The technology of ethylene absorption with commercially existing potassium permanganate absorbents such as Bi-On® is an effective method to maintain apple quality during cold storage. The high rate of ethylene production of apple is a challenge for the practical application of potassium permanganate absorbents, but it can be overcome using the already existing innovative air filtration equipment.
I believe using something like bentonite or straight dry clay would work too. Apple season is approaching in the Southern hemisphere and my trees are full at the moment. If I can protect them from codling moth and fruit fly, I want to store them a little longer this time.
I will be preparing trays of clay, soaked in PP under my apple trays.
Hmmm, had not heard that the ethylene gas apples give off effects their ripening, just the ripening of other vegies and fruit around them.
In either case, a low tech way of dealing with the ethylene gas in root cellars has historically been to put the crates of apples up high near to the exhaust vent of the cellar. That way the gas is drawn off and out of the cellar with the normal convection cooling flow. Probably not an ideal or perfect solution but it has worked for many years.
Perhaps a combination of this along with absorption for what gas gets left behind would be a more complete solution.