Mapp as a refrigerant?
 

Methly Acetate Propandine Stabilized

Which is just methane and propane? propane is already a great refrigerant, but methane is better(i think). So wouldnt this be better than propane and still easily available?

hmmm
 

Very interesting -- if you think about it, mapp would probably perform somewhere between pure R50 and the popular methane derivatives R12 and R22 - the mix of propane would help decrease the high pressure requirement that a pure methane system would need:

quoted from a basic refrigeration site:
----------------------------------------------------
R50(methane): this moderately light gas with a boiling point of -162C is the base compound for most of today’s refrigerants - in its pure form it is a bit too light(molecular weight 16) to work with outside of a cascade cooler. Though this can be used in a system of its own you will be needing pressures nearing the 450 mark on a warm day to liquefy. So overall a great additive or for use in a cascade cooler.

Unfortunately it seems that Mapp is trademarked and I can't find any detail about it's chemical properties or makeup (ie what if it's 99% propane and 1% methane)

In a non cascade system I think you'd need a hardcore compressor for mapp - again it all depends on the % makeup of propane to methane to other gasses in it. Hell it sure would be a fun experiment though

Any students out there that have access to a spectrum analyzer of some sort that could take apart Mapp gas for us?

Hehe, on this same thought how bout HELIUM as a refrigerant, also very readily available!! Boils at -268.6 °C OMG rar
Get a very strong compressor, a very small metering device, some titanium tubing and design a custom oil injection system to feed the compressor and you're in business....booya!

Try emailing them. Say you're interesting in evaluating it for some project.

Re: Mapp as a refrigerant?
 

Geez.

methyl acetate =! methane =! methyl acetylene

propadiene =! propane

MAPP = methyl acetylene propadiene

Mind the spelling. Every letter in organic chemistry means something.

Methyl acetate is the reeking stuff from fingernail polish remover.

Propadiene I don't know much about.

I've heard reports MAPP destroys copper, but nothing verified.

http://www.e-barnettww.com/MSDS/000429.pdf

At least it won't kill the **** out of you. OSHA PEL (Personnel exposure limit) is 1000 ppm, so you're probably safe with it if you use some common sense - well-ventilated area, some sort of facial protection, etc.

This has been your engineering safety brief.

Alchemy

Re: hmmm
 

It's not trademarked; it's a standard industrial mixture. Companies simply don't want to give the exact mixture of methyl acetylene to propadiene. I'm sure there's an MSDS somewhere that would tell you.

What makes you think so? The properties of methyl acetate are nothing like methane.

This is sorta overkill.

Alchemy

Sorry sir, I'm not sure exactly what I said to make you so angry - you sure did tear me apart but you didn't provide any useful or contradictory information about the topic at hand beyond saying 'I'm an idiot'

AND I have to point out that you are wrong...MAPP is a registered trademark of the BOC group, inc. I'm sure there's similar generic mixtures but the product MAPP (notice the little R in a circle always next to it) is not generic

I also have to disagree about the properties - I'm no chemist but I figured based on common sense that MAPP's properties would be somewhere between Methane and Propane - you are right that "methyl acetate =! methane =! methyl acetylene / propadiene =! propane" but please see below - I still don't think I was far off in my uneducated assumptions


Propane
-------------------
Molecular Weight: 44.097
Boiling Point: -43.67°F ( -42.04°C) @ 1 atm
Specific Gravity: 1.5223 At 70°F (21.1°C) @ 1 atm, Air = 1
Freezing/Melting Point: -305.84F (-187.69C) at 1 atm
Vapor Pressure: 109.73 psig, (756.56 kPa) at 70°F (21.2°)
Vapor Density: 0.110 lb./cu ft (1.1.77kg/CuM), At 70°F (21.1°C) @ 1 atm
Expansion Ratio: 1 to 290 at 70°F (21.1°C)

Methane
-------------------------------
Physical state (gas, liquid, solid) : Gas
Vapor pressure : Not Available
Vapor density (Air = 1) : Not Available
Evaporation point : Not Available
Boiling point : -161.5 oC
Freezing point : -182.5 oC
pH : Not Applicable
Specific gravity : 0.55

MAPP
------------------------------
Physical state (gas, liquid, solid) : Gas
Vapor pressure at 70oF : 97 psia
Vapor density (Air = 1) : Not Available
Evaporation point : Not Available
Boiling point : -48 to -23 oC
Freezing point : -120 oC
pH : Not Available
Specific gravity : 0.571 (Liquid)

So if you have some information that is relevant for this discussion and helps answer the original question please by all means post it - I did just see it mentioned somewhere that MAPP may be incompatible with copper and silver so that might rule it out in a standard system.