4 replies to this topic

[manni]

Hi all,

We actualy want to Extract Ethanol upto 99.5% purity using probably molecular sieves. Till now we know that initial 90% ethanol can be easily Purified upto 98% purity simply using Fractional Distillation. But the remaining 2% water (moisture) is unable to be separated using the same. So Molecular sieves may be used. So anyone with a good background in molecular sieves may please come forward to help us about the Related Specifications and may be more if interested.

Thanks in Advance

[riven]

Hi all,

We actualy want to Extract Ethanol upto 99.5% purity using probably molecular sieves. Till now we know that initial 90% ethanol can be easily Purified upto 98% purity simply using Fractional Distillation. But the remaining 2% water (moisture) is unable to be separated using the same. So Molecular sieves may be used. So anyone with a good background in molecular sieves may please come forward to help us about the Related Specifications and may be more if interested.

Thanks in Advance

Essentially you want to break the azeotrope of ethanol-water-x system you have? I assume you are using a vacuum column (leading to the 2% azeotrope instead of the typical 4.4%) or that there is a third component.
Breaking the azoetrope can be achieved in several ways: azeotropic distillation by adding an entrianer or by using a hybrid process (distillation + other process). These other process could include pervaporation/vapour permeation or molecular sieves.

In either cases to design specifications such as capacities, temperatures and product spec are required before i can help you.

[pawan]

U can use 3A molecular Sieve for this purpose. I am using it for the same for removing water from 8% Wt to 99.5% Purity.
What is the size of plant U are planning for this. I mean What is the Alcohol feed rate (Wet) with mositure content.
Probably I can help U.

[manni]

U can use 3A molecular Sieve for this purpose. I am using it for the same for removing water from 8% Wt to 99.5% Purity.
What is the size of plant U are planning for this. I mean What is the Alcohol feed rate (Wet) with mositure content.
Probably I can help U.

hi Pawan,

Actually we are taking the initial feed rate for fractional distillation to be 36000 kg/hr having initial alcohol conc. => 0.777 (mol/mol) . Using the McCabe Thiele Method, we found out approx. 9 trays to be required to concentrate the Purity to be 89.5% (mol/mol). And the Distillate flow rate was calculated to be 33784.2 kg/hr . So now using a 3 A (angstrom) size Molecular sieve, what are the Other Requirements we would need to follow the process ahead. Also if you could Please tell the Cost of Molecular sieves available for this process, it would help.

Thnks
manni

[pawan]

This is a much higher capacity & Sieves may not be profitable comapred to conventional distillation. I need to explore additional options. Tell me your location.