I will admit to my total ignorance when it comes to pressurized storage containers and could use some help. I have had no luck trying to find answers to most of my questions on the net.
Here is an idea I have had for years and wondering if it can be safely pulled off. The goal would be to have a pressurized utility sprayer that I can carry around with me for spraying roundup etc. I am tired of pumping my 2-3 gallon sprayer every several minutes. I have a 5-gallon backpack model but once full I have a hard time getting it on/off by myself and it hurts my lower back as I walk around my 6 acres. I like the idea of a smaller, pressurized, hand held 2-3 gallon sprayer. I know they make battery powered units but I like to experiment & was wondering if an empty propane tank be repurposed (refilled with air) to provide the 10 PSI that I need? I do not think the high pressure paint-ball tanks is what I want as they are thousands of PSI and expensive.
I have long wanted to take an empty (small torch sized) 1-pound propane tank and refill it with air via my shop air compressor and try out my idea. I would attach a regulator to knock down the high pressure air down to ~10 PSI.
My 1st & most important question is what PSI can these small 1-pound propane tanks hold safely? The last thing I would want is to set my shop compressor too high & have a catastrophic failure due to too much pressure while refilling it. The next question would be where can I get a low-pressure regulator with a gauge so I can dial in the PSI into my 2-3 gallon sprayer.