Questions running a reflux still

Other discussions for folks new to the wonderful craft of home distilling.

Moderator: Site Moderator

Post Reply
charcoal
Swill Maker
Posts: 262
Joined: Sat Nov 02, 2019 3:28 pm

Questions running a reflux still

Post by charcoal »

My process:

I heated the boiler with 8 litres of 30% ABV wash until vapour temp after dephlagmator crossed 50C. Then I started cooling the condenser and dephlagmator. I left it running for full reflux for 40 mins or so and then then I reduced cooling slowly until some drops started to appear.
I saw the first drops appear at 71.8, then at 77.1 and then at 78.4. The number can be few places off because of maybe a not-so-accurate thermometer. I have highlighted them in the table
I found these numbers in the table at viewtopic.php?t=72149 but could not the understand the labels much even after reading the references.

All I could understand that P(primary) mass % + S(Secondary) mass % = 100. And the ABV I am getting at the most red line is like 70% as in the table.
Primary Secondary Tertiary Mix BP °C P BP °C S BP °C T BP °C P mass % S mass % T mass % Notes
Acetaldehyde 21 21 100 No water azeotrope
Ethyl formate Methanol 51 54.1 64.7 84 16
Methyl Acetate Methanol 53.8 57 64.7 81.3 18.7
Acetone Methanol 55.7 56.5 64.7 87.9 12.1
Methyl Acetate Water 56.1 57 100 95 5
Acetone 56.5 56.5 100 No water azeotrope
Methyl Acetate Ethanol 56.9 57 78.44 97 3
Ethyl Acetate Methanol 62.3 77.1 64.7 56 44
Methanol Isopropanol 64 64.7 82.5 80 20
Methanol 64.7 64.7 100 No water azeotrope
Ethyl Acetate Water 70.4 77.1 100 91.9 8.1
Ethyl Acetate Ethanol 71.8 77.1 78.44 69.2 30.8
Diacetyl Ethanol 73.9 88 78.44 53 47
Isopropyl acetate Isopropanol Water 75.5 101.6 82.5 100 76 13 11 Ternary azeotrope
Ethanol isopropyl acetate 76.8 78.44 88.4 53 47
Ethanol Methyl butyrate Water 77.62 78.44 102.34 100 56.63 34.88 8.49 Ternary azeotrope
Ethanol Methyl butyrate 78.13 78.44 102.34 80.78 19.22
Ethanol Water 78.29 78.44 100 95.68 4.32
Diacetyl Water 78.5 88 100 89.29 10.71
Isopropanol Water 80.4 82.5 100 87.7 12.3
N-Propyl acetate Water Propanol 82.2 101.6 100 97.3 59.5 21 19.5 Ternary azeotrope
N-Propyl acetate Water 82.4 101.6 100 86 14
Methyl butyrate Water 84.77 102.34 100 82.11 17.89
Propanol Water 88.24 97.3 100 71.03 28.97
Isobutanol Water 90 108 100 70 30
Isobutyl acetate Water 90.26 118.04 100 75.6 24.4
N-Butyl acetate Water N-Butanol 90.6 125.94 100 117.8 63 29 8 Ternary azeotrope
N-Butyl acetate Water 90.7 125.94 100 72.9 27.1
Ethyl butyrate Water 91.4 120.54 100 73.24 26.76
Butanol Water 92.4 117.8 100 55.5 44.5
N-Butyl acetate Water 92.98 125.94 100 69 31
Water Isoamyl alcohol Isoamyl acetate 93.6 100 130.54 142 44.8 31.2 24 Ternary azeotrope
Propyl butyrate Water 94.91 142.74 100 61.74 38.26
Isoamyl alcohol Water 95.31 130.54 100 51.33 48.67
Water Iso-butyric acid 99.3 100 154.5 79 21
Water Butyric acid 99.94 100 163.5 81.6 18.4
Water Propionic acid 99.98 100 141.1 82.3 17.7
Formic acid Water 107.3 100.8 100 77.5 22.5 Negative azeotrope
Acetic acid 118.1 118.1 100 No water azeotrope


The drops were not like drops but filled a litre or so. I was boiling 8 litres of 30% ABV.
At no time my ABV was >80. I use an optical ABV refractometer than has shown me 80 % in my Airstill (Pot still)
I use a 20 litre boiler with a 1400w hot plate.
I use recirculated water
My reflux still is here . viewtopic.php?t=76373
It has a very tightly packed 500mm column (With copper mesh)

Are these three different temps normal?

Which temp I should aim after the dephlagmator?

How do I get a higher ABV? I have tried running it slow as well. The Boiler vapour temp was like 80 C. I used a bimetallic thermometer for this.

Thanks in advance.

This topic has 26 more replies

You must be a registered member and logged in to view the replies in this topic.


Register Login
 
Post Reply