RF33, The platinum acts as a catalyst to help ensure complete combustion like in a catalytic converter on a car or one of those little propane (or natural gas) catalytic heaters that are "SAFE" to use in an occupied interior space. What if your burner were 95% efficient instead of 100% and released minute portions of CO and unburned hydrocarbons? Would this prevent mosquito attracting? I don't think so! Your fuel costs for the same plume would go up about 5%. It would take a real long time to make even a hundred $ on the small fuel savings.
Since a lot of "vintage" RVs have small catalytic heaters that might be had on the used market and there are small catalytic type propane fired "tent" or similar heaters available pretty reasonable, you should be able to make her a deal. Look at the coverage on the COTS units, wouldn't you realy need more than one to do a real good job and protect everyone from the Nile Virus etc? You could split the savings you get not buying commercial. You could make a start at some small piece of platinum jewelry AND something in the way of a man toy with the savings, especially if your analysis indicated it took 2, 3, or more units to give effective coverage to your area of concern.
Patrick (teetering on the fine line between reality and tongue in cheek)