Sub Critical CO2 Extractor

Building projects are full of amazing learning lessons…. If you ever want to know what its like to be kicked in the balls without foot to crotch, read on.

So this project resulted in being a large paper weight… So I am a Washingtonian, and we love our coffee (StarBucks anyone?), but all of the great roasts contain caffeine, which is not suitable for a bedtime drink. – Market Idea – Why not make a machine to remove the caffeine from the beans, this would be a small appliance that could sit next to a coffee machine and remove the caffeine before grind and strain.

There are a couple of basic ways to remove caffeine, soaking the beans in a solvent is the normal route but who wants to add more exposure to chemicals like methylene chloride or ethyl acetate. Why not use CO2? In its liquid form, it is an amazing solvent and the body regularly produces this chemical so it should be safe.

Sometime the excitement of building something blinds you to real world obstacles. So, long story short I built the following:

Machine Specs:

  1. Machine dimension: 1′ x 3′ x 2.5′
  2. 120v power
  3. Automated approach: Valves are all motorized, so the only manual actions needed are to add beans to cylinder.
  4. Automated recovery of CO2, closed system, so the CO2 would enter the chamber, pressurized to a liquid state, soak, then vaporized to be compressed and re-liquefied.

Everything was going great until I was informed that the requirements for legally running the machine were a little to high. Add that with the negative connotation of what CO2 extraction is used for in other industries, makes finding reputable investors more of a project into its own. Ugh!