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Biodiesel => Chemistry and process => Topic started by: db on January 06, 2013, 08:10:55 PM

Title: Is there a way to test Koh? I think it may be 'off'
Post by: db on January 06, 2013, 08:10:55 PM: I'm using some Koh flakes that I've had hanging about for around 18/24 months.

Is there a way of testing to see if it's 'gone off' as I'm using loads?

Dawson
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: 1958steveflying on January 06, 2013, 08:28:20 PM: My personal experience is when caustic goes off it starts to clump together as it is taking on water, if it has been in a perfectly sealed container it ought to be fine.
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: db on January 06, 2013, 08:41:43 PM: I must admit it looks ok.

I suppose all I need to do is convert 1L brand new oil with 7grammes Koh and see If I get full conversion.
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: Tony on January 06, 2013, 09:13:12 PM: Got any NaOH (or fresh sealed 500g drain cleaner?) Could titrate with both and compare?
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: Carrington on January 06, 2013, 09:39:22 PM: The easy way is to mix 1g with a litre of water and check the ph
I cant work the calc's so maybe someone could do a sample with some known KOH and report back or I can maybe do it sometime tomorrow

Paul
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: 1958steveflying on January 07, 2013, 06:28:27 PM: Quote from: db on January 06, 2013, 08:41:43 PM
I must admit it looks ok.

I suppose all I need to do is convert 1L brand new oil with 7grammes Koh and see If I get full conversion.

If you can be certain your Methanol is okay.
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: db on January 08, 2013, 09:23:46 PM: Quote from: Carrington on January 06, 2013, 09:39:22 PM
The easy way is to mix 1g with a litre of water and check the ph
I cant work the calc's so maybe someone could do a sample with some known KOH and report back or I can maybe do it sometime tomorrow

Paul

Hi Paul, I'm not sure how to check to ph?
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: db on January 08, 2013, 09:25:28 PM: Quote from: Tony on January 06, 2013, 09:13:12 PM
Got any NaOH (or fresh sealed 500g drain cleaner?) Could titrate with both and compare?

I've non left I'm afraid.
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: Ats on January 08, 2013, 11:27:40 PM: Normally is it goes off. The first thing that happens, is that it will absorb water and become a liquid.

The other way would be that it can absorb CO2, then it will become potassium carbonate.

It will absorb water first and if it is still flakes, and has been sealed, then I would say it is still usable.
Title: Re: Is there a way to test Koh? I think it may be 'off'
Post by: db on January 11, 2013, 09:37:41 PM: I reckon it's ok as it's still flakes. Also done another batch yesterday and only used 1/2 the amount this time.

Dawson