I also do reactions at ambient, and have achieved full conversion without the mix rising above 30C. Some initial warming up to around 25C is required to get the methoxide to mix into the oil.
I also use the enhanced glyc prewash, which on my last reaction, resulted in 8ml dropout in the 10/90 test.
I took a sample after 30 minuets and it slowly separated. Another after 1 hour and it separated a bit quicker. Then another when finished at 1 and a half hours, which separated quite quickly ( like normal). Using normal cement to dry the methanol appears to work well.
Just on the glyc prewash, can you mix it at room temp?
Yes, as i pointed out in my earlier post, As long as everything remains liquid temperature is not a limiting factor to the reaction, it just requires that you mix longer the cooler the reaction is.
So just to clarify your position here,
Are you saying that you perform a single stage reaction at room temperature that passes the 3/27 test in 45 minutes or are you just saying that you do your reaction at room temperature?
It is Common Knowledge that the reaction can be performed at room temperature.
Hmmm, I have never had problems mixing the methoxide with the oil at room temperature.
I have even performed tests where I put the oil and methoxide into a fridge and successfully performed the reaction at around 5C.
Yes, that is normal. If all you want is separation then that is all that is required.
However, if, as you said earlier that you are "going to try and make top grade bio to run in a common rail motor." then you will need to do a 3/27 test to check the conversion of the biodiesel.
You can not tell by looking at biodiesel whether it is very high conversion.
I have never used cement to dry my methoxide and it works just fine too.
Yes you can as long as everything remains liquid. Of course if you want to make high conversion biodiesel then it will require a longer mixing time if you perform the reaction at room temperature.
I'm rather new to this myself.
All I was saying was that I do my reaction at between 25 to 30C. I never try to get full conversion in a single stage, as I believe that draining the glyc after the first reaction and then doing subsequent small reactions (usually only one or two) is the most efficient way to proceed to minimise chemical usege.
I believe that you are in Australia? Wonderful country. My brother moved there when Vodafone were setting up their mobile network and he gained citizenship.
Having read this board for a while, I see that you run a very tolerant engine and that full conversion of your oil is not so critical. Here in Europe we have been forced to go down the common rail route, and I am always very careful to make sure that my fuel is fully converted (well, according to the 10/90 test anyway) as well as thoroughly de soaped - I water wash- and then dried. It's impossible to buy newer diesel cars that are not common rail now, so quality is critical.
As for mixing the methoxide with the oil, my experience is different to yours in that I have had problems around it not mixing, but just floating to the top and staying there. So I always warm the oil to around 25C.
As I say, I'm not an expert but just try to follow a simple procedure that works (most of the time).
Enjoy your sun down there Tilly! You don't want to know what the weather is like here in the UK.
No. It's wise to also test for at least water and soap.
This site will help you make better biodiesel:
Yes, performing the reaction using several stages will use less total chemicals providing everything else is equal.
The Trade off is that multistage reactions take longer to perform than a single stage procedure.
Yes, I bought a new 2006 Musso with the old idi mercedes 5 cylinder diesel- the "Gold Standard" of alternate fuel diesels.
These were the last idi diesel cars to be sold in Australia and 2006 was the last year they were sold here. All diesel engines sold in Australia after 2006 are now commom rail Direct injection engines
Indeed, it is very pleasant here 12 months out of the year. My wife is off to Europe next week with some friends but I will not be going.
12 hour flights travelling cattle car class and a cold winter at the end of it holds no appeal to me
You asked about doing the glycerol pre-treatment at ambient temperature. This doesn't work too well. As the reaction is what is known as an equilibrium reaction and even though there are excess chemicals in the glycerol, the reaction is too slow to proceed with any degree of practicality at ambient. The glycerol is also very slow to drop out.
I find it a bit of a waste of energy, heating up the oil with electric for the pre-wash to then do the reaction at ambient, so I use an immersion heater that runs on crude biodiesel for economy.
Tilly, I looked back through my notes re the process at ambient without treating the oil at all. I can't find them but from memory it was in the region of 8.6 gms KOH/litre + 20% methanol.
The single stage process with no pre-treatment does not suit my way of working. I have plenty of time and prefer to do a pre-treatment then two more stages.
A while ago I costed out the price per litre doing 1 stage, then multiple stages at ambient.
Single stage cost is over 10 pence/litre (mainly due to extra chemical costs)
Multi stage (even though more electric is reqd for the pump) is down to just over 7 pence/litre (much reduced chemicals, especially methanol)
This amounts to nearly £100 over the year.
This statement is in total disagreement with what you posted to terracan in this thread Dec 11 when you told him;
“...I mostly react at ambient temperature and leave each stage around 45 mins, it works very well."
Now, in this most recent post you say:
”You asked about doing the glycerol pre-treatment at ambient temperature. This doesn't work too well...the reaction is too slow to proceed with any degree of practicality at ambient...so I use an immersion heater that runs on crude biodiesel for economy “
So which is it, you do or you do not use heat to perform the reactions.
Read my post again Tilly, My process is exactly as I describe.
terracan, PM sent.
I have read your post again.
I now understand that while you originally claimed that you "mostly react at ambient temperature and leave each stage around 45 mins" , you actually " use an immersion heater that runs on crude biodiesel" to heat the first stage reaction.
Terracan, PM sent
I am still struggling with your claim here.
While I am not a chemist, I have been making biodiesel and studying biodiesel production for the best part of 15 years.
In that time I have talked to a number of chemists and read many reports and scientific papers that say and demonstrate that the warmer the reaction, the quicker it goes.
Over the years I have conducted several experiments that tested this very point. In each case I found that the temperature DID Affect the speed at which the reaction went.
In every case the warmer the temperature, the quicker the reaction went.
This is from wikipedia
"As a rule of thumb, reaction rates for many reactions double for every 10 degrees Celsius increase in temperature,"
At this point I will stick with what I have learned over the years and invite you to have a closer look at how raising the temperature of a reaction affects it's reaction rate.
I didn't say the temperature doesn't affect the reaction. What I said was it doesn't affect it as much as the rule of thumb suggests.
If I add enough chemicals for my first 'normal'reaction to achieve a dropout of 1.5mls (roughly 85% conversion) at an average of only 15degs C and I mix 45mins to get this then the rule of thumb is NOT correct.
It's an easy enough test for you to try yourself Tilly.
Actually, that is not what you said.
You should go back and read my post and your post contradicting what I had said.
I will also once again ask you to verify that when you did your single stage reactions (No neutralizations, enhancements, pre washes, etc) at room temperature, it actually passed the 3/27 test in just 45 minutes reaction time.
Most reports and papers I have read concerning room temperature single stage reactions usually nominate 4 to 8 hours to reach completion at room temperature, so I am finding it difficult to believe that you can pass the 3/27 test in a single stage reaction in 45 minutes at room temperature as your post implys.
"I mostly react at ambient temperature and leave each stage around 45 mins, it works very well."
I am guessing that you perform your first 'normal' reaction after performing one or more 'paranormal' reactions
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