ethylene glycol vs. propylene glycol
Question:
I am a staunch promoter of protecting the environment and I don’t change my stance depending on what I’m doing or who I am affiliated with. The beauty of the natural world is too important to my sanity to do otherwise. I was reading an article about the SR-22 (nice plane) and realized that we still use ethylene glycol in icing systems. This stuff is really very toxic. It kills plants and animals. It even has an enticing smell and flavor. Does anyone know why proplyene glycol cannot be used instead? Here is the current recipe for icing systems: 85 parts of ethylene glycol, 5 parts of iso-propyl alcohol and 10 parts water. I can’t believe the performance is much different since propylene glycol is used in automotive applications.
Response:
Does anyone know why proplyene glycol cannot be used instead?
I asked a chemical engineer friend of mine about the difference between ethylene and propylene glycol. What I can remember of his explanation indicated that propylene glycol wasn’t really that much better. For what it’s worth, though, the stuff we carry on board in our deice cans is propylene glycol. — Larry Fransson Seattle, WA
Response:
What do you use for deice cans? Mike MU-2
– Hide quoted text — Show quoted text – Does anyone know why proplyene glycol cannot be used instead? I asked a chemical engineer friend of mine about the difference between ethylene and propylene glycol. What I can remember of his explanation indicated that propylene glycol wasn’t really that much better. For what it’s worth, though, the stuff we carry on board in our deice cans is propylene glycol. — Larry Fransson Seattle, WA
Response:
Propylene glycol is used in ice cream, don’t try that with ethylene glycol! Mike MU-2
– Hide quoted text — Show quoted text – Does anyone know why proplyene glycol cannot be used instead? I asked a chemical engineer friend of mine about the difference between ethylene and propylene glycol. What I can remember of his explanation indicated that propylene glycol wasn’t really that much better. For what it’s worth, though, the stuff we carry on board in our deice cans is propylene glycol. — Larry Fransson Seattle, WA
Response:
Isopropyl alcohol isn’t all that good for you either. There’s a reason it’s used as an antiseptic.
| Propylene glycol is used in ice cream, don’t try that with ethylene glycol! | | Mike | MU-2 |
| | Does anyone know why proplyene glycol | cannot be used instead? | | I asked a chemical engineer friend of mine about the difference between | ethylene and propylene glycol. What I can remember of his explanation | indicated that propylene glycol wasn’t really that much better. | | For what it’s worth, though, the stuff we carry on board in our deice | cans is propylene glycol. | | — | Larry Fransson | Seattle, WA | |
Response:
This stuff is really very toxic. It kills plants and animals.
Really? At what dose? Oral, subcutaneous, inhaled, topical… ? Any data to back this up? Define ‘toxic’ in this sense? Before you go off on something this silly, think it through. Glycol is quite poisonous *if you drink it*. The amount used for deice is completely harmless after it’s stirred into the slipstream and spread out over a gazillion miles. If you wanna equate ‘toxic’ with ‘dangerous’, then quit drinking water. People die from an overdose of water all the time… ‘toxic’ stuff, right? The avgas you carry around is significantly more dangerous than glycol in several different respects. -Dave Russell Uninformed fear, be it ecology or aviation, leads to less-than-good ideas. Don’t be a Daley.
Response:
Does anyone know why proplyene glycol cannot be used instead? I asked a chemical engineer friend of mine about the difference between ethylene and propylene glycol. What I can remember of his explanation indicated that propylene glycol wasn’t really that much better.
Better in what regard? Better for de-icing? Or better as in "not that much less toxic than ethylene glycol"? If it’s the first one then then there’s no reason to use ethylene glycol. If it’s the second then you’re wrong. There are huge differences in the toxicity. Ethylene glycol is very nasty stuff. – Hide quoted text — Show quoted text – For what it’s worth, though, the stuff we carry on board in our deice cans is propylene glycol.
Response:
This stuff is really very toxic. It kills plants and animals. Really? At what dose? Oral, subcutaneous, inhaled, topical… ? Any data to back this up? Define ‘toxic’ in this sense?
There’s a lot of data on ethylene glycol. Toxic is a good word that doesn’t change meaning with context. Since you’re from AOL you may be internet challenged so here’s a link for you: www.atsdr.cdc.gov Before you go off on something this silly, think it through. Glycol is quite poisonous *if you drink it*. The amount used for deice is
Get your self some data yourself. You’re wrong. completely harmless after it’s stirred into the slipstream and spread out over a gazillion miles.
