Removing Chlorophyll

Gray Wolf · Aug 17, 2018

Suggested by Pharmer Joe for post extraction removal of chlorophyll :

Materials needed:

Acetonitrile
Acetone
Graphite
Flash silica
Fritted funnel
Erlymeyer flask with vacuum side arm
Vacuum pump

Procedure

Dissolve oil in acetonitrile
Add 5% (oil wt) graphite and stir 1 hour
Make slurry with silica and acetonitrile
Set up filter apparatus
Pour silica slurry onto fritted funnel
When the solvent drains just above the bed surface; pour graphite mixture and apply gentle vacuum.
Clean equipment up afterwards with Acetone.

SkyHighLer · Aug 17, 2018

I ordered a liter of reagent grade (ACS) acetonitrile from Right Price Chemicals, $33.74 plus $15.78 shipping and handling, $49.52 total.

https://www.rightpricechemicals.com/buy-acetonitrile-online-reagent-acs-hplc.html

(I only bought this out of curiosity, and to ensure Right Price Chemicals is still a no hassle supply house.)

It's neither very polar or non-polar, between acetone and isopropyl alcohol.

Polarity table,

https://archive.org/stream/Solvents...rganic_Chemistry_Reichardt#page/n441/mode/2up

The FDA Q3C residual standard tables list it as Class 2 with a maximum residual recommendation of 490 ppm, that's why I didn't pursue it previously, it needs a thorough purge as you would with hexane, which has a max residual recommendation of 290 ppm.

https://www.fda.gov/downloads/drugs/guidances/ucm073395.pdf

troutman · Aug 17, 2018

Did any of you try phosphoric acid or sulfuric acid yet?

Chlorophyll Removal From Edible Oils

Abstract:

The chlorophyll content of canola oil, especially when extracted from frost-damaged seed is high, and results in dull,
dark brown oil unless very large quantities of bleaching clay are used. We found that treatment with phosphoric acid,
under vacuum in the absence of moisture precipitates most of the chlorophyll. At 140°C 2400mg/L phosphoric acid
precipitated 98% of the chlorophyll in canola oil after 15 minutes of gentle stirring under vacuum of ~30mmHg (4kPa).
Chlorophyll levels were reduced from 23.8mg/L to less than 0.5mg/L. This was further reduced to >0.05mg/L with
caustic refining and bleaching.

A similar reduction in chlorophyll level was obtained with 5000mg/L sulfuric acid at room temperature.

Chlorophyll Removal From Edible Oils

I tried sulfuric acid drain cleaner for a small test and what a freaking wild precipitation reaction. :biggrin:

My fun with sulfuric acid. Next time, I use clean sulfuric acid and in a more scientific way.

Gray Wolf · Aug 18, 2018

troutman said:
Did any of you try phosphoric acid or sulfuric acid yet?

Chlorophyll Removal From Edible Oils

Abstract:

The chlorophyll content of canola oil, especially when extracted from frost-damaged seed is high, and results in dull,
dark brown oil unless very large quantities of bleaching clay are used. We found that treatment with phosphoric acid,
under vacuum in the absence of moisture precipitates most of the chlorophyll. At 140°C 2400mg/L phosphoric acid
precipitated 98% of the chlorophyll in canola oil after 15 minutes of gentle stirring under vacuum of ~30mmHg (4kPa).
Chlorophyll levels were reduced from 23.8mg/L to less than 0.5mg/L. This was further reduced to >0.05mg/L with
caustic refining and bleaching.

A similar reduction in chlorophyll level was obtained with 5000mg/L sulfuric acid at room temperature.

Chlorophyll Removal From Edible Oils

I tried sulfuric acid drain cleaner for a small test and what a freaking wild precipitation reaction.
My fun with sulfuric acid. Next time, I use clean sulfuric acid and in a more scientific way.

View Image

No, but did de-gum with citric acid, which also removes some of the chlorophyll or de-protonates it into pheophytin.

Although I've never tried it, EugeneOregon used to post on this site and offered the following on another forum. I notice he seems to have discontinued posting here, so not available for questions.

From EugeneOregon:

Take some rubbing alcohol at 70/30 isopropyl alcohol to water and put your compound into it. Then bring the solution to a low boil and boil the compound. As you boil the isopropyl alcohol will deplete and water will become dominant.

You will see then that the oil is mostly just rolling around in water. The water will be milk white if terpenes are present. Isopropyl alcohol forms an azeotrope with water so will not be boiled away completely. This water and alcohol will swell the gunk including the green chlorophyll stuff.

