Oh of course ... hehe
But again everyone should JUST heat the soup, as the
Naphtha will equilibrate nearly at the temperature of the soup upon combining, it takes nearly
no heat to get up to that temperature. Now you can do what you want, but why heat 2 soups separately, when you could just heat 1 and you will get the same results?
I will just calculate it here, those are the heat capacities:
0,19497 J/(mol·K) (25 °C) for Hexan
and
4,184 J/(kg·K) (14,5 °C) for water
Ok it changes with temperature and Naphtha is not just hexan so its not 100% accurate, but I guess you get the point:
Ok we have
1 L of water and we throw in
200 ml of Napthha.
First let's check how much heat we applied to the water to raise it to 60 °C:
delta Q = m * cp * delta T
= 1 kg * 4,184 kJ/kgK * 40 K =
167,4 kJand now how much heat is needed to get 200 ml Naphtha up to that temperature? Weight of Naphtha: 200 ml and it wieghs 660 g per Liter = 0,2*660 = 132 g and this is 1,53 mol.
delta Q = 1,53 mol * 0,19497 J/molK * 40 K
=
11,9 kJThis means the Naphtha will steal like 12 kJ out of 167,4 kJ from the water, leaving the water at ~ 57 °C. Therefore to be 100 %ly safe,
just heat the water to 63 °C and throw your Naphtha in, it should be 60 °C Of course all those stuff dissolved in the water would raise the needed heat a bit, but if so then don't heat it to 63 but to 65 or whatever, also simply trying it out instead of Math would make it clear.
long story short I just want to show everyone that
A:
heating Naphtha is a waste of time when you could just
add 3 more °C for your soup
B: heating Naphtha and
NOT HEATING the
soup is totally pointless, you will
end up at 20 °C in the end anyways, as if you did not heat anything at all.
Quote:- Seems like freeze/thaw during acid stage has the same effect on yield as heating the acid and base stage without freeze/thaw.
I dont completely understand the freeze - thaw, so this means that AFTER you did the acidic cook you froze and thawed the soup?
Normally I thought it was recommended to do this before the actual cooking step. Is there a benefit to do it with the soup? If I get it correctly you use it before basifying, but then you already dismissed the plant material and I thought the freeze-thaw is to break it upen prior to the acidic extraction step.
Also in that quote you say possibly it has the same effect.
But it may also be that (if I got it correctly and you did it AFTER you already dismissed the plant amterial) it has no effect. You have nearly the same yield like with the 60 °C base + 20 °C soup.
But 60 °C + 20 °C soup should be like 22 - 23 °C overall. So this would be nearly as no temperature increase at all. Therefore one may say that this is just 20 °C of both and NO freeze-thaw step.
And as the freeze-thaw test had the same result like this, it seems like the freeze-thaw did not make any difference.
So I understood that you did the freeze-thaw AFTER the initial cook, but maybe I got you wrong and you mean before.
And then this would be really interesting, as all people tell to do one before cooking and your test is basically:
Freeze-Thaw vs. no Freeze-Thaw
And it does not seem like the freezing did improve the yield at all.
I also wanted to do a test on this, but haven't done so far as it is just so easy to freeze-thaw as you do not need to do anything meanwhile. But I am also really curious is this REALLY improves anything or not. Because we should definetly check it out, as everyone tells it and everyone does it and probably it is not even needed?
I could only imagine if you just cook your stuff for 10 mins, then maybe it makes a difference, but who is only cooking for 10 mins ? Oô