Don’t forget about de-icing on the ground. If you wanna equate ‘toxic’ with ‘dangerous’, then quit drinking water. People die from an overdose of water all the time… ‘toxic’ stuff, right?
Really happens all the time? Now this is something silly. You’re starting to sound like part of the problem. The avgas you carry around is significantly more dangerous than glycol in several different respects.
Just to let you know, this is not an argument. This is a "straw man". – Hide quoted text — Show quoted text – -Dave Russell Uninformed fear, be it ecology or aviation, leads to less-than-good ideas. Don’t be a Daley.
Response:
Well, you see, ethylene glycol is better because it is also useful for getting rid of those damn cats that hang around the airport and insist on climbing on cars and airplanes and scratching the paint… So much quieter than shooting them with a .45 or 12-gauge… <evil-grin
Response:
Isopropyl alcohol isn’t all that good for you either. There’s a reason it’s used as an antiseptic.
Well, it’s "denatured" — which is to say, it contains a poison. Other than that deliberate toxicity, it’s pretty much the same as vodka. By the way, my daughter used to use Popov vodka as anti-freeze in the water lines of her boat. It was cheaper than the commercial anti-freeze and didn’t leave an aftertaste when it was flush out. all the best — Dan Ford (email: web AT danford.net) see the Warbird’s Forum at http://www.danford.net/index.htm Vietnam | Flying Tigers | Pacific War | Brewster Buffalo | Piper Cub
Response:
Propylene glycol is used in ice cream, don’t try that with ethylene glycol!
It’s also used in some soaps, shampoos, and is known to cause skin irritation in some people. Many products humans use contain this substance and for the most part it’s considered safe for our usage.
Response:
| | | completely harmless after it’s stirred into the slipstream and spread | out over a gazillion miles. | | Don’t forget about de-icing on the ground. | A small nit: you don’t run your de-icing system on the ground. The de-icing system only works for a few minutes as it is. If you have ice on the ground you need to find some other way to remove it, or you won’t have the de-icing system in the air where you really need it.
Response:
What do you use for deice cans?
One of our former pilots put ours together. He started with a 2 gallon metal spray can. He put an electric heater (I think it came from an auto parts store) on the bottom of the can. He got rid of the hose that came with the can and put on a heavier coiled hose with a quick disconnect fitting at the discharge end. It looks like he used the spray wand that came with the can, but he threaded a quick disconnect fitting into it and put a different nozzle on it. Then he packaged the whole thing up in a custom made nylon bag. It’s pretty slick – certainly better than the plastic cans we had been using. The bag is designed to hold the wand and if you clear the hose and then disconnect it, you don’t get glycol running everywhere. The whole thing is also a lot smaller and easier to wrangle in and out of the back of the aiplane. We fill the whole thing with 100% glycol, use about half of it, then fill it with water before continuing. One important lesson we have learned recently: We’ll probably have to put a temperature switch on the can to limit the maximum temperature. We’ve messed up a couple of the cans due to pumps that got stuck in the can. From what we can determine, the glycol got too hot for the pump (made of poly-somethingorother) and the pressure in the tank caused the pump to collapse and get stuck. The guy who built the tanks said that full of glycol, they’d heat up to 140 F in about 45 minutes. We’re thinking that even 100 degrees should be plenty, and should prevent similar problems. — Larry Fransson Seattle, WA
Response:
Uh, you are thinking of ethyl alcohol as drinkable. Isopropyl is sometimes used to "denature " ethyl alcohol. Vodka is pretty much ethyl alcohol. Isopropyl alcohol will kill you, as will methyl alcohol and most of the others. Leo
– Hide quoted text — Show quoted text – Isopropyl alcohol isn’t all that good for you either. There’s a reason it’s used as an antiseptic. Well, it’s "denatured" — which is to say, it contains a poison. Other than that deliberate toxicity, it’s pretty much the same as vodka. By the way, my daughter used to use Popov vodka as anti-freeze in the water lines of her boat. It was cheaper than the commercial anti-freeze and didn’t leave an aftertaste when it was flush out. all the best — Dan Ford (email: web AT danford.net) see the Warbird’s Forum at http://www.danford.net/index.htm Vietnam | Flying Tigers | Pacific War | Brewster Buffalo | Piper Cub
Response:
Thanks. My problem is usually falling snow at temperatures around freezing. By the time the plane is pulled out of the hanger, engines started and clearance recieved , there is some question as to whether the accumulated snom will blow off by rotation speed. I was thinking about spraying non-heated propylene glycol on the lifting surfaces. Mike MU-2
– Hide quoted text — Show quoted text – What do you use for deice cans? One of our former pilots put ours together. He started with a 2 gallon metal spray can. He put an electric heater (I think it came from an auto parts store) on the bottom of the can. He got rid of the hose that came with the can and put on a heavier coiled hose with a quick disconnect fitting at the discharge end. It looks like he used the spray wand that came with the can, but he threaded a quick disconnect fitting into it and put a different nozzle on it. Then he packaged the whole thing up in a custom made nylon bag. It’s pretty slick – certainly better than the plastic cans we had been using. The bag is designed to hold the wand and if you clear the hose and then disconnect it, you don’t get glycol running everywhere. The whole thing is also a lot smaller and easier to wrangle in and out of the back of the aiplane. We fill the whole thing with 100% glycol, use about half of it, then fill it with water before continuing. One important lesson we have learned recently: We’ll probably have to put a temperature switch on the can to limit the maximum temperature. We’ve messed up a couple of the cans due to pumps that got stuck in the can. From what we can determine, the glycol got too hot for the pump (made of poly-somethingorother) and the pressure in the tank caused the pump to collapse and get stuck. The guy who built the tanks said that full of glycol, they’d heat up to 140 F in about 45 minutes. We’re thinking that even 100 degrees should be plenty, and should prevent similar problems. — Larry Fransson Seattle, WA
Response:
– Hide quoted text — Show quoted text – | | | completely harmless after it’s stirred into the slipstream and spread | out over a gazillion miles. | | Don’t forget about de-icing on the ground. | A small nit: you don’t run your de-icing system on the ground. The de-icing system only works for a few minutes as it is. If you have ice on the ground you need to find some other way to remove it, or you won’t have the de-icing system in the air where you really need it.
And since we’re nitting, alcohol/glycol is used as an anti-ice. Your de-icing on the ground is usually accomplished with heat and the alcohol/glycol is to keep the melted ice (water) from refreezing.
Response:
Doesn’t vodka help lean out the mix? And provide extra warmth of you have to do a forced landing in the winter? And help start a signal fire? And help make friends with the various large (and usually carnivorous) wildlife? Come to think of it, vodka probably belongs on the equipment list for a winter survival pack. 
| | Isopropyl alcohol isn’t all that good for you either. There’s a reason it’s | used as an antiseptic. | | Well, it’s "denatured" — which is to say, it contains a poison. Other | than that deliberate toxicity, it’s pretty much the same as vodka. | | By the way, my daughter used to use Popov vodka as anti-freeze in the | water lines of her boat. It was cheaper than the commercial | anti-freeze and didn’t leave an aftertaste when it was flush out. | | all the best — Dan Ford (email: web AT danford.net) | | see the Warbird’s Forum at http://www.danford.net/index.htm | Vietnam | Flying Tigers | Pacific War | Brewster Buffalo | Piper Cub
Response:
Isopropyl alcohol isn’t all that good for you either. There’s a reason it’s used as an antiseptic.
Yeh, but it doesn’t taste good. Ethylene glycol does. This doesn’t matter if you don’t mind poisoning the local animal life, I suppose. George Patterson "Cuius testiculos habes, habeas cardia et cerebellum." – When you have their full attention in your grip, their hearts and minds will follow.
Response:
If you wanna equate ‘toxic’ with ‘dangerous’, ….
Nobody wants to do that. "Toxic" has a very rigorous definition – it is poisonous. Water is not toxic. George Patterson "Cuius testiculos habes, habeas cardia et cerebellum." – When you have their full attention in your grip, their hearts and minds will follow.
Response:
Well, you see, ethylene glycol is better because it is also useful for getting rid of those damn cats that hang around the airport and insist on climbing on cars and airplanes and scratching the paint… So much quieter than shooting them with a .45 or 12-gauge… <evil-grin
Works on deer, too. George Patterson "Cuius testiculos habes, habeas cardia et cerebellum." – When you have their full attention in your grip, their hearts and minds will follow.