Then re-dissolve it all in 70/30 rubbing alcohol at room temp.

Then put a few inches of aluminum oxide 220-240 grit into a Buchner funnel and prewet it with water. Then pull the solution through the prewetted aluminum oxide. The green chlorophyll and a BUNCH of "waxes" will not be able to pass the top of the aluminum oxide. This will remove the chlorophyll.

troutman · Aug 18, 2018

Before I had fun with the sulfuric acid I tried 50mL of Kosher Salt in 300 mL of distilled water.
I can say I had lots of fun even though I didn't finish the procedure. Next time, I go all the
way with new ideas and lab equipment.

The top layer in my separatory funnel is 300mL of n-hexane.

50 mL of Kosher Salt:

Before Saltwater Addition:

After Saltwater Addition:

After Saltwater Addition Closeup:

From what I read, the yellow color in my separatory funnel is phythol from the degradation of the chlorophyll.

Gray Wolf · Aug 18, 2018

troutman said:
Before I had fun with the sulfuric acid I tried 50mL of Kosher Salt in 300 mL of distilled water.
I can say I had lots of fun even though I didn't finish the procedure. Next time, I go all the
way with new ideas and lab equipment.

The top layer in my separatory funnel is 300mL of n-hexane.

50 mL of Kosher Salt:

View Image

Before Saltwater Addition:

View Image

After Saltwater Addition:

View Image

After Saltwater Addition Closeup:

View Image

From what I read, the yellow color in my separatory funnel is phythol from the degradation of the chlorophyll.

Probably nore likely pheophytin.

troutman · Aug 18, 2018

Gray Wolf said:
Probably nore likely pheophytin.

OK, I'm still learning about the breakdown plant products.

But is says in Wikipedia that pheophytin can be produced from chlorophyll by treatment
with a weak acid, producing a dark bluish waxy pigment. I don't have any blueish color
in my separatory funnel.

https://en.wikipedia.org/wiki/Pheophytin

Phytol on the other hand is yellowish.

Phytol is a starting material, also referred to as a precursor, for the formation of vitamin E and K. Because there is a yellow pigment present in this diterpenol, tinctures which are being treated with heat, often have a yellow color. This occurs because the present chlorophyll is being broken down.

Gray Wolf · Aug 19, 2018

troutman said:
OK, I'm still learning about the breakdown plant products.

But is says in Wikipedia that pheophytin can be produced from chlorophyll by treatment
with a weak acid, producing a dark bluish waxy pigment. I don't have any blueish color
in my separatory funnel.

https://en.wikipedia.org/wiki/Pheophytin

Phytol on the other hand is yellowish.

Ummmm, Wiki and other sources don't appear to agree on the color of pheophytin. If the magnesium ion is removed, where is the blue color coming from?

https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/pheophytin

Chlorophyl

Chlorophyl pigments are present in all green vegetables, but canning leads to breakdown with the associated color change from bright green to olive green or brown. The chlorophyl is converted to pheophytin by the loss of magnesium ions (Mg2+), with heat and low pH during processing greatly accelerating this change. The addition of alkaline salts in the canning liquor to maintain a pH of 6.2–7.0 and high-temperature, short-time (HTST) processing have both been used in canning to reduce chlorophyl degradation. (See CHLOROPHYL.)

Thanks for pointing out the association between chlorophyll and phytol. I was aware of its presence, color, and properties, but not that it was a degradation byproduct of chlorophyll. :tiphat:

troutman · Aug 19, 2018

We're all here to learn so why not share info and learn together. :huggg:

Phytol is attached to one end of the chlorophyll molecule via a carboxylic group
and all it takes is a simple hydrolysis and off it goes.

Treatment of cholorophyll-a with acid removes the magnesium ion replacing it with two hydrogen atoms
giving an olive-brown solid, phaeophytin-a. Hydrolysis of this (reverse of esterification) splits off phytol
and gives phaeophorbide-a. Similar compounds are obtained if chlorophyll-b is used.

Overall reaction scheme for the hydrolysis of chlorophyll.

Chlorophyll can also be reacted with a base which yields a series of phyllins, magnesium
porphyrin compounds. Treatment of phyllins with acid gives porphyrins.

Overall scheme for the reaction of alkaline with chlorophyll.

From here:

https://www.ch.ic.ac.uk/local/projects/steer/chloro.htm

In one of my Mad Scientist experiments, I also exposed some Cannabis extract to sodium hydroxide
and I bet that removed the magnesium atom in the chlorophyll molecule. I forget now what was the
result. Not sure if I documented it.

