standard solution in KoH. So Whats the formulae for KoH? is this Ticknels? = (T+ 9)x V = K
Cheers DAZ.
T= titration value.
V= WVO volume in litres.
K= KoH weight in grams.

9grams of KOH seems a little high for the base. I use 7 as the base and then titration.

Cheers
Joe

Ok So Koh Is The Way To Go, From What I Have Seen On The Net 7 Grams Was The Base.
Please Remember I have Not Evan Attempted To Make Any Yet, And I have Some More questions Before I begin.
Where Do I get The Dyes For The Titration.
Where Do I By The Methanol, Is It Sold In Smaller Than 20lt Drums, How Much Does Methanol Cost, Is There A Certain Brand That Is Preferred.
The Koh I Can Get From A Agriculture Chemical Supply Outlet.
And Thanks For Your Help.

You can the phenothaline red (I think its called) from a pool shop. Methanol - any brand and KOH should be 95% or better purity.
Joe

I am thinking of going to get a 44 gallon drum of Methanol in the next fortnight or so. I'm getting a few 25 litre fuel cans from a mate, so that I can decant it and not have one huge supply of methanol sitting around. If you want to go halves, let me know.

Cheers, your friendly RA.

Sorry Rasteve, But I Am Only After A Few Litres To Make My First Batch, That I Havent Had Time To Do Yet.