Response:
- Hide quoted text — Show quoted text – | | | completely harmless after it’s stirred into the slipstream and spread | out over a gazillion miles. | | Don’t forget about de-icing on the ground. | A small nit: you don’t run your de-icing system on the ground. The de-icing system only works for a few minutes as it is. If you have ice on the ground you need to find some other way to remove it, or you won’t have the de-icing system in the air where you really need it. And since we’re nitting, alcohol/glycol is used as an anti-ice. Your de-icing on the ground is usually accomplished with heat and the alcohol/glycol is to keep the melted ice (water) from refreezing.
Large transports are de-iced with glycol based products Lots of airports even use glycol based products on runways. Ethylene glycol is being replaced, but not everywhere, yet.
Response:
Isopropyl alcohol isn’t all that good for you either. There’s a reason it’s used as an antiseptic. Well, it’s "denatured" — which is to say, it contains a poison. Other than that deliberate toxicity, it’s pretty much the same as vodka.
You’ve been drinking it lately, have you? Sounds like you’re getting some really cheap vodka. – Hide quoted text — Show quoted text – By the way, my daughter used to use Popov vodka as anti-freeze in the water lines of her boat. It was cheaper than the commercial anti-freeze and didn’t leave an aftertaste when it was flush out. all the best — Dan Ford (email: web AT danford.net) see the Warbird’s Forum at http://www.danford.net/index.htm Vietnam | Flying Tigers | Pacific War | Brewster Buffalo | Piper Cub
Response:
" And since we’re nitting, alcohol/glycol is used as an anti-ice. Your de-icing on the ground is usually accomplished with heat and the alcohol/glycol is to keep the melted ice (water) from refreezing. Large transports are de-iced with glycol based products
HEATED glycol based products 
– Hide quoted text — Show quoted text – Lots of airports even use glycol based products on runways. Ethylene glycol is being replaced, but not everywhere, yet.
Response:
Don’t forget about de-icing on the ground. The only good point you made. My doctorate is in organic chemistry; my day job is pharmaceutical research. Please don’t tell me to go read some web page for tox data… we worry about things like this every day. Again, fear of something you don’t understand leads to *poor* choices in action and policy. There are many examples of ignorant fear, often fanned by the ignorant news media, pushing for a solution to a problem that sounds good to the lay person but, in reality, makes things worse. Aviation is often a victim of this type of nonsense, with Mayor Daley’s bulldozers being the most recent and obvious example. History is replete with the same, sorry type of story in many fields. Power lines, paper fast food wrappers, magnetic fields… there’s a long list. Rational risk assessment would indicate that there are more important things to worry about than the ethylene glycol used for anti-ice systems. If you feel strongly about it, fine, then don’t use it. But please don’t try to tell me why I shouldn’t. -Dave Russell 8KCAB (obviously a huge glycol user
Response:
Don’t forget about de-icing on the ground. The only good point you made.
And you missed it the first time around…. My doctorate is in organic chemistry; my day job is pharmaceutical
Having a doctorate in OChem is meaningless, you no doubt spent years studying some excruciating detail that no one cares much about. You still haven’t provided any facts toward your argument. research. Please don’t tell me to go read some web page for tox data… we worry about things like this every day.
Maybe you should follow that link. Did you study ethylene glycol toxicity? Again, fear of something you don’t understand leads to *poor* choices in action and policy. There are many examples of ignorant fear, often fanned by the ignorant news media, pushing for a solution to a problem that sounds good to the lay person but, in reality, makes things worse.
Don’t look now but your ignorant fear is showing. Aviation is often a victim of this type of nonsense, with Mayor Daley’s bulldozers being the most recent and obvious example. History is replete with the same, sorry type of story in many fields. Power lines, paper fast food wrappers, magnetic fields… there’s a long list. Rational risk assessment would indicate that there are more important things to worry about than the ethylene glycol used for anti-ice
Again your ignorance is blinding you. You don’t know anything about this topic you just feel you should respond because you have a PhD in ochem. systems. If you feel strongly about it, fine, then don’t use it. But please don’t try to tell me why I shouldn’t.
Never told anyone what they should or shouldn’t use. You’re having a hard time staying on track and on topic. I’ll give you the benefit of a doubt though since your handle shows you from AOL. Use whatever you want and do what ever you want to your environment. – Hide quoted text — Show quoted text – -Dave Russell 8KCAB (obviously a huge glycol user