All I know is nobody will ever say I don't have fun with my chemistry equipment. :biggrin:

I think this is what phaeophytin looks like in the bottom layer of my separatory funnel according
to the description above (i.e olive-brown).

Gray Wolf · Aug 20, 2018

troutman said:
We're all here to learn so why not share info and learn together.

Phytol is attached to one end of the chlorophyll molecule via a carboxylic group
and all it takes is a simple hydrolysis and off it goes.

Treatment of cholorophyll-a with acid removes the magnesium ion replacing it with two hydrogen atoms
giving an olive-brown solid, phaeophytin-a. Hydrolysis of this (reverse of esterification) splits off phytol
and gives phaeophorbide-a. Similar compounds are obtained if chlorophyll-b is used.

Overall reaction scheme for the hydrolysis of chlorophyll.

View Image

Chlorophyll can also be reacted with a base which yields a series of phyllins, magnesium
porphyrin compounds. Treatment of phyllins with acid gives porphyrins.

Overall scheme for the reaction of alkaline with chlorophyll.

View Image

From here:

https://www.ch.ic.ac.uk/local/projects/steer/chloro.htm

In one of my Mad Scientist experiments, I also exposed some Cannabis extract to sodium hydroxide
and I bet that removed the magnesium atom in the chlorophyll molecule. I forget now what was the
result. Not sure if I documented it.

All I know is nobody will ever say I don't have fun with my chemistry equipment.

I think this is what phaeophytin looks like in the bottom layer of my separatory funnel according
to the description above (i.e olive-brown).

View Image

Thanks for the Phytol education brother! :tiphat:

I agree that the brown in the bottom of the separatory funnel is most likely paeophytin/pheophytin. I've seen it spelled both ways.

I dug through my library for an old 60's article on making "Red Oil", but couldn't find it. As memory serves me, they were deprotonating with Drano (sodium hydroxide), but I don't remember what else they did besides neutralize it.

troutman · Aug 20, 2018

I can't wait to put my clevenger apparatus and esssential oil & water apparatus to work later on.
I just need some new PTFE joint sleeves and I'm all set to go. I'm going wait until the cool weather
returns as I don't like playing with volatile solvents in Summer for obvious reasons.

troutman · Aug 20, 2018

Gray Wolf said:
Thanks for the Phytol education brother!

I agree that the brown in the bottom of the separatory funnel is most likely paeophytin/pheophytin. I've seen it spelled both ways.

I dug through my library for an old 60's article on making "Red Oil", but couldn't find it. As memory serves me, they were deprotonating with Drano (sodium hydroxide), but I don't remember what else they did besides neutralize it.

I just found a 1940 Red Oil article by Roger Adams.

Isolation of Cannabinol, Cannabidiol and Quebrachitol from Red Oil of Minnesota Wild Hemp

https://pubs.acs.org/doi/abs/10.1021/ja01865a080

Gray Wolf · Aug 20, 2018

troutman said:
I just found a 1940 Red Oil article by Roger Adams.

Isolation of Cannabinol, Cannabidiol and Quebrachitol from Red Oil of Minnesota Wild Hemp

https://pubs.acs.org/doi/abs/10.1021/ja01865a080

Good score! Not the same ghetto process article that sought, but notice he referenced Todd, so I rechecked Larry S. Todd's book Dr Atomics Marijuana Multiplier (1970), but alas it only had isomerizing with an acid (H2SO4), and L. Todd may have been a little young prior to 1940.

I'll keep looking, and if I find it, I'll share. :tiphat:

SkyHighLer · Aug 20, 2018

Gray Wolf said:
Suggested by Pharmer Joe for post extraction removal of chlorophyll :

Materials needed:

Acetonitrile
Acetone
Graphite
Flash silica
Fritted funnel
Erlymeyer flask with vacuum side arm
Vacuum pump

Procedure

Dissolve oil in acetonitrile
Add 5% (oil wt) graphite and stir 1 hour
Make slurry with silica and acetonitrile
Set up filter apparatus
Pour silica slurry onto fritted funnel
When the solvent drains just above the bed surface; pour graphite mixture and apply gentle vacuum.
Clean equipment up afterwards with Acetone.

SkyHighLer said:
I ordered a liter of reagent grade (ACS) acetonitrile from Right Price Chemicals, $33.74 plus $15.78 shipping and handling, $49.52 total.

https://www.rightpricechemicals.com/buy-acetonitrile-online-reagent-acs-hplc.html

(I only bought this out of curiosity, and to ensure Right Price Chemicals is still a no hassle supply house.)

It's neither very polar or non-polar, between acetone and isopropyl alcohol.

Polarity table,

https://archive.org/stream/Solvents...rganic_Chemistry_Reichardt#page/n441/mode/2up

The FDA Q3C residual standard tables list it as Class 2 with a maximum residual recommendation of 490 ppm, that's why I didn't pursue it previously, it needs a thorough purge as you would with hexane, which has a max residual recommendation of 290 ppm.

https://www.fda.gov/downloads/drugs/guidances/ucm073395.pdf

Am I to assume pure graphite is pure graphite?

From eBay:

Pure Graphite Powder Quart/$16.99

https://www.ebay.com/itm/Pure-Graph...821818?hash=item3aab86807a:g:Mk4AAOSwFqpbab27

"Flash silica" at Sigma-Aldrich,

https://www.sigmaaldrich.com/catalog/product/supelco/97728u?lang=en&region=US

Seems to be the same as HiMedia's GRM7481 available via Amazon, 500g/$27.

https://www.amazon.com/gp/product/B00DYO51I0/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

https://www.himedialabs.com/TD/GRM7481.pdf

Gray Wolf · Aug 20, 2018

SkyHighLer said:
Am I to assume pure graphite is pure graphite?

Pharmer Joe says yes.

Pastelero · Aug 22, 2018

@ GrayWolf: Thank you for your new imput, highly appreciated.

Does it have to be Acetonitrile, or do other solvents (Ethanol, Heptane) work as well?

Or does only Acetonitrile in combination with graphite the trick?

SkyHighLer · Aug 23, 2018

SkyHighLer said:
I ordered a liter of reagent grade (ACS) acetonitrile from Right Price Chemicals, $33.74 plus $15.78 shipping and handling, $49.52 total.

https://www.rightpricechemicals.com/buy-acetonitrile-online-reagent-acs-hplc.html

(I only bought this out of curiosity, and to ensure Right Price Chemicals is still a no hassle supply house.)

It's neither very polar or non-polar, between acetone and isopropyl alcohol.

Polarity table,

https://archive.org/stream/Solvents...rganic_Chemistry_Reichardt#page/n441/mode/2up

The FDA Q3C residual standard tables list it as Class 2 with a maximum residual recommendation of 490 ppm, that's why I didn't pursue it previously, it needs a thorough purge as you would with hexane, which has a max residual recommendation of 290 ppm.

https://www.fda.gov/downloads/drugs/guidances/ucm073395.pdf

I didn't open an account, I click-on ordered, immediately paying with a credit card, I immediately received an order confirmation, a few days later the order was processed and I received a tracking number, a few more days later and the package was left at my front door.

Evaporates quickly, the mild odor reminds me of a cross of isopropyl alcohol and ethyl acetate.

Gray Wolf · Aug 24, 2018

Pastelero said:
@ GrayWolf: Thank you for your new imput, highly appreciated.

Does it have to be Acetonitrile, or do other solvents (Ethanol, Heptane) work as well?

Or does only Acetonitrile in combination with graphite the trick?

Acetonitile is the only one I am aware of using that procedure. Perhaps one of our online chemistry brain trusts can chime in??

scrogrow · Aug 24, 2018

Gray Wolf said:
Good score! Not the same ghetto process article that sought, but notice he referenced Todd, so I rechecked Larry S. Todd's book Dr Atomics Marijuana Multiplier (1970), but alas it only had isomerizing with an acid (H2SO4), and L. Todd may have been a little young prior to 1940.

I'll keep looking, and if I find it, I'll share.

Ah wolf man I've literally just suggested someone look you up and read your posts

troutman · Aug 24, 2018

What's the level of chlorophyll left after doing this acetonitile method?

Has anyone done this yet? Pics would be nice. :tiphat:

Removing Chlorophyll

A Posse ad Esse. From Possibility to realization.

Got me a stone bad Mana

Seed Whore

A Posse ad Esse. From Possibility to realization.

Seed Whore

A Posse ad Esse. From Possibility to realization.

Seed Whore

A Posse ad Esse. From Possibility to realization.

Seed Whore

A Posse ad Esse. From Possibility to realization.

Seed Whore

Seed Whore

A Posse ad Esse. From Possibility to realization.

Got me a stone bad Mana

Attachments

A Posse ad Esse. From Possibility to realization.

Active member

Got me a stone bad Mana

Attachments

A Posse ad Esse. From Possibility to realization.

Active member

Seed Whore